Bosch Appliances Freezer 250 SXO LP User Manual

MODEL 250SXO - OUTDOOR MODEL  
For exterior use only  
Electronic Ignition and built in Freeze protection  
Suitable for heating potable water only  
Not approved for space heating purposes  
250 SXO NG - Natural Gas  
250 SXO LP - Liquefied Petroleum (LP) Gas  
Warning: If the information in this manual is not  
followed exactly, a fire or explosion may result  
causing property damage, personal injury or death.  
Do not store or use gasoline or other flammable  
vapor and liquids in the vicinity of this or any other  
appliance.  
What to do if you smell gas  
Close gas valve.  
Do not try to light any appliance.  
Do not touch any electrical switch; do not use any  
phone in your building.  
If you cannot reach your gas supplier, call the fire  
department.  
Improper installation, adjustment, alteration,  
service or maintenance can cause injury or  
property damage. Refer to this manual. For  
assistance or additional information consult a  
qualified installer, service agency or the gas  
supplier.  
Immediately call your gas supplier from a neighbor’s  
phone. Follow the gas supplier’s instructions  
Installation and service must be performed by a  
qualified installer, service agency or the gas supplier.  
In the Commonwealth of Massachusetts this  
product must be installed by a licensed plumber or  
gas fitter.  
Upon completion of the installation, these  
instructions should be handed to the user of the  
appliance for future reference.  
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Warning  
What to do if you smell gas  
Close gas valve.  
Do not try to light any appliance.  
Do not touch any electrical switch; do not use any  
phone in your building.  
Immediately call your gas supplier from a neighbor’s  
phone. Follow the gas supplier’s instructions.  
If you cannot reach your gas supplier, call the fire  
department.  
Installation and service must be performed by a  
qualified installer, service agency or the gas supplier.  
Warning: The heater must be  
disconnected from the gas supply  
piping system during any pressure  
testing of that system at test pressures  
equal to or more than 0.5 psig.  
FCC:  
This device complies with Part 15 of the FCC rules.  
Operation is subject to the following two conditions: (1)  
This device may not cause harmful interference, and (2)  
this device must accept any interference received,  
including interference that may cause undesired  
operation.  
Fig. 1  
Caution:  
Any  
changes  
or  
modifications not expressly approved  
by the party responsible for compliance  
could void the user’s authority to  
operate the equipment.  
Fig. 2  
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2
Appliance details  
Maximum input  
2.1 Features  
175,000 Btu/h (51.2 kW)  
Parts  
Efficiency in %  
Touch Pad interface control  
Recovery efficiency 86.5%  
High power pre-mix compact burner with low NOx  
emissions  
Min. Output  
Modulating Gas Valve with constant gas: air ratio  
control  
31,131 Btu/h (9,1 kW)  
Temperature Control  
Modulating water valve for improved comfort and  
temperature control  
Selection range: 100°F (38°C) - 140°F (60°C)  
Default temperature: 122°F (50°C)  
Stability: +/- 2°F (+/- 1°C)  
Freeze protection.  
Safety  
Flame sensor (ionization) rod  
Overheat sensor  
Gas Requirement  
Gas connection (inches) - ¾”  
Inlet gas pressure under maximum operation*  
Propane: 11” - 14” water column  
Natural Gas: 5” - 14” water column.  
Temperature limiter  
Fan speed monitoring.  
High Quality Materials for Long Working Life  
Copper heat exchanger  
* To measure Gas Pressure, see Measuring Gas  
Pressure, chapter 2.9.  
High efficiency Ceramat Burner  
Water  
Compact space saver: mounts on a wall with a  
supplied bracket.  
Hot water connection (inches) - ¾”  
Cold water connection (inches) - ¾”  
Easily removable two-piece cover.  
Features  
Water valve material: Polymer (PPS) (Polypropylene  
Sulfid)  
Electronic Ignition  
Minimum water flow: 0.8 gallon/minute (3 l/m)  
LCD Display  
Minimum recommended water pressure: 30 PSI  
(2.07 bar)  
On/Off and Temperature control switches  
Reset button  
Connections:  
– Bottom of heater  
Program Key (Selectable temperature default)  
Failure codes for easy diagnostic and repair.  
Accessories  
Optional wireless remote control accessory to  
operate with the appliance.  
BOSCH is constantly improving its  
products, therefore specifications are  
subject to change without prior notice.  
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2.2 250 SXO Specifications (Technical  
data)  
Approved in US/Canada  
Capacity  
Maximum flow rate: 6.35 GPM (24 l/min) at a 45°F  
(25°C) rise.  
Maximum output  
142,968 Btu/h (41.8 kW)  
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Combustion  
NOx 55 ppm  
CO 250 ppm.  
UNPACKING THE 250 SXO HEATER  
This heater is packed securely.  
The box includes:  
Control panel shield  
Dimensions  
Pressure relief valve  
Depth (in): 8 ½” (220 mm)  
Width (in): 15 ¾” (400 mm)  
Height (in): 26” (650 mm)  
Weight: 47 pounds (21 kg).  
Bracket for wall hanging the heater  
Plastic decal shields for covering front cover screws  
and control panel, installer should affix these decals  
to the front of the unit after installation is complete.  
See Fig. 6  
Gas types  
Installation manual  
Natural Gas.  
LP Gas.  
Product registration card.  
CO2 analyzer is required to convert from one gas type  
to another. Please contact CEC for specific  
instructions.  
Do not lose this manual. Please complete and return  
the enclosed product registration card.  
Before installing the unit, be certain you have the  
correct heater for your type of Gas - Propane or  
Natural Gas. Identification labels are found on the  
shipping box, and on the rating plate which is located on  
the right side panel of the cover.  
Voltage  
120 V AC (50/60 Hz)  
Amperage  
IDLE - 40 mA  
Operation - 2,5 A  
Noise  
50 db (A)  
The 250SXO is not approved or designed for:  
Manufactured (mobile) homes, RV's or boats  
Safety devices  
Flame failure device (ionization flame rod sensor)  
Pressure relief valve (supplied with heater)  
Over heat prevention (temperature limiter).  
Heating or other recirculating/pumping applications*  
Solar/preheat backup or high temperature booster  
use  
* This includes domestic hot water circulator pump loop  
systems that may previously exist in a home hot water  
system. The use of a small electric mini-tank (4-6 gallon  
size) should be used for this application; when  
designed so the pump will circulate the hot water in the  
mini-tank only and through the building's hot water  
return loop (timed or thermostatic controlled operation  
of the pump is commonly done). The 250SXO should  
be plumbed in line before the mini-tank water heater,  
contact CEC if further instruction is needed.  
Water resistant  
IP X5 (protection against water drops).  
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2.3 Dimensions and Minimum installation clearances  
Fig. 3 Dimensions  
1
2
3
4
5
6
Cover  
On/Off switch  
Reset button  
LCD display  
Program button  
Temperature buttons  
Fig. 4 Minimum clearances  
Model 250 SXO  
3 ft.  
TOP (A)  
FRONT (B)  
BACK  
4 ft.  
0”  
SIDES  
4 ft.  
BOTTOM (C)  
1 ft.  
Table 1 Minimum clearances  
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2.4 General rules to follow for safe  
operation  
WARNING: Proper insulation of the  
water lines below the heater is required  
if below freezing temperatures, below  
32°F, are ever anticipated!  
B 1. You should follow these instructions when you  
install your heater. In the United States: The  
installation must conform with local codes or, in the  
absence of local codes, the National Fuel Gas Code  
ANSI Z223.1/NFPA 54.  
Danger: If the temperature drops  
below 5°F, freeze damage to the water  
heater itself must be prevented by  
turning off the power to the heater, then  
disconnecting the plumbing conne-  
ctions and introducing short bursts of  
compressed air (20-40 psi) through the  
heater's connections. This will remove  
the residual water in the horizontal  
pipes and water valve..  
In Canada: The Installation should conform with  
CGA B149.(1,2) INSTALLATION CODES and /or  
local installation codes.  
B 2. Carefully plan where you install the heater. Proper  
clearances must be followed.  
B 3. The appliance must be isolated from the gas  
supply piping system by closing its individual manual  
gas shutoff valve (not supplied with heater) during  
any pressure testing at pressures in excess of ½ Psig  
(3.5 kPa).  
Danger: Keep children away as the top  
of the water heater vent cap will get very  
hot during operation. Install in a place  
that prevents the top of the heater being  
reached by small children.  
The appliance and its gas connection must be leak  
tested before placing the appliance in operation.  
B 4. Keep water heater area clear and free from  
combustibles and flammable liquids. Do not locate  
the heater over any material which might burn.  
B 5. Correct gas pressure is critical for the optimum  
operation of this heater. Gas piping must be sized to  
provide the required pressure at the maximum output  
of the heater, while all the other gas appliances are in  
operation. Check with your local gas supplier, and  
see the section on connecting the gas supply.  
Danger: Flue gases will be released  
through the vent cap. Flue gas is very  
hot and contains carbon monoxide. The  
heater cannot be installed indoors. To  
prevent risk of fire and poisoning by  
carbon monoxide, assure all clearances  
indicated in manual.  
B 6. Should overheating occur or the gas supply fail to  
shut off, turn off the gas supply at the manual gas  
shut off valve, on the gas line. Note: manual gas  
shutoff valve is not supplied with the heater.  
Danger: Surface temperature around  
vent cap is less than 140°F, except  
highest top surface of vent cap may  
reach 400°F.  
B 7. Do not use this appliance if any part has been  
underwater. Immediately call a qualified service  
technician to inspect the appliance and to replace  
any part of the control system and any gas control  
which has been underwater.  
Danger: Do not place or store any  
combustible material within 5 feet of the  
appliance. Risk of fire could be caused  
by hot flue gas. Note: Exception is  
made for the wall where the appliance  
is installed and any adjacent walls or  
overhang. In this case observe  
clearances required in chapter 2.6.  
2.5 Proper location for installing your  
heater  
Carefully select the location of the water heater.  
Follow the guidelines below:  
B 1. Locate the heater where venting, gas and  
plumbing connections are feasible and convenient.  
B 2. The hot water lines should be kept short to save  
energy. Centrally locating the water heater is best. It  
is always best to have the water lines insulated to  
prevent the possibility of any freeze damage.  
Warning:  
Flammable  
materials,  
gasoline, pressurized containers, or any  
other items or articles that are potential  
fire hazards must NOT be placed on or  
adjacent to the heater. The appliance  
area must be kept free of all  
combustible materials, gasoline and  
other flammable vapors and liquids.  
B 3. The water in this heater is cold and always remains  
cold except for the times that hot water is being used.  
The heater is equipped with freeze prevention  
equipment that will operate and prevent freezing of  
the water in the heater to 5°F with no wind chill.  
Electrical power must be maintained to the heater to  
allow this to function.  
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2.6 Heater Placement and Clearances  
2.7 Mounting installation  
The 250 SXO is design certified for installation directly  
on a combustible wall. (see 2.7 Mounting installation)  
For installation on vinyl siding see Fig. 10. Keep the area  
below the heater free of combustible material.  
Warning: before starting installation:  
B check that there are no loose parts  
inside the appliance  
B ensure that gas pipe, gas valve, mixer,  
fan and burner have no damage and are  
properly fitted.  
Minimum clearances  
If the appliance is installed under an overhang, there  
must be a 36” clearance from the top of the appliance  
and the mounting area must be open in front and on the  
sides of the appliance.  
Front cover should be removed in order to  
inspect components visually (see  
instructions below).  
i
To remove front cover.  
B Loosen the two Philips head screws located on front  
panel (beneath plastic decal shields if they are  
already attached, see Fig. 6).  
Plastic decals  
Fig. 5  
Danger: The top of the kit will get hot  
due to the flue gases. Install away from  
children.  
Min.  
distances  
Ref. Description  
A
B
C
Directly below or from an  
opening; operable windows,  
doors and any fresh air  
openings  
4 ft  
4 ft  
Fig. 6 Remove front cover  
B Remove the two top screws securing the vent cap to  
the top of the heater, being careful the washers on  
the screws are not lost, see Fig. 7.  
From any adjacent wall or tall  
shruberry  
D
Below a gutter, sanitary  
pipework, eaves or overhang  
E
F
3 ft  
1 ft  
Above ground  
From a gas meter, gas  
regulator, electrical box or  
another 250SXO heater  
G
3 ft  
Table 2 Clearances  
Fig. 7  
B Lift the top vent cap completely upward from the  
heater.  
B From the bottom of the heater, holding the sides, lift  
the front cover panel of the heater upward and  
slightly toward you to remove.  
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B After inspection, replace front cover and tighten  
screws, then replace plastic decal shields.  
B Fix the top vent cap on the top of the heater, as  
shown in Fig. 8). Make sure the vent cap is well fitted  
by taking special care that the front cover stays inside  
the extended corners of the vent cap, as shown in  
Fig. 8). The sides of the cover must be pressed with  
your hands to ensure it fits inside those corners.  
Secure it in place with its two screws.  
Fig. 9  
Warning: Do not mount heater directly  
to vinyl siding. With vinyl siding  
surfacing, a 6' x 4' area of the siding  
must first be removed and then  
replaced with wood or other non-plastic  
made material. See Fig. 10.  
Fig. 8  
B The water heater is design certified for mounting on  
a wall. Secure the wall mounting bracket provided  
with the water heater to a wall surface. See Fig. 9.  
B The installation method of the mounting bracket will  
depend on what type of surface it’s being mounted  
to. Due to the varying types of building surfaces, the  
installer must decide on how best to support and  
level the heater on an outside wall. It is always  
recommended that horizontal or vertical support  
boards or plywood sheathing (1/2” minimum) first be  
attached to the wall surface. The heater must also be  
kept level on the wall surface.  
Fig. 10  
Vent Safety System  
The 250 SXO will shut down if the intake or exhaust  
louvers on the vent cap are blocked for any reason; see  
troubleshooting section on page 19. See error code  
table to confirm error, correct the problem and then  
reset the heater before operating.  
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2.8 Gas piping & connections  
Warning: The heater must be isolated  
from the gas supply piping system  
during any pressure testing of that  
system at test pressures equal to or  
more than 0.5 psig.  
Before connecting the gas supply, check the rating  
plate on the right side of the heater to be sure that the  
heater is rated for the same gas to which it will be  
connected.  
In the United States: The installation must conform with  
local codes or, in the absence of local codes, the  
National Fuel Gas Code ANSI Z223.1/NFPA 54.  
In Canada: The Installation should conform with CGA  
B149 INSTALLATION CODES and/or local installation  
codes.  
The water heater must not be piped with gas supply  
pressures in excess of 0.5 psig. If overpressure has  
occurred, such as through improper testing of the gas  
lines or malfunction of the supply system, the gas valve  
must be checked for safe operation.  
When connections are made, check for gas leaks at all  
joints. Apply some gas leak detection solution to all gas  
fittings. Bubbles are a sign of a leak. A Combustible  
Gas Detector may also be used to detect for leaks.  
GAS LINE SIZING  
The gas supply piping should be sized according to the  
applicable plumbing code for a maximum draw of  
175,000 BTUH. Measure the length of gas supply line  
and use the tables in Fig. 12 or the gas line  
manufactures sizing tables to determine the pipe  
diameter necessary to accommodate the BTU demand  
of the unit. If there are more gas drawing appliances on  
the line, size the gas line according to the total maximum  
amount of BTU draw for all appliances.  
Danger: If you have a leak, shut off the  
gas. Tighten appropriate fittings to stop  
leak. Turn the gas on and check again  
with a gas leak detection solution.  
Never test for gas leaks using a match  
or flame.  
Note: Under sizing the gas line may result in diminished  
output and improper operation. See chapter 2.9 for the  
procedure to confirm gas pressure.  
Inlet gas particle screen  
Gas piping  
Fig. 11  
B Install a manual gas shut off valve, on the gas supply  
line.  
B The use of a union when connecting gas pipe to the  
gas inlet connection is important, this will facilitate  
any necessary servicing and cleaning of the inlet gas  
particle screen.  
B The minimum diameter required for any appliance  
connector used is ¾”.  
B National Fuel Gas Code requires that a sediment  
trap (drip leg) be installed on gas appliances not so  
equipped. The drip leg must be accessible and not  
subject to freezing conditions. Install in accordance  
with the recommendations of the serving gas  
supplier.  
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FOR NATURAL GAS  
Maximum Capacity of pipe in Cubic Feet of Gas per Hour for Gas Pressure of 0.5 Psig or less and a Pressure drop  
of 0.3 in Water Column (0.75mbar).(Based on a 0.60 Specific Gravity Gas) Btu numbers given in thousands.  
Follow boxed numbers for piping just one 250 SXO (example: ¾” B.I. Natural Gas pipe for 20 ft (6.1m). will  
handle 190,000 btu’s (55.7 kWh). For multiple appliances combine the total btu input load and then refer to  
applicable chart below.  
Nominal  
Iron  
Length of Black Iron Pipe, Feet  
Pipe  
Internal  
Size, Diameter  
inches inches  
10  
20  
30  
40  
50  
60  
70  
80  
90  
100  
125  
150  
175 200  
1/4  
3/8  
1/2  
0.364  
0.493  
0.622  
32  
72  
22  
49  
92  
18  
40  
73  
15  
34  
63  
14  
30  
56  
12  
27  
50  
11  
25  
46  
11  
23  
43  
10  
22  
40  
9
8
8
7
6
21  
38  
18  
34  
17  
31  
15  
28  
14  
26  
132  
3/4  
1
0.824  
1.049  
278  
520  
190  
350  
152  
285  
130  
245  
115 105  
96  
90  
84  
79  
72  
64  
59  
55  
215 195 180  
170  
160  
150  
130  
120  
110 100  
1 1/4  
1 1/2  
2
1.380  
1.610  
2.067  
1050  
1600  
3050  
730  
590  
890  
500  
760  
440 400 370  
670 610 560  
350  
530  
320  
490  
930  
305  
460  
870  
275  
410  
780  
250  
380  
710  
225 210  
350 320  
650 610  
1100  
2100 1650 1450  
1270 1150 1050 990  
Length of Flexible Corrugated Stainless Steel Tubing (CSST), Feet  
Tube  
size,  
inches  
EHD*  
10  
20  
58  
30  
47  
96  
40  
41  
50  
37  
60  
34  
1/2  
3/4  
1
18 EHD 82  
23 EHD 161  
30 EHD 330  
116  
83  
75  
68  
231 188  
456 374  
162  
325  
144  
292  
131  
267  
* EHD = Equivalent Hydraulic Diameter. The greater the  
value of EHD, the greater the gas capacity of the tubing  
.
1 1/4 37 EHD 639  
FOR LP GAS  
Maximum Capacity of Pipe in Thousands of BTU per Hour of Undiluted Petroleum Gases (at 11 inches Water Column Inlet  
Pressure) (Based on a Pressure Drop of 0.5 Inch Water Column).  
* EHD = Equivalent Hydraulic Diameter. The greater the  
value of EHD, the greater the gas capacity of the tubing.  
Length of Flexible Corrugated Stainless Steel Tubing (CSST), Feet  
Nominal  
Tube  
size  
inches  
Iron Pipe  
Size,  
Black Iron Pipe  
Length of Pipe, Feet  
EHD*  
Inches  
10 20 30  
40 50 60 70 80 90 100 125 150  
10  
20  
91  
30  
74  
40  
64  
50  
58  
60  
53  
1/2  
275 189 152 129 114 103 96 89 83  
78  
69  
63  
1/2  
3/4  
1
18 EHD 129  
3/4  
1
567 693 315 267 237 217 196 185 173 162 146 132  
107 732 590 504 448 409 378 346 322 307 275 252  
23 EHD 254 183 151  
30 EHD 521 365 297  
131  
256  
449  
118  
227  
397  
107  
207  
359  
1 1/4 220 149 121 103 913 834 771 724 677 630 567 511  
1 1/2 330 229 185 155 141 127 118 108 102 976 866 787  
1 1/4 37 EHD 971 661 528  
Maximum Capacity of Semi-Rigid copper Tubing in  
Copper  
Outside  
diameter  
Inch  
Length of Tubing, Feet  
Thousands of BTU per Hour of Undiluted Liquefied  
Petroleum Gases (at 11 inches Water Column Inlet  
10 20  
39 26  
92 62  
30 40  
21 19  
50 41  
50  
_
60 70 80 90 100  
Pressure).  
3/8  
1/2  
_
_
_
_
_
(Based on a Pressure Drop of 0.5 Inch Water Column)  
37  
79  
35 31 29 27 26  
72 67 62 59 55  
5/8 199 131 107 90  
* Source National Fuel Gas Code NFPA 54, ANSI  
Z223.1 - No Additional Allowance is necessary for an  
ordinary number of fittings  
3/4 329 216 181 145 131 121 112 104 95 90  
Fig. 12  
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2.9 Measuring gas pressure  
Static Gas Pressure Reading (see Chapter 2.9)  
enter here: ___________________  
2.9.1 Connecting Manometer  
B Shut off gas.  
Operating Gas Pressure Reading (see Chapter 2.9)  
enter here: ___________________  
B Remove front cover and locate inlet gas pressure  
measuring point (see Fig. 14).  
Table 3  
B Loosen screw inside test point fitting (do not remove)  
HIGH ALTITUDE OPERATION  
and connect manometer tube on test point.  
Altitude  
Natural  
Gas:  
Liquid  
Propane:  
2.9.2 Static Pressure Test  
B Turn gas supply back on.  
For operation at  
elevations  
above 2,000 ft  
(610 m) the  
equipment  
ratings shall be  
reduced at the  
rate of 4% for  
each 1,000 ft  
(305 m) above  
sea level  
B Operate all other gas appliances on same gas piping  
0 - 4,000 ft  
(0 - 1,219 m)  
no  
no  
modification  
modification  
system at maximum output.  
B Record static gas pressure reading in table 3.  
CO2 adjustment with flue  
cghaaspatnearl9yzeforrreinqsutirruecdtiSonese.  
2.9.3 Operating Pressure Test  
4,000 ft - 7,000 ft  
(1,219 m - 2,134 m)  
B ON/OFF switch in position OFF (0).  
B Press and hold "Program" (M) button and turn ON/  
Above 7,000 ft  
(above 2,134 m)  
OFF switch to ON position.  
Not approved  
Table 4  
Fig. 13  
B As soon as '188' is displayed, release "Program"  
button and the display should read P2.  
B Press  
, until P1 appears.  
Note: While in this mode the appliance will run  
constantly at maximum power and allow maximum water  
flow. These program modes are for test purposes only  
and not intended for normal operation.  
B Turn on high volume of hot water flow (at least 6  
gpm) and heater will ignite.  
B Record operating gas pressure reading in table 3.  
Gas pressures lower than 5" W.C. for Natural Gas or  
11" W.C. for LPG will result in insufficient degree rise  
to the hot water being used, and must be corrected.  
See Gas Connections, chapter 2.8.  
Fig. 14 Gas pressure measuring (left tapping)  
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lowest pressure range setting recommended is 30-50  
psi (2.07 and 3.45bar).  
2.10 Water connections  
When facing the heater, the ¾” cold water inlet is on the  
bottom right and the hot water outlet is on the bottom  
left. Install the heater where it’s centrally close to hot  
water use points if possible, and make hot water piping  
runs as short as possible.  
Connecting the pressure relief valve (PRV)  
A listed pressure relief valve supplied with the heater  
must be installed at the time of installation. No valve is  
to be placed between the PRV and the heater. No  
reducing coupling or other restriction may be installed  
in the discharge line. The discharge line must be a  
minimum of 4” above a drain and installed such that it  
allows complete drainage of both the PRV and the line.  
The location of the PRV must be readily accessible for  
servicing or replacement, and be mounted as close to  
the water heater as possible. See Fig. 16. To install the  
PRV, a suitable fitting connected to an extension on a  
“T” fitting can be sweated to the hot water line.  
Support all piping.  
INLETFILTER  
SCREEN  
COLD  
HOT  
Fig. 15  
B THE USE OF A UNION WHEN CONNECTING  
BOTH WATER PIPES TO THE INLET AND  
OUTLET CONNECTIONS IS RECOMMENDED,  
THIS WILL FACILITATE ANY NECESSARY  
SERVICING AND REQUIRED CLEANING OF  
THE INLET WATER PARTICLE SCREEN.  
Although water piping throughout your structure may be  
other than copper, we recommend that copper piping  
or suitably rated stainless steel flex line piping be used  
for at least three feet before and after the heater (follow  
local codes if more stringent). Never sweat any rigid  
piping directly to or beneath the water connections,  
damage can occur to the internal water valve from  
heating of the pipe. Plastics or other PEX type plumbing  
line materials are not suitable for connecting directly to  
the water heater. Keep water inlet and outlet pipes to no  
less than ¾" (19.05mm) diameter to allow the full flow  
capacity.  
Fig. 16 Plumbing Connections and Pressure Relief  
Valve  
It is recommended that all water piping below the  
heater be properly insulated to avoid heat loss. If  
below freezing temperatures are ever anticipated  
where the heater is located, insulation material  
is required and must be capable of protecting the  
piping from freezing. The freeze protection that is  
equipped within the heater will not prevent any  
freeze damage to the exterior water piping.  
If the cold and hot connections to the heater are  
reversed, the heater will not function. Be certain there  
are no loose particles or dirt in the piping. Blow out or  
flush the lines before connecting to the water heater.  
Full port valves should be installed on both the cold  
water supply and hot water outlet lines to facilitate  
servicing the heater (see Fig. 16). For installation on a  
private well system with the use of a pressure tank, the  
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Appliance details  
2.11 Electrical connections  
Warning: The heater is equipped with  
freeze prevention equipment that will  
operate and prevent freezing of the  
water in the heater to 5°F with no wind  
chill. Electrical power must be  
maintained to the heater to allow this to  
Warning: Confirm that the water  
heater is appropriately grounded and  
that the installation meets all electrical  
codes. Outdoor electrical outlets have  
special requirements.  
function.  
WARNING:  
Proper  
insulation of the water lines below  
the heater is required if below  
freezing temperatures, below 32°F,  
are ever anticipated.  
Warning:  
For  
safety  
reasons,  
disconnect the power supply to the  
heater before any service or testing is  
performed.  
2.12 Operating instructions  
Warning: This heater must be  
electrically grounded in accordance  
with the most recent edition of the  
National Electrical Code. NFPA 70. In  
Canada, all electrical wiring to the  
heater should be in accordance with  
local codes and the Canadian Electrical  
Code, CSA C22.1 Part 1. Do not rely  
on the gas or water piping to ground the  
metal parts of the heater.  
B Remove the control cover shield to access the  
controls of the water heater.  
The 250 SXO requires an electrical power supply from  
a 120VAC 60Hz circuit and must be properly  
grounded.  
A means for switching off the 120VAC power supply  
must be provided.  
The heater is wired as shown in the wiring diagram  
(chapter 6, Fig. 29).  
Fig. 18  
Warning: The control cover must be  
replaced after the initial operation  
begins, and must be in place at all  
times.  
B Before proceeding with the operation of the heater  
make sure that the system is filled with water.  
B Turn off power supply to heater.  
B Open the cold water inlet supply to the heater fully.  
B Open a hot water faucet to permit the water to fill the  
heater and the piping and to eliminate the air trapped  
in the system.  
B Close the hot water faucet after the water flows freely  
and all the air has escaped from the system. Turn on  
power supply to heater. The water heater is now  
ready to operate.  
Appliance electrical  
power supply  
Fig. 17  
NOTE: A default temperature setting of  
122 F will appear on the display screen.  
i
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Appliance details  
2.13 For your safety read before  
operating your water heater  
NOTE: on a first time initial  
installation or after gas line work  
has been done, air in the gas line  
will cause ignition delay when the  
hot water is turned on. This will  
result in an error (EA or EC) on the  
units display screen. This is  
normal. When this occurs, leave  
the hot water running and wait 3-5  
seconds, then press reset button  
to reset the unit (Fig. 19, pos. 2).  
Wait for (EA or EC) to disappear.  
The heater will begin to attempt  
ignition again, if the (EA or EC)  
reappears then repeat this same  
process until all air has been bled  
from the gas line.  
i
Warning: If you do not follow these  
instructions exactly, a fire or explosion  
may result causing property damage,  
personal injury or loss of life.  
A. This appliance is equipped with electronic ignition for  
lighting the main burners. When turning the heater on,  
follow these instructions exactly.  
B. Before operating the unit, turn the On/Off switch to  
the right position.  
WHAT TO DO IF YOU SMELL GAS  
B Do not try to light any appliance.  
B Do not touch any electric switch; do not use any  
phone in your building.  
When the heater is in operation you will hear its power  
vent fan and burner operating. Upon turning off the hot  
water flow the power vent fan will continue to operate  
for up to 60 seconds to exhaust all flue gases. The  
power vents fan speed is variable depending on the rate  
of hot water used and the burner output.  
B Immediately call your gas supplier from a neighbors  
phone. Follow the gas supplier’s instructions.  
B If you cannot reach your gas supplier, call the fire  
department.  
C. Use only your hand to turn the on/off control switch.  
Never use tools. Follow these instructions exactly. If  
control switch is jammed, close the gas supply and call  
a qualified service technician. Attempted forceful repair  
may result in a fire or explosion.  
D. Do not use this appliance if any part has been under  
water. Immediately call a qualified service technician to  
inspect the appliance and to replace any part of the  
control system and any gas control which has been  
under water.  
TO TURN OFF GAS TO APPLIANCE  
B Turn off the manual gas shut off valve on the supply  
line to the heater and set the ON/OFF switch to the  
OFF position (turn to the left position). Note: a  
manual gas shut off valve is not supplied with the  
heater.  
2.14 Lighting and operating instructions  
B 1. STOP! Read the previous safety information.  
B 2. The gas valve must be shut off by putting the ON/  
OFF switch to the OFF position (turn to the left  
position). Wait five (5) minutes to clear out any gas.  
If you smell gas, STOP! Follow “B” in the safety  
information above. If you do not smell gas, go to the  
next step.  
B 3. This appliance is equipped with electronic ignition  
for lighting the main burners. When turning the  
heater on, follow these instructions exactly.  
B 4. Set the ON/OFF switch to the ON position (turn to  
the right position).  
B 5. Open a hot water tap.  
B 6. The burners will remain on until the hot water tap  
is turned off.  
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Operation instructions  
3
Operation instructions  
Fig. 19  
1
2
3
4
5
6
On/Off switch  
Reset button  
Program button  
Increasing temperature button  
Decreasing temperature button  
LCD display  
B Press buttons  
and  
in order to reach  
requested temperature.  
3.1 Power  
On  
B To start the appliance switch the button to the ON  
position (turn to the right position).  
LCD display the default temperature - temperature  
factory setting 122°F (50°C).  
Fig. 21  
If the outlet water temperature is set too high, the heater  
can produce temperatures that are too hot. A  
temperature balance shower valve can automatically  
mix in cold water to reduce such hot water temperature.  
In the event of any temperature instability with the use  
of a temperature balance shower valve, refer to shower  
valve manufacturer's instructions for internal adjustment  
setting. Adjustments should be made to the hottest  
setting in the shower valve. Additionally the temperature  
control of the heater can be lowered to produce a more  
comfortable hot water temperature.  
Fig. 20  
Off  
B To shut down the appliance, switch the button to the  
OFF position (turn to the left position).  
3.2 Temperature selection  
To select water temperature outlet:  
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Operation instructions  
Setting the water temperature  
The desired temperature of the hot water can be adjusted on the front control panel of the heater.  
The 250 SXO has an electronically controlled gas valve that modulates the burner input in response to both varying  
hot water flow rates and/or changes in any incoming and outgoing water temperatures.  
Hot Water Flow and Temperature with Various Inlet Temperature (gpm/Fahrenheit)  
7.00  
6.00  
5.00  
4.00  
3.00  
2.00  
1.00  
0.00  
90  
100  
110  
120  
130  
140  
150  
Hot water temperature (ºF)  
Inlet (ºF) 40  
Inlet (ºF) 50  
Inlet (ºF) 60  
Inlet (ºF) 70  
Hot Water Flow and Temperature with Various Inlet Temperature (lpm/Celsius)  
24.00  
20.00  
16.00  
12.00  
8.00  
4.00  
0.00  
35  
40  
45  
50  
55  
60  
65  
Hot water temperature (ºC)  
Inlet (ºC) 4  
Inlet (ºC) 10  
Inlet (ºC) 16  
Inlet (ºC) 21  
Fig. 22 Flow/temperature charts  
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Operation instructions  
3.3 Use of remote control accessory  
Fig. 26 Reset button  
If the problem persists, contact your installer.  
3.6 Program button  
Fig. 23 Remote control  
Program button can be used/programmed in the  
appliance and in the remote control.  
The wireless remote control accessory and the  
temperature selector buttons on the front of the water  
heater operate identically. Contact your distributor or  
CEC to order if the remote control accessory is  
preferred. Modification of the water heaters interior  
control unit (Fig. 32, component 12) is required when  
programming the remote control with this heater.  
Programming “Program” function  
Programming actions are similar for both controls  
(appliance control pad and wireless remote control).  
NOTE: up to 6 remote controls can be  
programmed for one single water heater,  
each with a range distance of 98 ft (30 m).  
i
3.4 Operation  
B When a hot water tap is opened, main burner ignites  
Fig. 27 “Program” key  
and LCD displays indication  
.
B Press buttons  
and  
to select temperature to  
be memorized.  
B Hold “Program” button for 3 seconds to save  
temperature.  
When LCD stops blinking. Temperature is saved on  
“Program”.  
Fig. 24  
Using “Program” function  
In order to select memorized temperature  
B LCD blinks until selected temperature is reached.  
B Press “Program” key.  
3.5 Reset button  
LCD shows pre-memorized temperature, which is now  
the hot water selected temperature.  
If the LCD shows the error symbol  
Note: do not use the ON/OFF switch when error is  
present.  
See the error code on LCD and consult  
Troubleshooting” section.  
.
3.7 Locked condition  
This condition is only valid for appliances with more than  
1 controller (an appliance with one or more remote  
controls).  
Fig. 25  
Fig. 28 Locked condition  
After  
following  
instructions  
indicated  
in  
Whenever LCD shows  
the temperature setting  
Troubleshooting” section  
cannot be adjusted because the appliance is in use by  
a user which already selected a different temperature.  
Appliance will be automatically unlocked after closing  
hot water tap.  
B press reset button in order to make the appliance  
ready-to-work.  
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Maintenance and service  
4
Maintenance and service  
BURNERS DO NOT IGNITE WHEN HOT WATER IS  
TURNED ON  
Warning: Always turn off the electrical  
power supply, turn off the manual gas  
valve and turn off the manual water  
control valves whenever servicing.  
Cold incoming water connection made to  
wrong side of heater  
Make sure cold water inlet connection is plumbed to  
the right side of heater when facing unit  
The unit should be checked once a year by a gas  
technician. If repairs are needed, the repairs should be  
done by a gas technician  
Water flow rate at hot water tap is too low  
A minimum of 0.8 gallon/minute (3 l/m) is required to  
activate the heater  
To remove front cover  
Cold water inlet filter screen is dirty  
Remove water inlet filter screen and clean. The  
screen is located at the inlet connection to the water  
heater, disconnecting the main cold supply line at the  
heater is required. Check and clean faucet aerator  
screens too.  
B See instructions to remove front cover on page 8.  
Systems and parts that should be checked at  
least once a year  
Reference diagrams on pages 24 and 25.  
Venting system  
Crossover in plumbing  
Burners -see page 24 for observation window  
The heater activates when there is sufficient water  
flow through its water valve, a minimum of 0.8 gallon/  
minute (3 l/m) is required. If there is a crossover in the  
plumbing, the necessary hot water flow rate through  
the unit may not be reached, even though the flow at  
the hot water tap is sufficient. A plumbing crossover  
can be caused by a failed washer at a single lever  
faucet, incorrect plumbing or a faulty mixing valve in  
the piping. The crossover will create a back pressure  
on the water heater and prevent an adequate flow of  
water through it. To confirm there is no crossover in  
the plumbing, shut off the cold water supply feed to  
the water heater. Individually open each of the hot  
water taps. There should be no water flowing under  
a constant pressure. If there is a constant flow of  
water then the plumbing crossover must be  
corrected before the heater can operate properly.  
See relief valve manufacture's instruction for  
pressure relief valve maintenance  
Periodic cleaning of the water filter screen, see Fig.  
15, chapter 2.10.  
Flushing the heat exchanger with a descaling  
solution if mineral build up is evident. Scale build up  
will shorten the life of the water heater, descale heat  
exchanger thoroughly and repeat annually depending  
on mineral content of ground water.  
5
Troubleshooting  
Introduction  
The 250 SXO burner is activated by a water flow valve.  
Numerous water related problems can cause this water  
valve to malfunction such as: Insufficient water flow  
volume to activate the burners at its minimum flow  
requirement; Dirt in the inlet filter screen; Sediment  
build-up in faucet aerators, or shower heads; Uneven  
pressures between cold and hot (with single lever mix  
valves); and Plumbing crossovers. These water flow  
related problems can cause the heater to deliver less  
than its full output, or to fail to ignite or to shut down  
completely.  
Problems stated below in upper case and in bold face  
should be investigated when there is a problem with the  
performance of the water heater but there is NO error  
code on the heater's LCD display or wireless remote  
control.  
WATER IS TOO HOT  
Temperature selection too high  
Lower temperature adjustment on heater or wireless  
remote control accessory, see chapter 3.2.  
WATER IS NOT HOT ENOUGH  
Temperature selection too low  
Increase temperature adjustment on heater or  
wireless remote control accessory, see chapter 3.2  
Btu input is too low due to inadequate gas line  
sizing  
See specifications in chapter 2.8 - 2.9. The 250  
SXO requires adequate gas pressure to reach  
desired temperatures, to compensate for inadequate  
gas supply or lack of gas pressure the 250 SXO will  
effectively reach the selected output temperature by  
reducing the hot water flow rate. Its motorized water  
valve makes this adjustment  
Any failures that result in a displayed error code are  
referenced on page 21. A Functional Scheme of the  
250 SXO is detailed on page 23. If there is a problem  
with the installation, venting or operation of the unit, the  
heater will communicate the source by these error  
codes.  
Cold water is mixing with the hot water outlet  
(crossover)  
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Troubleshooting  
Test by following 4th bullet under BURNERS DO  
NOT IGNITE WHEN HOT WATER IS TURNED ON.  
control of the heater can be lowered to produce a  
more comfortable hot water temperature.  
Inlet water pressure is erratic due to  
fluctuating supply water pressure  
LOW WATER FLOW/PRESSURE  
Too many hot water applications are being  
used simultaneously or too much flow is being  
demanded  
The 250 SXO will effectively support two 2.0-2.5  
gpm shower heads simultaneously or multiple sink  
applications. Greater draws will result in increased  
pressure drop and reduced flow at taps. See flow/  
temperature chart on page 17.  
For installation on a private well system with the use  
of a pressure tank, the lowest pressure range setting  
recommended is 30-50 psi (2.07-3.45 bar). The use  
of a pressure reducing valve after the pressure tank  
is also an effective way to maintain a constant water  
pressure to the water heater. Watts brand 25AUB-  
¾” or N35B-¾” pressure relief valves or equivalent  
are suggested.  
Btu input is too low due to inadequate gas line  
sizing  
See specifications in chapter 2.8 - 2.9. The 250  
SXO requires adequate gas pressure to reach  
expected temperatures and flow rates, to  
compensate for inadequate gas supply or lack of gas  
pressure the 250 SXO will effectively reach the  
selected output temperature, but only by reducing  
the hot water flow rate. Its motorized water valve  
makes this adjustment. Proper gas pressure will  
need to be delivered before the motorized water  
valve will allow greater flow rates through it. Lowering  
the set temperature will also allow increased water  
flow rate through the motorized water valve. See  
flow/temperature chart on page 17.  
Cold water inlet filter screen is dirty  
Remove water inlet filter screen and clean. The  
screen is located at the inlet connection to the water  
heater, disconnecting the main cold supply line at the  
heater is required. Check and clean faucet aerator  
screens too.  
HOT WATER TEMPERATURE FLUCTUATES /  
UNIT DEACTIVATED  
Unbalanced pressure in water lines  
Any restriction caused by the water heater in the hot  
water system can result in uneven pressures  
between the cold and the hot. In such cases when  
mixing cold water at the tap (manually or  
automatically through a mix-type shower valve) the  
lower hot water pressure may be overpowered by the  
higher cold water pressure in the building and cause  
the hot water flow rate to fall below the minimum rate  
required. A pressure balance valve will help to  
resolve this symptom.  
Temperature balance valves  
If the outlet water temperature is set too high, the  
heater can produce temperatures that are too hot. A  
temperature balance shower valve can automatically  
mix in cold water to reduce such hot water  
temperature. In the event of any temperature  
instability with the use of a temperature balance  
shower valve, refer to shower valve manufacturer's  
instructions for internal adjustment setting.  
Adjustments should be made to the hottest setting in  
the shower valve. Additionally the temperature  
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Troubleshooting  
Display Cause  
Solution  
E9  
EA  
Temperature limiter opened circuit (overheat).  
Trips at 220F (104C).  
Check connections. *  
Check heat exchanger condition.*  
No ionization during safety time (safety time out).  
Note: appliance makes 3 ignition attempts  
before entering error mode “EA”.  
Check gas pressure. (see chapter 2.9  
)
*
Check that gas is not diluted with air, as a  
result from recent gas pipeline rework.*.  
Check if vent terminal is blocked (especially  
when the appliance starts up for some sec-  
onds and then looses ionization signal).*  
Check ionization electrode.*  
EC  
FA  
The ionization signal momentarily disappeared  
more then 5 times in less then 30 seconds. CO2  
may be out of adjustment  
Check for a proper ground.*  
Check CO2 levels.* (see chapter 9)  
Leakage error (gas valves do not close gas  
circuit).  
Check gas valve and control unit.*  
F7  
E0  
Ionization error (flame sensing at stand-by).  
Internal software/hardware failure.  
Check control unit.*  
Check control unit.*  
A7  
Hot water temperature sensor/receiver defect  
(from control unit).  
Check water temperature sensor/receiver and  
connections.*  
Check incoming water temperature to heater, it  
must be above 32°F (0°C)  
A9  
Hot water temperature sensor/receiver mis-  
Check that the water temperature sensor/receiver is  
properly assembled on the horizontal of the hot  
water pipe.*  
(flashing) assembled (from control unit).  
Note: if display shows “A9” flashing, the  
appliance can be operated normally, but  
performance may be affected.  
Check that the water temperature sensor/receiver is  
free from corrosion or moisture.*  
C1  
FAN rotation too low at start-up (from control  
unit).  
Check supply voltage.*  
Check fan and connections.*  
Check control unit.*  
Check if vent terminal is blocked.*  
C6  
C7  
FAN rotation too low at operation (from control  
unit).  
Check supply voltage.*  
Check fan and connections.*  
Check control unit.*  
No rotational speed sensor signal from FAN  
Check fan and connections.*  
Check control unit.*  
CA  
E2  
Water flow signal over specified maximum value Check water valve and flow sensor.*  
Inlet temperature sensor fault  
Check water temperature sensor/receiver and  
connections.*  
Check incoming water temperature to heater, it  
must be above 32°F (0°C)  
A2  
Overheat protection fault  
Check connections to the overheat protection.*  
Check sensor continuity.*  
Check heat exchanger sealings and walls.*  
Table 5  
* By installer or service technician only.  
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Electrical diagram  
6
Electrical diagram  
Fig. 29 Electrical scheme  
1
2
3
4
5
6
Intlet water temperature sensor  
Ionization sensor  
Water flow sensor  
Over heat protection  
Temperature limiter  
Gas valve  
7
Fan  
8
Water valve  
9
AC Plug  
10  
11  
12  
13  
14  
15  
16  
17  
18  
19  
20  
Ignition electrode  
Display PCB  
ON/OFF switch  
Fuse T 2,5A  
Fuse T 3,15A  
Terminal block  
Ground post  
Outlet water temperature sensor  
Connector for Anti-freeze  
Anti-freeze device (Heating resistors)  
Temperature sensor  
Fig. 30 Anti-freeze electrical scheme  
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250 SXO Functional scheme  
7
250 SXO Functional scheme  
Fig. 31 Functional scheme  
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Interior components diagram and parts list  
8
Interior components diagram and parts list  
8.1 Interior components  
Fig. 32 Components  
1
Cover  
2
3
4
5
6
7
8
On/Off switch  
Reset button  
LCD display  
Program button  
Temperature buttons  
Flue gas collector  
Mixer  
9
Heat exchanger  
Observation window  
Inlet air duct  
Control unit  
Exhaust fan  
Water valve  
10  
11  
12  
13  
14  
15  
Gas valve  
Fig. 33 Appliance overview  
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Interior components diagram and parts list  
8.2 Components diagram  
Fig. 34 Components Diagram  
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Interior components diagram and parts list  
8.3 Parts list  
Item  
Description  
Front cover  
Reference  
1
2
8 705 421 915  
8 705 506 753  
8 705 406 285  
8 704 701 052  
8 716 102 607  
8 704 701 054  
8 700 205 147  
8 700 400 015  
8 710 103 045  
8 714 606 002  
8 705 700 097  
8 700 507 001  
8 700 205 134  
8 708 505 016  
8 708 120 515  
8 704 701 050  
8 708 107 020  
8 707 204 039  
8 705 700 115  
8 704 701 059  
8 704 701 062  
8 707 021 019  
8 700 103 014  
8 707 207 153  
8 707 207 133  
8 704 401 220  
8 704 401 214  
8 704 401 239  
8 704 401 268  
8 700 400 019  
7 709 003 243  
8 700 400 022  
8 705 700 100  
8 705 700 114  
8 700 715 156  
8 700 715 155  
8 700 507 069  
8 700 715 247  
8 707 206 204  
Shield  
3
Heat exchanger  
Heat exchanger top gasket  
Clip  
4
5
6
Heat exchanger bottom gasket  
O-ring  
7
8
Temperature sensor  
Washer 1/2"  
9
10  
11  
12  
13  
14  
15  
16  
17  
18  
19  
20  
21  
22  
23  
24  
25  
26  
27  
28  
29  
30  
31  
32  
33  
34  
35  
36  
37  
38  
39  
Table 6  
Wireform spring  
Air inlet duct  
Water filter  
O-ring  
Water valve with engine  
Main burner  
Fan / Burner gasket  
Set of electrodes  
Exhaust Fan  
Gas / Air Mixer  
Mixer / Fan gasket  
Gas valve washer  
Gas valve  
Gas valve washer  
Remote control  
Control unit  
Ignition cable  
Cables / 24V  
Cables  
Power supply cord  
Overheat cutoff fuse  
Top vent cap  
Freeze protection device  
Flue gas collector  
Flue gas collector collar  
Cold water pipe  
Hot water pipe  
Air inlet screen  
Crossover tube  
Overheat sensor (ECO)  
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Special adjustment for measuring and adjusting CO2 levels  
9
Special adjustment for measuring and adjusting CO levels  
2
The CO2 can only be adjusted by a certified gas  
technician with a calibrated CO2 analyzer.  
B. Measuring CO2 (Cover Installed):  
B Open hot water taps to achieve a flow rate of at least  
4 gallons per minute. (1 tub and 2 sinks should be  
sufficient).  
Caution: One factor that may affect  
CO2 levels is improper gas pressure.  
Please see Chapter 2.9 for the  
procedure to measure gas pressure  
and record your findings below:  
B Record the CO2 reading in P2 below. (Analyzer  
reading may take several minutes to stabilize).  
B Press the  
button until P1 appears. Unit will ramp  
up to high fire and the flow should increase.  
Static Gas Pressure:  
“ WC  
“ WC  
B Record the CO2 reading in P1 on the next page.  
P2 CO2 Reading:  
% CO2  
P1 Operating Pressure:  
P1 CO2 Reading:  
% CO2  
The P1 minimum operating pressure is 5" WC for  
Natural Gas and 11"WC for Propane. Do not proceed  
in adjusting CO2 until pressure has been verified to be  
at or above these levels, but not to exceed 14” WC.  
Compare your readings to those found in table 1 under  
the “With Front Cover” column. If CO2 readings are off  
make adjustments as outlined below.  
A. Once Pressure is good  
Note: The “Without Front Cover” column gives  
approximate values with the cover off to ease the  
adjustment process. Final readings should be taken  
with the cover on.  
B Turn ON/OFF switch to the OFF (O) position.  
B Remove plug by prying with a small flathead  
screwdriver. Fig. 35  
C. Adjusting CO2:  
B Insert CO2 analyzer probe into the measuring port on  
the front right of the vent cap at an angle. The tip of  
the probe should be inserted to the middle of the vent  
cap (approx 5" inserted).  
Note: P1 adjustment will change the P2 reading.  
Confirm the P1 value BEFORE adjusting the P2 level.  
1. P1 CO2 level off:  
Note: Vent cap must be in place in order to measure  
CO2.  
B Loosen yellow painted Philips screw (1) and cover  
should rotate down (2) revealing a brass slotted  
screw. Fig. 37.  
B Adjusting the slotted screw counter clockwise will  
raise P1 CO2 levels and clockwise will lower P1  
CO2 levels. Adjustments to the slotted screw will  
also change P2 CO2 levels.  
2. P2 CO2 level off:  
B Remove yellow painted #40 Torx cover from the front  
of the gas valve. (Fig. 38) A plastic #40 Torx screw  
will be revealed.  
B Adjusting the plastic #40 Torx screw counter  
clockwise will lower P2 CO2 levels and clockwise  
will raise P2 CO2 levels.  
Fig. 35  
B While holding the Program (M) button, move the ON/  
OFF switch to ON (I) position (see Fig. 36). As soon  
as ‘188’ flashes on the display, release the Program  
button. The display should now read P2.  
Note: These screw adjustment are very sensitive and  
may take several minutes to stabilize.  
3. Verify both P1 and P2 are within the ranges specified  
in table 1 under the “With Front Cover” column. Repeat  
steps 1 and 2 as necesssary until CO2 values are within  
the specified ranges.  
Fig. 36  
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Special adjustment for measuring and adjusting CO2 levels  
D. Returning to Service:  
1. Return slotted cover to original position.  
2. Reinstall Torx cover.  
3. Remove CO2 analyzer probe and reinstall plug in  
exhaust collar.  
4. Turn ON/OFF switch to the OFF (O) position and  
then back to the ON (I) position.  
5. Heater is ready for normal operation.  
Without Front  
Cover  
With Front  
Cover  
Nat. Gas  
9.1 ± 0.1 %  
9.4 ± 0.1 %  
LP Gas  
Nat. Gas  
9.7 ± 0.1 %  
9.7 ± 0.1 %  
LP Gas  
max. input  
min. input  
P1  
P2  
Fig. 38  
max. input  
min. input  
P1  
P2  
10.1 ± 0.1 %  
10.4 ± 0.1 %  
10.7 ± 0.1 %  
10.7 ± 0.1 %  
* Final reading must be confirmed with the front cover  
on, CO2 levels increase when the cover is installed.  
Table 7  
Final Readings  
P2 CO2 Reading:  
% CO2  
% CO2  
P1 CO2 Reading:  
Fig. 37  
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10 Protecting the environment  
Packing  
The packing box may be fully recycled as confirmed by  
the recycling symbol  
.
Components  
Many parts in the heater can be fully recycled in the end  
of the product life. Contact your city authorities for  
information about the disposal of recyclable products.  
Saving water resources:  
B Make sure you close all the taps after any use. Avoid  
leaving the taps dripping. Repair any leaking tap.  
B Whenever possible use taps with built-in water flow  
limiters. They will give you the same comfort level  
while saving water.  
B Define the temperature you want, in the appliance or  
with the remote control. This way you have the  
precise water flow needed (mixing cold water to  
regulate temperature will increase the water flow with  
consequent waste of water).  
For increased safety shut off the appliance from  
the main water supply if your are staying away  
from home for a considerable time.  
At below freezing temperatures, disconnect the  
plumbing connections to the heater and allow  
the heater to drain.  
To prevent any freeze damage, introduce short  
bursts of compressed air (20-40 psi) through  
these connections to remove the residual water  
in the horizontal pipes and water valve.  
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Twelve Year Limited Warranty  
11 Twelve Year Limited Warranty  
General  
Service Labor Costs  
Aquastar water heaters are warranted by the  
Manufacturer (BOSCH) through Controlled Energy  
Corp. Controlled Energy Corp. (CEC) will furnish a  
replacement heat exchanger and will furnish a  
replacement of any other part which fails in normal use  
and service within the applicable periods specified  
below, in accordance with the terms of this warranty.  
The CEC replacement will be warranted for the  
unexpired portion of the original warranty. This warranty  
will be valid only for water heaters in possession of the  
original purchaser as recorded on the warranty card.  
This warranty does not cover any labor costs  
associated with service, removal or re-installation of  
part(s). All such costs must be borne by the Purchaser.  
Additionally, this warranty does not cover any labor  
costs associated with service, removal or re-installation  
of the original water heater or a replaced water heater.  
NOTE: the water heater must be free of  
damaging scale deposits and not subject  
i
to gas pressures greater than those  
shown on the rating plate, which must not  
be altered, defaced or removed.  
The Heat Exchanger  
How to Make a Claim  
If the heat exchanger fails within twelve (12) years after  
the original installation and operation, CEC will furnish  
a replacement heat exchanger. However, if the water  
heater is installed in other than a single family dwelling,  
this heat exchanger warranty is limited to two (2) years  
from date of original installation and operation.  
Any claim for warranty parts should be made by the  
original installer or service person to the local dealer,  
distributor or to CEC. If CEC, please contact the  
Technical Support Department:  
Controlled Energy Corp.  
340 Mad River Park  
Exceptions  
This warranty will not apply:  
Waitsfield, VT 05673  
1. to defects or malfunctions resulting from failure to  
properly install, operate or maintain the unit in  
accordance with the printed instructions provided;  
Phone: 800-642-3111  
2. to damage or abuse, accident, neglect or freezing  
and other acts of nature;  
In most cases, the dealer or distributor will be able to  
promptly honor your claim and subsequently notify  
CEC. However, all replacements are made subject to  
validation by CEC of in-warranty coverage. The  
damaged or defective item must be made available in  
exchange for the replacement.  
3. to damage resulting from operation with either the  
flame sensor rod or overheat sensor removed;  
4. to failure of the heat exchanger resulting from the  
operation of the water heater in a corrosive  
atmosphere or at water temperatures exceeding the  
maximum rating, or if the water heater is not supplied  
with potable water;  
Miscellaneous  
No one is authorized to make any other warranties on  
behalf of CEC. It is expressly understood that the  
replacement warranty of CEC shall be in lieu of any and  
all other warranties, express or implied, including  
warranties of merchantability or fitness for a particular  
use or purpose, and further that CEC shall not be liable  
for any loss or damage directly or indirectly arising from  
the use of the hot water heater, or for any consequential  
damages arising from such use (including damages  
from water leakage). CEC’s sole liability with respect to  
any defect shall be for the replacement of the defective  
part(s). Some states do not allow such limitations and  
exclusions, so the above may not apply to you.  
5. to defects or damage cause by any attachment  
or modification, including any energy-saving device.  
All Other Parts  
If any other part fails within two (2) years after original  
installation and operation, CEC will furnish  
replacement part free of charge.  
a
Shipping costs  
In addition to supplying the replacement part(s), CEC  
will provide ground service delivery for these parts.  
Expedited or upgraded shipping will be charged to the  
customer.  
This warranty gives specific legal rights. You may also  
have other rights which vary from state to state.  
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Ins taller Checklis t, to be performed by ins taller upon installation  
S erial Number  
___ ___ ___ ___ ___ ___ ___ ___  
(8 digit serial number is located on rating plate on right side panel)  
G as Pressure R eading*  
B uilding W ater Pressure  
Average W inter Temperature  
Average S ummer Temperature  
Installing C ompany  
Installer name  
S tatic__________  
Operating__________  
__________ R ange if on W ell system __________  
__________  
__________  
_____________________________________________  
_____________________________________________  
_____________________________________________  
_____________________________________________  
Address  
Phone  
* S ee C hapter 3.6 and gas pressure table (to be filled out by installer)  
Installation manual should be left with the owner after the installation is tested and completed  
VULC ANO Termodomésticos S .A.  
Estrada de C acia  
3801 - 856 Aveiro - PO R TUG AL  
Recycled paper  
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