A.O. Smith BTH 120-250(A) manual

1 A DIVISION OF A.O. SMITH CORPORA TION Mc BEE, SOUTH CAROLINA PLACE THESE INSTRUCTIONS ADJACENT T O HEA TER AND NOTIFY OWNER TO KEEP FOR FUTURE REFERENCE. PRINTED IN U.S.A. 1 104 P ART NO. 196145-001 CYCLONE XHE ® Model BTH 120-250(A) SERIES 970 AND 973 COMMERCIAL GAS W A TER HEA TER GAS-FIRED POWER BURNER FOR DOMESTIC HOT W A TER Thank you for b[...]

2 These designs comply with the latest version of the American National S t andard for Gas W ater Heaters, V olume III, ANSI Z21.10.3 / CSA 4.3 M 98 as an automatic circulating tank water heater, and automatic storage water heaters. Detailed installation diagrams are found in this manual. These diagrams will serve to provide the installer with a re[...]

3 DANGER THIS W A TER HEA TER IS EQUIPPED WITH AN ADJUST ABLE THERMOST A T TO CONTROL W A TER TEMPERA TURE. HOT W A TER TEMPERA TURES REQUIRED FOR A UTOMA TIC DISHW ASHER AND LAUNDRY USE CAN CAUSE SCALD BURNS RESUL TING IN SERIOUS PERSONAL INJURY AND/ OR DEA TH. THE TEMPERA TURE A T WHICH INJURY OCCURS V ARIES WITH THE PERSON’S AGE AND THE TIME O[...]

4 that the water temperature be set for the lowest temperature which satisfies your hot water needs. This will also provide the most energy efficient operation of the water heater and minimize scale formation. SETTING THE W A TER HEA TER TEMPERA TURE A T 120°F/49°C WILL REDUCE THE RISK OF SCALDS. Some states require settings at specific lower tem[...]

5 • Do not cover the temperature & pressure relief valve. • Do not cover the instruction manual. Keep it on the side of the water heater or nearby for future reference. • Do obtain new labels from A.O. Smith for placement on the blanket directly over the existing labels. LOCA TING THE HEA TER W ARNING THERE IS A RISK IN USING FUEL BURNING[...]

6 less than 100 square inches (645 cm²). If the confined space is within a building of tight construction, air for combustion and ventilation must be obtained from outdoors. When directly communicating with the outdoors through vertical ducts, two permanent openings, located in the above manner , shall be provided. Each opening shall have a free a[...]

7 FIGURE 5 *NOTE: BTH 250 USES TEE ON AIR INT AKE TERMINAL DIRECT VENT HORIZONT AL VENT FIGURE 6 DO NOT TERMINA TE EXHAUST OVER PUBLIC AREA WHERE CONDENSA TE OR V APOR CAN CAUSE NUISANCE OR HAZARD. ON DIRECT VENT INST ALLA TIONS, EXHAUST VENT HOOD MUST BE LOCA TED 1' (30.5cm) MINIMUM FROM ANY OPENING IN BUILDING. ON DIRECT VENT INST ALLA TIONS[...]

8 TRANSMITTED INTO THE LIVING SP ACES. IMPORT ANT The vent system must terminate so that proper clearances are maintained as cited in local codes or the latest edition of the National Fuel Gas Code, ANSI Z223.1/NFP A 54 and for Canadian inst allations consult the Canadian Installation Codes and CAN/CGA B149.1 and .2. 1. Do not terminate the exhaust[...]

9 FIGURE 9 IMPORT ANT WHEN LOCA TING THE TERMINALS ON A SIDEWALL, THE FOLLOWING SPECIFICA TIONS PERT AINING TO TERMINAL LOCATION MUST BE FOLLOWED. 1. The intake vent terminal and the exhaust vent terminal must terminate on the same exterior wall and must be located at a minimum of 24" (61cm) from the vertical centerline of the exhaust vent ter[...]

10 FIGURE 12 INST ALLA TION OF VENT SYSTEM W ARNING THE OPTIONAL INT AKE VENTING ARRANGEMENT AND THE EXHAUST VENTING ARRANGEMENT MUST BE INSTALLED T O RUN DIRECTL Y TO THE OUTDOORS AND NOT IN ANY WA Y BE CONNECTED TO ANOTHER VENTING SYSTEM (I.E. FURNACE, DRYERS OR SP ACE HEA TERS). IT IS CRUCIAL THA T THE VENTING ARRANGEMENT BE KEPT SEP ARA TE FROM[...]

11 D . Know your own qualifications or those of your contractor . The solvent welding technique of joining PVC, PVC cellular core, ABS or CPVC pipe is a specialized skill just as any other pipe fitting technique. E . Closely supervise the installation and inspect the finished job before start-up. F . Contact the manufacturer , supplier , or compete[...]

12 BLOCKED OUTLET PROVER SWITCH (SEE FIGURE 13) The Blocked Outlet Prover Switch is set up to shut the unit off when a build- up of positive pressure in the exhaust vent pipe occurs. This switch is a positive pressure switch that requires an increase in pressure to change the electrical contacts from normally closed to open. When this switch preven[...]

13 CONNECTION OF GAS PIPE 1. When connecting gas pipe to unit, apply wrench to flange only . Note: Do not use wrench on gas valve or gas bracket. See Figure 15. 2. PERFORM THE GAS LEAK TEST ANY TIME WORK IS DONE ON A GAS SYSTEM TO A VOID THE POSSIBILITY OF FIRE OR EXPLOSION WITH PROPERTY DAMAGE, PERSONAL INJURY OR LOSS OF LIFE. FIGURE 15 The Gas Le[...]

14 4. When the system requires water for space heating at temperatures higher than required for domestic water purposes, a tempering valve must be installed. Please refer to installation diagrams on pages 23 through 28 in back of manual for suggested piping arrangements. HEA TER WIRING IF ANY OF THE ORIGINAL WIRE AS SUPPLIED WITH THE APPLIANCE MUST[...]

15 OPERA TION SEQUENCE OF OPERA TION T ypical Control/Appliance Operating Sequence 1. When the control is initially powered, it enters a test mode and will display the current software revision (example "104") for approximately 2 seconds, then "88.8" and all the LED's will illuminate for approximately 2 seconds. At this poi[...]

16 NO LOW VOL T AGE (Figure 20) 24V AC LED Off NO LOW VOL T AGE, 24V AC LED Off FIGURE 20 TEMPERA TURE PROBE FAULT (Figure 21) W ater T emp LED Flashing TEMPERA TURE PROBE FAUL T , Water T emp LED Flashing FIGURE 21 This condition accommodates multiple failure modes. T o more accurately determine the cause of failure, press the pushbutton on the di[...]

17 Display Flashes “05” when button is pressed: Display Flashes “15” when button is pressed: Display Flashes “25” when button is pressed: ECO SWITCH OPEN (Figure 22) ECO LED Flashing: ECO SWITCH OPEN, ECO LED Flashing FIGURE 22 CONTROL BAD (Figure 23) All LEDs Flashing: Possible Cause Remedy 1. This indicates the control has 1. Press bu[...]

18 ADJUSTMENT PROCEDURE INITIAL S T ART -UP A minimum gas supply pressure of 5.0" (1.25 kPa) W .C. (4.5" or 1.12 kPa) on BTH 150 and 199) for natural gas (1 1.0" or 2.74 kPa W .C. for L.P . Gas) is required before making any adjustment to the gas control pressure regulator Attempts to adjust the regulator during periods of low gas su[...]

19 FOR YOUR SAFETY READ BEFORE OPERA TING W ARNING: If you do not follow these instructions exactly , a fire or explosion may result causing property damage, personal injury or loss of life.[...]

20 W ARNING UNDER NO CIRCUMST ANCES SHOULD THE INPUT EXCEED THE RA TE SHOWN ON THE HEA TER RA TING PLA TE. OVERFIRING COULD RESUL T IN DAMAGE OR SOOTING OF THE HEA TER. CA THODIC PROTECTION CAUTION HYDROGEN GAS CAN BE PRODUCED IN A HOT W A TER SYSTEM SER VED BY THIS HEA TER THA T HAS NOT BEEN USED FOR A LONG PERIOD OF TIME (GENERALL Y TWO WEEKS OR [...]

21 FIGURE 25 T o dissolve and remove the more stubborn mineral deposits, A.O. Smith UN•LIME® Professional Delimer should be used. A.O. Smith UN•LIME® Professional Delimer is an easy to handle patented food grade acid formulated specifically for lime scale removal from all types of water using equipment. Available in 1 gallon (3.8L) (part no. [...]

22 T o inspect or replace an anode: The anodes on this heater are easily accessible from the top of the heater making replacement simple and quick. 1. Turn the heater off per the lighting instructions. Connect a hose to the drain valve . Locate the hose's discharge in an area where hot water will not cause any damage or injury . 2. Open the dr[...]

23 ONE TEMPERA TURE - ONE HEA TER HORIZONT AL ST ORAGE T ANK FORCED CIRCULA TION WITH OR WITHOUT BUILDING RECIRCULA TION DANGER TEMPERA TURE SETTING SHOULD NOT EXCEED SAFE TEMPERA TURE A T FIXTURES. SEE W A TER TEMPERA TURE CONTROL W ARNING ON PAGE 4. IF HIGHER PREHEA T TEMPERA TURES AR E NECESSAR Y TO OBT AIN ADEQUATE BOOSTER OUTPUT , ADD AN ANTI-[...]

24 * PIPE RELIEF V A L VE TO OPEN DRAIN. NOTE: IF TEMPERED WA TER IS RECIRCULA TED, RETURN LINE SHOULD BE CONNECTED A T POINT “A”. INST ALL IN ACCORDANCE WITH LOCAL CODES. TWO TEMPERA TURE - ONE HEA TER HIGH TEMPERA TURE WITH OR WITHOUT BUILDING RECIRCULA TION DANGER TEMPERA TURE SETTING SHOULD NOT EXCEED SAFE TEMPERA TURE A T FIXTURES. SEE WA [...]

25 TWO TEMPERA TURE - TWO HEA TERS HIGH TEMPERA TURE WITH OR WITHOUT BUILDING RECIRCULA TION TWO TEMPERA TURE - THREE HEA TERS (TWO PRE-HEA TERS/ONE BOOSTER HEA TER) WITH OR WITHOUT BUILDING RECIRCULA TION MUST BE IDENTICAL HEA TERS FOR MUL TIPLE HEA TER INST ALLA TION SEE MANIFOLD KIT SPECIFICA TIONS, P AGE 28. CAUTION: IF BUILDING COLD W A TER SU[...]

26 * PIPE RELIEF V A L VE TO OPEN DRAIN * * 140°F (60°C)TO 150°F (66°C) SHOULD BE MAXIMUM WA TER TEMPERA TURE MAINT AINED IN THE PRE-HEA TERS. 120°F (49°C) SHOULD BE THE MINIMUM TEMPERA TURE OF W A TER IN THE PRE- HEA TERS. CONNECT CIRCULA TING LINE FROM FIXTURES, IF USED, T O COLD W A TER SUPPL Y LINE OF PRE-HEA TER. CONNECT CIRCULA TING LIN[...]

27 NOTE 1: TOGGLE SWITCH CONTROLS 180°F (82°C) WA TER CIRCULA TION. INST ALL ON OR CLOSE TO DISHW ASHER. TOGGLE SWITCH MUST BE CLOSED (ON) DURING THE RINSE OPERA TION AND OPEN (OFF) WHEN DISHW ASHER IS NOT OPERA TING OR WHEN ON LONG ST ANDBY . NOTE 2: INST ALL LINE TEMPERA TURE CONTROL IN AN UNINSULA TED TEE BEYOND THE DISHWASHER T AKEOFF IN THE [...]

28 MANIFOLD KITS Precision cut type “L” all copper A.O. Smith manifold kits assure water flow balance of all units. Without this balance, the full water heating and storage potential of the system cannot be achieved. Plus, the units with the higher water flow may have a shortened life. Unions shown in piping diagrams are not included in the man[...]

29 CHECKLIST AND SERVICE INFORMA TION IMPORT ANT The installer may be able to observe and correct certain problems which might arise when the unit is put into operation or when it is re-fired after a prolonged shutdown. HOWEVER, it is recommended that only qualified servicemen, using appropriate test equipment, be allowed to service the heater . BE[...]

30 MOTOR WILL NOT RUN 1. Confirm 120V AC to the controller . Also, to verify correct polarity , check for 120 V AC between hot supply and ground. If there is no voltage, check for a loose connection where it connects to the controller . 2. If there is 120 volts to the controller , check for loose connections or a locked rotor . If the rotor cannot [...]

31 Model BTH Limited W arranty A. O. Smith Corporation, the warrantor , extends the following LIMITED WARRANTY to the owner of this water heater . 1. THE T ANK If the glass-lined tank in this water heater shall prove upon examination by the warrantor to have leaked due to natural corrosion from potable water therein, during the first THREE years af[...]

32 A.O. SMITH WATER PRODUCTS COMPANY 5621 W. 115TH STREET • ALSIP, ILLINOIS 60803 PHONE: 1-800-433-2545 • FAX: 1-800-433-2515 www.hotwater.com • E-MAIL: parts@hotwater.com[...]