A.O. Smith 400A - Manuals

5 The temperature may be adjusted from 80°F/27°C to 180°F/82°C.The thermostat was adjusted to 120°F/49°C before the heaterwas shipped from the factory. It is recommended that lower watertemperatures be used to avoid the risk of scalding. It is furtherrecommended, in all cases, that the water tempera...

6 THE HEATER SHALL BE LOCATED OR PROTECTED SO IT ISNOT SUBJECT TO PHYSICAL DAMAGE BY A MOVING VEHICLE. DO NOT LOCATE THE HEATER WHERE NOISE FROM THEE X H A U S T O R I N TA K E W I L L B E O B J E C T I O N A B L E . T H I SI N C L U D E S L O C AT I O N S C L O S E T O O R A C R O S S F R O MWINDOW...

7 CLEARANCES These heaters are approved for installation on combustible flooringin an alcove when the minimum clearances from any combustionconstruction are followed as indicated in Figure 4. In all installations the minimum combustible clearances from anyvent piping shall be 0". Vent piping pas...

10 H e a t e r m u s t b e p r o t e c t e d f r o m f r e e z i n g d o w n d r a f t s d u r i n gshutdown periods. WARNING NEVER OPERATE THE HEATER UNLESS IT IS VENTED TOTHE OUTDOORS AND HAS ADEQUATE AIR SUPPLY TO AVOIDRISKS OF IMPROPER OPERATION, FIRE, EXPLOSION ORASPHYXIATION. VENT PIPE TERMINA...

11 2. The horizontal centerline of the intake vent terminal may not be located lower than the horizontal centerline of the exhaust ventterminal (see Figure 9). FIGURE 9. INSTALLATION SEQUENCE For installations in the City of Los Angeles, California Category IVPVC Pipe such as that manufactured by Br...

12 2. Drill a pilot hole approximately 1/4" (6 mm) outside of the marked circle. This pilot hole is used as a starting point for a saws-all ors a b r e s a w b l a d e . C u t a r o u n d t h e m a r k e d c i r c l e s t a y i n gapproximately one quarter inch outside the line. (This will allow...

13 VENT PIPE PREPARATION 1. INITIAL PREPARATION A. Make sure the solvent cement you are planning to use isdesigned for the specific application you are attempting. B. K n o w t h e p h y s i c a l a n d c h e m i c a l c h a r a c t e r i s t i c s a n d limitations of the PVC, PVC cellular core, AB...

14 HOT SURFACE IGNITER The Hot Surface Igniter is a device that ignites the main burner byhigh temperature (>1800°F or >982°C). When 120VAC is appliedto the igniter, sufficient heat is generated to ignite the main burner.Although improvements have been made to strengthen the igniter,it is frag...

15 OR LESS, THE APPLIANCE NEED NOT BE DISCONNECTED, BUTMUST BE ISOLATED FROM THE SUPPLY PRESSURE TEST BYCLOSING THE MANUAL GAS SHUTOFF VALVE. BEFORE PLACING THE HEATER IN OPERATION, CHECK FORGAS LEAKAGE. USE SOAP AND WATER SOLUTION OR OTHERMATERIAL ACCEPTABLE FOR THE PURPOSE OF LOCATING GASLEAKS. DO...

16 2. Toxic chemicals, such as those used for boiler treatment, shall NEVER be introduced into this system. 3. This unit may never be connected to any existing heating system or component(s) previously used with non-potablewater heating appliance. 4. W h e n t h e s y s t e m r e q u i r e s w a t e...

17 FIGURE 16. OPERATION SEQUENCE OF OPERATION Typical Control/Appliance Operating Sequence 1. When the control is powered, it should first display “0”, thenthe input line voltage (“120”), the calibration setting (12), thenthe actual water temperature in the tank. 2. If the control determines that th...

20 DO NOT USE THIS HEATER IF ANY PART HAS BEEN UNDERWAT E R . I M M E D I AT E LY C A L L A Q U A L I F I E D S E R V I C ETECHNICIAN TO INSPECT THE HEATER AND TO REPLACE ANYPART OF THE CONTROL SYSTEM AND ANY GAS CONTROLWHICH HAS BEEN UNDER WATER. LIGHT THE UNIT IN ACCORDANCE WITH THE OPERATINGINSTR...

21 LIGHTING AND OPERATION INSTRUCTIONS A. This appliance does not have a pilot. It is equippedwith an ignition device which automatically lights theburner. Do not try to light the burner by hand. B. BEFORE OPERATING smell all around the appliance areafor gas. Be sure to smell next to the floor becau...

22 WARNING UNDER NO CIRCUMSTANCES SHOULD THE INPUT EXCEEDT H E R AT E S H O W N O N T H E H E AT E R R AT I N G P L AT E .OVERFIRING COULD RESULT IN DAMAGE OR SOOTING OF THEHEATER. CATHODIC PROTECTION CAUTION HYDROGEN GAS CAN BE PRODUCED IN A HOT WATER SYSTEMSERVED BY THIS HEATER THAT HAS NOT BEEN U...

25 CAUTION BEFORE MANUALLY OPERATING THE VALVE, MAKE SURE THATA DRAIN LINE HAS BEEN ATTACHED TO THE VALVE TO DIRECTTHE DISCHARGE TO AN OPEN DRAIN. FAILURE TO TAKE THISPRECAUTION COULD MEAN CONTACT WITH EXTREMELY HOTWATER PASSING OUT THE VALVE DURING THIS CHECKINGOPERATION. I f t h e t e m p e r a t ...

26 ONE TEMPERATURE - ONE HEATER HORIZONTAL STORAGE TANK FORCED CIRCULATION WITH OR WITHOUT BUILDING RECIRCULATION DANGER TEMPERATURE SETTING SHOULD NOT EXCEEDSAFE TEMPERATURE AT FIXTURES. SEE WATERTEMPERATURE CONTROL WARNING ON PAGE 3.I F H I G H E R P R E H E AT T E M P E R AT U R E S A R ENECESSAR...

27 * PIPE RELIEF VALVE TO OPEN DRAIN. N O T E : I F T E M P E R E D WAT E R I S RECIRCULATED, RETURN LINE SHOULD BECONNECTED AT POINT “A”. INSTALL IN ACCORDANCE WITH LOCALCODES. TWO TEMPERATURE - ONE HEATER HIGH TEMPERATURE WITH OR WITHOUT BUILDING RECIRCULATION DANGER TEMPERATURE SETTING SHOULD NOT...

28 TWO TEMPERATURE - TWO HEATERS HIGH TEMPERATURE WITH OR WITHOUT BUILDING RECIRCULATION TWO TEMPERATURE - THREE HEATERS (TWO PRE-HEATERS/ONE BOOSTER HEATER) WITH OR WITHOUT BUILDING RECIRCULATION MUST BE IDENTICAL HEATERS FOR MULTIPLE HEATER INSTALLATION SEE MANIFOLD KITSPECIFICATIONS, PAGE 30. CAU...

31 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 waterheating 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...

32 CHECKLIST AND SERVICE INFORMATION IMPORTANT The installer may be able to observe and correct certain problemswhich might arise when the unit is put into operation or when it isre-fired after a prolonged shutdown. HOWEVER, it is recommendedthat only qualified servicemen, using appropriate test equ...

34 Model BTH Limited Warranty A. O. Smith Corporation, the warrantor, extends the following LIMITED WARRANTY to the owner of this water heater. 1. THE TANK 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 ...