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110 Indoor / 110 Outdoor Service Manual

Ver. 1.01

CONFIDENTIAL

Item #

Part #

Description

Common parts for other model

711

319143-052 Igniter

520, 310, 510, 910, 710

712

319143-039 High voltage igniter cable

520, 310, 510, 910

713

319143-185 Freeze protection thermostat

310, 510, 710

714

319143-220 Proportional gas valve wire

310

719

319143-212 Computer board cover

310

Summary of Contents for 110

Page 1: ...l Ver 1 01 1 CONFIDENTIAL 110 Direct Vent Indoor and Outdoor Models On Demand Water Heater Service Manual 110 Indoor A O Smith Water Products Company 500 Tennessee Waltz Parkway Ashland City TN 37015...

Page 2: ...onents in the interior view 8 5 Schematic diagram 10 6 Wiring diagram 11 7 Wiring diagram checkpoints for diagnosis 12 8 Resistance values of the temperature thermistors 14 9 Operational flow chart 15...

Page 3: ...tural 0 7 WC Water control Flow rate 0 75 to 6 6 GPM Available set temperatures 99 F to 167 F Default 122 F Temperature dipswitch settings 113 F 122 F 131 F 140 F Bypass valve N A Thermistors 2 thermi...

Page 4: ...8 123mm 120 VAC 7 3 4 196mm 1 3 4 45mm 1 3 4 45mm 1 7 8 47mm COLD 3 1 8 79mm HOT 5 1 4 133mm 120 VAC 1 3 8 36mm GAS 4 7 8 124mm 2 1 4 57 m m 13 1 8 334mm 6 1 4 160mm 1 10 2m m CO LD 2 1 4 5 6 mm HO T...

Page 5: ...7 8 123mm 120 VAC 7 3 4 196mm 1 3 4 45mm 1 3 4 45mm 1 7 8 47mm COLD 3 1 8 79mm HOT 5 1 4 133mm 120 VAC 1 3 8 36mm GAS 4 7 8 124mm 13 1 8 334mm C O L D 2 1 4 5 6 m m H O T 4 7 8 1 2 4 m m HOT 5 1 4 133...

Page 6: ...110 Indoor 110 Outdoor Service Manual Ver 1 01 6 CONFIDENTIAL 3 Interior view 110 Indoor 1 10 11 24 2 4 2 8 2 7 2 9 1 7 13 14 8 2 5 6 7 9 3 5 2 0 26 22 23 18 12 16 19 15 3 0...

Page 7: ...110 Indoor 110 Outdoor Service Manual Ver 1 01 7 CONFIDENTIAL 110 Outdoor 1 10 11 24 2 4 28 27 29 17 13 14 8 25 6 7 9 3 5 20 26 22 23 18 12 16 19 15 30...

Page 8: ...19143 182 310 510 6 Water inlet 404 319143 193 310 510 7 Water outlet 409 319143 194 310 510 8 Inlet thermistor 407 319143 214 310 9 Outlet thermistor 408 319143 218 310 10 Overheat cut off fuse 413 3...

Page 9: ...10 910 22 Air fuel ratio rod AFR rod 108 319143 339 23 Flame rod 108 319143 339 24 Igniter rod 109 319143 373 25 Inlet drain plug water filter 405 319143 197 310 510 26 120 VAC Power ON OFF switch 706...

Page 10: ...ites and flames appear inside the burner chamber 6 Water circulates through the heat exchanger and is heated up to the set temperature 7 Using thermistors to measure temperatures the computer modulate...

Page 11: ...former IG Igniter rod Heater Thermostat Heater Ground BK BK M V S V3 S V2 S V1 LB G O R O H C F H i l imit BL BL BL BL BL BL BL W Y BL O R FM W R Flow Sensor Flame rod Ground Air fuel ratio rod Y G O...

Page 12: ...VAC C Gas valves Light blue blue at COM MV 78 to 100 VDC during operation 0 9 to 1 3 k Green blue at COM SV1 78 to 100 VDC during operation 1 3 to 1 9 k Orange blue at COM SV2 78 to 100 VDC during op...

Page 13: ...on and 20 to 40 H2 Flow sensor Red Black 4 to 5 5 VDC White Black 1 to 4 VDC pulse 1 080 pulse min more than 18 Hz I Air fuel ratio rod Yellow AFR rod Between AFR rod and the computer board More than...

Page 14: ...85 4 90 4 12 Temperature F 122 131 140 149 158 167 176 185 194 203 212 C 50 55 60 65 70 75 80 85 90 95 100 Resistance k 3 49 2 96 2 53 2 16 1 86 1 60 1 39 1 21 1 05 0 92 0 81 Temperature F vs Resista...

Page 15: ...alse flame Igniter OFF Reignition Success OuTH OPEN or SHORT Fan motor fault MV OFF SV2 OFF GPV OFF SV1 SV3 OFF Fan motor stop operation Faucet closes Flow sensor OFF Remove cause Opeartion lamp OFF O...

Page 16: ...valve assembly 20 10 5 Flame rod 21 10 6 AFR rod 22 10 7 Heat exchanger 23 10 8 Flow adjustment valve 24 10 9 Flow sensor 25 10 10 Thermistors 26 10 11 Hi limit switch 27 10 12 Overheat cutoff fuse 28...

Page 17: ...ust or soot deposit on the burner surface 3 Cracks on the burners 4 Gas leakage from the burners Effects on the water heater if burners fails 1 Unexpected combustion 2 Unstable flame conditions and or...

Page 18: ...an cause poor combustion in the combustion chamber In this case the AFR rod will detect an improper flame condition and computer will take safety measures 2 Gas leakage from the manifold Error codes w...

Page 19: ...properly 2 Failure to ignite or abnormal ignition 3 Unstable combustion conditions Error codes when the fan motor fails 10 11 12 61 99 Diagnostic 1 Visual inspection connection breakage of wires or du...

Page 20: ...age of wires 2 Listen for clunk sounds from the gas valves opening right after fan motor initiates 3 Check voltages and resistance of coils proper range of values shown below Color Number of wires Blu...

Page 21: ...1 and or 12 error code s will display 2 The water heater will not initiate the ignition process The 72 error code will display Error codes when the flame rod fails 11 12 72 Diagnostic 1 Visual inspect...

Page 22: ...1 The Water heater will not initiate the ignition process The 72 error code will display 2 The fan motor speed cannot be modulated properly under abnormal flame conditions which can result in excessi...

Page 23: ...occurs an overheat cutoff fuse is in place to detect this event and immediately stop the water heater from operating 3 Abnormal sounds during combustion Error codes when the heat exchanger fails N A D...

Page 24: ...er components 2 Temperature fluctuations in the hot water output Error codes when flow adjustment valve fails N A Diagnostic 1 Visual inspection connection breakage of wires motor drive locked due to...

Page 25: ...itiate any operation Error codes when flow sensor fails N A Diagnostic 1 Visual inspection connection breakage of wires and or debris on impeller 2 Check voltages proper range of values shown below Co...

Page 26: ...e values are just off The water heater will have temperature fluctuations in hot water Error codes when thermistors fails 31 Outlet 32 Inlet Diagnostic 1 Visual inspection connection breakage of wires...

Page 27: ...rom the heat exchanger exceeds 185 F 85 C Note The outlet thermistor always act as backup hi limit detectors to detect excessively high water temperatures in the heat exchanger 2 The water heater is a...

Page 28: ...er instantly The 11 or 12 error code will display Failure events 1 Unable to detect the excessively high temperatures within the water heater Effects on the water heater if the overheat cutoff fuse fa...

Page 29: ...ontained in the heat exchanger to freeze up possibly causing the heat exchanger to burst Error codes when heaters fails N A Diagnostic 1 Visual inspection connection breakage of wires and the conditio...

Page 30: ...the computer board fails A component s may not operate within the water heater In most cases of computer board failure the whole the water heater does not operate at all Error codes will display Error...

Page 31: ...water heater if transformer fails 1 The water heater does not operate due to lack of power from transformer 2 A failed transformer can cause electrical damage to other electrical components within the...

Page 32: ...heater cannot ignite during the ignition process and the 11 or 12 error codes will display 2 No effects on the water heater however the durability of the igniter wears down Error codes when Igniter fa...

Page 33: ...ion thermostat fails 1 The freeze protection heaters will always be ON causing heat damage to components inside the water heater 2 The freeze protection heaters will never be able to turn on even unde...

Page 34: ...failure of the absorber Effects on the water heater if the Surge box fails 1 Unable to protect the computer board if high voltage gets applied to the unit The computer board can short out stopping all...

Page 35: ...6 Disconnection short circuit grounding of remote wires Normal 11 to 25 VDC between white black 7 Fault of PCB of remote control 1 Check for normal voltage at terminal It takes long time to get hot w...

Page 36: ...t gas out of the flue Abnormal sound from water heater 1 Check the gas type of the water r heater 2 Check how long the water heater has been installed and in use 3 Check the installation place 4 Check...

Page 37: ...16 VDC between red black J 7 Flow adjustment valve fault Normal 0 09 to 0 2 k between red black J Error Code Malfunction description Cancellation method 03 Incorrect dipswitch setting fault Turn off t...

Page 38: ...weak spark 1 Cracks soot on igniter rod 2 Improper gap between burner igniter rod Normal gap 0 16 4mm 3 PCB fault Normal 90 to 110 VAC at 7 purple purple during ignition 4 Igniter fault B 3 PCB fault...

Page 39: ...escription Cancellation method 12 Error code is shown after three failed attempts at ignition Loss of flame Turn off the power or water supply Diagnosis Checkpoint 1 Check gas supply and pressure Refe...

Page 40: ...Checkpoint 1 Outlet thermistor fault Refer to section 10 10 Visual inspection connection breakage of wires and or debris on thermistor Check voltage resistance between black black 113 Refer to Section...

Page 41: ...burn marks on the computer board 2 Main gas valve fault C Error Code Malfunction description Cancellation method 55 Fault of driving circuit for any of the gas solenoid valves SV1 SV2 and or SV3 Turn...

Page 42: ...er heater using the 9007666005 Visual inspection of PCB connection breakage of wires and or burn marks on the computer board G Error Code Malfunction description Cancellation method 70 1 PCB fault 1 F...

Page 43: ...rfect combustion Refer to section 12 3 Turn off the power or water supply If not possible press and hold the INC and DEC buttons on the computer board simultaneously for more than 3 sec Diagnosis Chec...

Page 44: ...terns for error codes 47 12 4 Clearing the 10 and 99 error code 48 12 5 AFR rod function 49 12 6 Dipswitch settings 50 12 7 A ON OFF conditions Overview 51 12 7 B ON OFF conditions BTU requirements 52...

Page 45: ...es 0 to 99 10 000 cycles 3 Inlet temperature 32 to 210 F Over 210 F E5 under 32 F E0 4 Outlet temperature 32 to 210 F Over 210 F E5 under 32 F E0 5 Air Fuel ratio rod current 0 to 99 A 6 Flow rate 0 0...

Page 46: ...ly 1 Check the power ON OFF switch of the water heater The factory setting is ON position 2 Turn on the power supply of the water heater 3 If the remote is installed Turn on the ON OFF button of the r...

Page 47: ...ode and is operating under normal conditions the red LED will remain solidly lit during operation and will remain completely OFF during stand by For details on the error code refer to p 35 43 Red LED...

Page 48: ...per sticking Vent Flaps installed on the Terminator Snow build up around Terminator Installed in a closet No Ventilation or lack of combustion air 6 If installed in laundry room check the burner and h...

Page 49: ...e AFR value is lower than the normal value the FM speed is decreased These values are read with the front cover close Measure the values after burning the water heater for ten minutes The AFR stage ca...

Page 50: ...ion OFF position 1 Gas type Propane Disable 2 Natural gas Disable 3 4 FM FM and FM FM speed is increased automatically See section 12 8 No 3 OFF position ON position No 4 OFF position 0 4 ON position...

Page 51: ...s needed to turn ON The BTU requirement is more than 29 800 BTU h OR Inlet temperature is lower 5 4 F than the set temperature and the BTU requirement is more than 14 880 BTU h Conditions needed to tu...

Page 52: ...10 Outdoor OFF 122 Tin 2 5 500 11 900 Tin 112 5 F The outlet temperature at that moment will be 120 F C ON OFF table Set temperature F Flow rate GPM 0 5 1 0 1 5 2 0 2 5 3 0 3 5 4 0 113 ON 53 5 83 2 93...

Page 53: ...nk of dipswitches No 4 OFF 1 2 000 to 4 000ft FM function the fan motor speed increased by 6 110 Indoor the fan motor speed increased by 4 110 Outdoor Bank of dipswitches No 3 ON Bank of dipswitches N...

Page 54: ...old connection otherwise proceed onto the next step 5 Press and hold down the MAX button on the computer board While holding down the MAX button press either the Increase or Decrease button to increas...

Page 55: ...6 After gas pressure has been set deactivate the 110 Indoor or 110 Outdoor remove the manometer tube and replace the port screw Figure 1 Figure 2 To Manometer Tube Increase button Computer board for...

Page 56: ...ocus on protecting the inlet and outlet piping inside the 110 Indoor or 110 Outdoor as well as the front drum pipe Ceramic heating blocks The blocks will only activate based on what the freeze protect...

Page 57: ...the all water flow has ceased close all hot water taps 6 Have a bucket or pan to catch the water from the drain plugs of the 110 Indoor or 110 Outdoor Unscrew the drain plugs to drain all the water ou...

Page 58: ...l Ver 1 01 58 CONFIDENTIAL 13 Components diagrams Case assembly 110 Indoor 110 Outdoor 002 050 70 2 05 2 007 7 04 0 06 0 05 0 53 066 05 3 052 052 00 1 004 0 56 002 050 702 052 007 704 006 005 053 066...

Page 59: ...712 701 053 120 053 712 711 053 714 062 055 119 151 118 052 121 703 053 704 705 401 104 105 101 709 111 052 053 112 113 114 708 053 067 055 053 706 053 059 103 115 058 713 150 061 059 101 709 111 102...

Page 60: ...Computer board assembly 110 Indoor Outdoor 110 Indoor Outdoor 4 02 4 61 4 58 0 52 4 15 0 64 4 60 4 56 4 04 40 6 4 0 5 45 4 40 7 4 57 4 5 6 4 6 0 4 0 9 45 5 41 0 45 4 40 8 0 64 0 53 1 53 15 4 1 5 2 C B...

Page 61: ...10 W Washer 052 319143 026 Screw M4 10 Coated 053 319143 060 Screw M4x10 054 319143 326 Hex head screw M4 12 W Washer 055 319143 063 Hex head screw M4x8 056 319143 372 Screw M4x10 057 319143 330 Screw...

Page 62: ...19143 160 Fan damper IN 118 319143 050 Gas inlet 520 310 510 119 319143 049 Gas inlet ring 520 310 510 120 319143 051 Igniter plate 520 310 510 910 710 121 319143 213 Surge box plate 310 150 319143 35...

Page 63: ...0 454 319143 082 O ring P4 FKM 520 310 510 910 710 455 319143 080 O ring P6 FKM 520 310 510 910 710 456 319143 100 O ring P14 FKM 520 310 510 457 319143 091 O ring P15 FKM 520 310 510 910 710 458 3191...

Page 64: ...ption Common parts for other model 711 319143 052 Igniter 520 310 510 910 710 712 319143 039 High voltage igniter cable 520 310 510 910 713 319143 185 Freeze protection thermostat 310 510 710 714 3191...

Page 65: ...door 110 Outdoor Service Manual Ver 1 01 65 CONFIDENTIAL 15 Revisions Version Description of changes Date 1 00 1 01 First edition Revision of wrong information in the section 1 4 and 12 6 11 01 10 12...

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