A.O. Smith 510, Service Manual

Page 1: ...l Ver 1 00 1 CONFIDENTIAL 510 Direct Vent Indoor and Outdoor Models On Demand Water Heater Service Manual 510 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: ...ow rate 0 75 to 10 0 GPM Available set temperatures 99 to 185 F default 122 F Temperature dipswitch settings 104 F 113 F 122 F 131 F 140 F 158 F 176 F 185 F Bypass valve Yes Thermistors 3 thermistors...

Page 4: ...mm COLD 3 1 4 84mm 4 3 8 113mm 1 5 8 4 3m m 1 9 3 8 49 3 m m COLD 2 7 8 71mm 1 26mm HOT 6 1 2 164mm 9 1 2 241mm 120VAC 3 7 8 99mm GAS 5 1 4 135mm 2 Exterior view Top view Bottom view Side view Front v...

Page 5: ...7 8 47mm HOT 5 1 4 133mm 120V 1 3 8 36mm GAS 4 7 8 124mm COLD 3 1 4 84mm 4 3 8 113mm 1 9 3 8 4 93 m m COLD 2 7 8 71mm 1 26mm HOT 6 1 2 164mm 9 1 2 241mm 120VAC 3 7 8 99mm GAS 5 1 4 135mm 1 5 8 43 m m...

Page 6: ...510 Indoor 510 Outdoor Service Manual Ver 1 00 6 CONFIDENTIAL 3 Interior view 510 Indoor 1 3 4 5 6 7 9 8 31 10 11 13 14 15 16 17 18 18 19 2 21 12 23 24 32 25 22 28 29 27 30 20 26...

Page 7: ...510 Indoor 510 Outdoor Service Manual Ver 1 00 7 CONFIDENTIAL 510 Indoor 1 3 4 5 6 7 9 8 31 10 11 13 14 15 16 17 18 18 19 2 21 12 23 24 32 25 22 28 29 27 30 2 0 26...

Page 8: ...404 319143 193 110 310 7 Water outlet 409 319143 194 110 310 8 Inlet thermistor 407 319143 085 9 Mixing thermistor 408 319143 190 10 Overheat cut off fuse 413 319143 149 110 310 910 11 Burner assembly...

Page 9: ...ame rod 108 319143 035 24 Igniter rod 109 319143 037 25 Inlet drain plug water filter 405 319143 197 110 310 26 120 VAC Power ON OFF switch 706 319143 141 110 310 520 27 Gas valve assembly Included in...

Page 10: ...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 modulates the gas and water va...

Page 11: ...Green Y Yellow O Orange BR Brown BK W R B K W R W R R Flow Sensor W Bypass Valve Flame rod Ground AFR rod Y G O Inlet thermistor Output thermistor Mixing thermistor Remote controller Pump connectors...

Page 12: ...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 operation 1 3 to 1 9 k Red blue at COM SV3 78 to 100 VD...

Page 13: ...C 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 0 5 A during operation Flame rod Orange Flame rod Be...

Page 14: ...e k 23 76 19 08 15 43 12 56 10 28 8 47 7 02 5 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...

Page 15: ...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 Operation stop YES NO YES NO NO YES YES NO 20sec later YES NO...

Page 16: ...bly 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 Bypass valve 26 10 11 Thermistors 27 10 12 Hi limit switch 28 10 13 Overheat cut...

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: ...ause 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 when...

Page 19: ...ure to ignite or abnormal ignition 3 Unstable combustion conditions Error codes when the fan motor fails 101 111 121 611 991 Diagnostic 1 Visual inspection connection breakage of wires or dust causing...

Page 20: ...on breakage 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 w...

Page 21: ...or 121 error code s will display 2 The water heater will not initiate the ignition process The 721 error code will display Error codes when the flame rod fails 111 121 721 Diagnostic 1 Visual inspecti...

Page 22: ...water heater will not initiate the ignition process The 721 error code will display 2 The fan motor speed cannot be modulated properly under abnormal flame conditions which can result in excessive CO...

Page 23: ...lace 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 Diagnostic 1 Visual inspection soot dep...

Page 24: ...the hot water output 3 Within an Easy Link system the 651 error code can occur Error codes when flow adjustment valve fails 651 only within Easy Link systems Diagnostic 1 Visual inspection connection...

Page 25: ...ny operation Error codes when flow sensor fails 441 only within Easy Link systems Diagnostic 1 Visual inspection connection breakage of wires and or debris on impeller 2 Check voltages proper range of...

Page 26: ...properly Effects on the water heater if bypass valve fails 1 Water leakage from failed valve can damage other water heater components 2 Temperature fluctuations in the hot water output Error codes whe...

Page 27: ...he water heater will have temperature fluctuations in hot water Error codes when thermistors fails 311 Output 321 Inlet 331 Mixing Diagnostic 1 Visual inspection connection breakage of wires and or de...

Page 28: ...the heat exchanger exceeds 194 F 90 C Note The mixing and output thermistors always act as backup hi limit detectors to detect excessively high water temperatures in the heat exchanger 2 The water hea...

Page 29: ...r instantly The 111 or 121 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 f...

Page 30: ...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 31: ...ects on the water heater if 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 Er...

Page 32: ...e 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 t...

Page 33: ...ater cannot ignite during the ignition process and the 111 or 121 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 34: ...f the freeze protection 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...

Page 35: ...failure of the absorber Effects on the water heater if the fuse 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 36: ...ck F 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 h...

Page 37: ...t gas out of the flue Abnormal sound from water heater 1 Check the gas type of the water heater 2 Check how long the water heater has been installed and in use 3 Check the installation place 4 Check t...

Page 38: ...7 Flow adjustment valve fault Normal 0 09 to 0 2 k between red black J Error Code Malfunction description Cancellation method 031 Incorrect dipswitch setting fault Turn off the power or water supply D...

Page 39: ...res and or observed 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 B 3 PCB fa...

Page 40: ...ult During operation more than 1 A through the flame rod wire orange I 8 Check if hi limit switch is properly functioning Error Code Malfunction description Cancellation method 121 Error code is shown...

Page 41: ...int 1 Output thermistor fault Refer to section 10 11 Visual inspection connection breakage of wires and or debris on thermistor Check voltage resistance between black black 12 Refer to Section 8 for p...

Page 42: ...tion description Cancellation method 510 Fault of driving circuit for main gas solenoid valve MV SV1 SV2 and or SV3 Turn off the power supply The computer checks the condition of the main gas valve im...

Page 43: ...the water heater using the diagnostics mode of the 9007603005 temperature remote controller See the 12 1 How to diagnose the water heater using the 9007603005 Visual inspection of PCB connection brea...

Page 44: ...the gas proportional valve Normal 20 to 40 between white red H1 Error Code Malfunction description Cancellation method 721 False flame detection Turn off the power or water supply Diagnosis Checkpoin...

Page 45: ...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 Checkpoint 1 Check the gas ty...

Page 46: ...in the Easy link system 55 12 7 A ON OFF conditions Overview 56 12 7 B ON OFF conditions BTU requirements 57 12 8 A Pump control ON OFF conditions Only for single and Easy link system 58 12 8 B Pump c...

Page 47: ...pressing the HOT or COLD buttons Fig 1 shows mode 5 being selected When selecting information please refer to the table on p 49 for the proper mode 3 Press the INFO button to select the mode and the i...

Page 48: ...n Easy link system of 510 Indoor or 510 Outdoor a maximum of four units of the 510 Indoor or 510 Outdoor s can be linked together 4 Press the INFO button to select the desired unit 5 When the desired...

Page 49: ...minutes After 720 the next rotation occurs Air Fuel ratio rod current 0 to 999 0 1 A 8 ON OFF cycles during current rotation 0 to 100 cycles After 100 the next rotation occurs Flow rate 0 to 999 0 1 G...

Page 50: ...ght in a circular 0 pattern one segment at a time Displaying error code history 1 Briefly press the Error call button do not hold down the button 2 If the 510 Indoor or 510 Outdoor has had prior error...

Page 51: ...t Damper 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...

Page 52: ...is increased If the 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 the water heater for ten minutes The AF...

Page 53: ...ging any settings The functions of the upper bank of dipswitches No Functions ON position OFF position 1 Gas type Propane Disable 2 Natural gas Disable 3 Allow adjustments of fan motor speed Changing...

Page 54: ...lt 2 Model type Default 510 Indoor Disable 3 Default 510 Outdoor Disable 4 5 6 Output temperature settings See table to the right Default 122 F OFF ON 1 2 3 4 5 6 OFF ON 1 2 3 4 5 6 OFF ON 1 2 3 4 5 6...

Page 55: ...mputer board of all child units for at least 5 seconds 2 The 7 seg LED on the computer board of all child units will display 0 to signify that the computer memory has been erased of its previously ass...

Page 56: ...r 510 Outdoor ON OFF Conditions Conditions needed to turn ON The BTU requirement is more than 14 880 BTU h AND The water flow rate is more than 0 75 GPM Conditions needed to turn OFF The BTU requireme...

Page 57: ...ature 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 2 98 1 101 1 103 1 104 5 105 6 OFF 65 4 89 2 97 1 101 1 103 5 105...

Page 58: ...ation pump to be controlled by the following conditions ON OFF Conditions Re circulation mode Conditions that activate the pump The BTU requirement is more than 18 600 BTU h OR 30 minutes have elapsed...

Page 59: ...the pump OFF 120 Tin 2 5 500 14 880 Tin 108 1 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 38 6 75 8 88 2 94 4 98 1 100 6 102 4 103 7 OFF 53 8 83 4 93 3 98...

Page 60: ...C GPM L min 100 122 37 50 3 4 13 131 55 3 2 12 140 60 2 9 11 149 65 2 6 10 158 167 70 75 2 4 9 176 185 80 85 2 1 8 2 Condition required to reduce the number of activated 510 Indoors or 510 Outdoors A...

Page 61: ...bank of dipswitches No 4 OFF No 5 OFF 1 2 000 to 4 000ft FM function the fan motor speed increased by 6 510 Indoor the fan motor speed increased by 4 510 Outdoor Left bank of dipswitches No 4 ON No 5...

Page 62: ...current value through the coil will not exceed 1 amp For example To the right there is a sample of relay specifications from an arbitrary brochure You can select either the 120 VAC or 240 VAC relay be...

Page 63: ...fold 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 increa...

Page 64: ...ired value 6 After gas pressure has been set deactivate the 510 Indoor or 510 Outdoor remove the manometer tube and replace the port screw Computer board Figure 3 MAX button MIN button Increase button...

Page 65: ...own the MAX button on the computer board While holding down the MAX button press either the Increase or Decrease button to increase or decrease the fan motor speed respectively Figure 2 Refer to the r...

Page 66: ...oor As long as each particular feature s activation requirements are met it is possible for both features to operate at the same time Automatic firing system Activation conditions will depend on the o...

Page 67: ...continually check the temperatures of the inlet and output thermistors The automatic firing system will not activate at all unless these 25 minutes have elapsed When the computer checks for these temp...

Page 68: ...mostat is located on the fan motor close in vicinity to the inlet and outlet pipes within the 510 Indoor or 510 Outdoor Electrical power is required for this feature to operate The heating blocks will...

Page 69: ...ut off valve 5 Open all hot water taps in the house When 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 510 Indoor or 510...

Page 70: ...Ver 1 00 70 CONFIDENTIAL 13 Components diagrams Case assembly 510 Indoor 510 Outdoor 004 001 0 02 0 50 702 052 0 07 704 006 005 053 066 053 052 052 056 05 2 004 0 01 0 52 0 03 0 02 0 50 702 052 0 07 7...

Page 71: ...711 053 714 062 055 053 117 401 059 060 103 401 104 105 052 053 1 12 113 114 708 0 67 066 055 062 053 A A 116 1 50 061 119 151 118 052 101 709 111 101 709 111 701 053 053 712 102 053 510 Indoor Outdoo...

Page 72: ...5 410 454 408 064 403 4 62 458 4 60 4 56 454 411 45 9 053 153 154 152 463 413 452 450 4 53 451 414 B C C B 401 41 4 412 063 401 Computer board assembly 510 Indoor Outdoor Water way assembly 707 710 70...

Page 73: ...rew M4 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 33...

Page 74: ...10 310 910 114 319143 045 Manifold gasket B 520 110 310 910 115 319143 367 Fan damper 310 116 319143 042 Pressure port for 520 310 910 710 117 319143 041 Combustion chamber tube IN 520 310 319143 344...

Page 75: ...g plate 520 110 310 910 710 451 319143 125 Heater fixing plate 16 520 110 310 910 710 452 319143 066 Fuse fixing plate 18 520 110 310 910 710 453 319143 146 Fuse fixing plate 14 110 310 454 319143 082...

Page 76: ...0 310 710 319143 187 EH IG wire 319143 210 EH IG wire with freeze protection thermostat 110 310 711 319143 052 Igniter 520 110 310 910 710 712 319143 039 High voltage igniter cable 520 110 310 910 713...

Page 77: ...510 Indoor 510 Outdoor Service Manual Ver 1 00 77 CONFIDENTIAL 15 Revisions Version Description of changes Date 1 00 First edition 11 01 10...