John wood water heater troubleshooting

John Wood 6-120 water heater troubleshooting

ProblemPossible Cause(s)Corrective Action
WATER LEAKS (See Leakage Checkpoints on page 19)Improperly sealed, hot or cold supply connection, relief valve or drain valve.Seal and tighten threaded connections.
Leakage from other appliances or water lines.Inspect other appliances near water heater.
NO HOT WATERNo power to heater.Turn on electrical switch. Check for blown fuses or tripped breaker.
Non-functioning upper element.Replace element.
High Temperature Limit Switch open.Reset. Check for source of trouble and correct.
Non-functioning upper thermostat.Replace thermostat.
INSUFFICIENT HOT WATERNon-functioning thermostats.Replace thermostats.
Non-functioning lower element.Replace element.
Improper calibration.Replace thermostats.
Thermostats set too low.Set thermostats to desired temperature.
Sediment or lime in tank.Drain. Determine if water treatment is needed.
Heater too small for job.Install water heater of adequate capacity.
Wrong piping connections.Correct piping.
Leaking faucets.Repair faucets.
Wasted hot water.Review and reduce hot water consumption.
Long runs of exposed pipe.Insulate piping.
Hot water piping on outside wall.Insulate piping.
HIGH OPERATION COSTSImproper Calibration.Replace thermostats.
Thermostats set too high.Set thermostat to desired setting.
Sediment or lime in tank.Drain. Flush-Provide water treatment if needed.
Heater too small for job.Install water heater of adequate capacity.
Wrong piping connections.Correct piping.
Leaking faucets.Repair faucets.
Wasted hot water.Review and reduce hot water consumption.
Long runs of exposed piping.Insulate piping.
Hot water piping in exposed wall.Insulate piping.
SLOW HOT WATER RECOVERYNon-functioning upper element.Replace element.
Non-functioning lower element.Replace element.
DRIP FROM RELIEF VALVEExcessive water pressure.Use Pressure Reducing Valve and Pressure Relief Valve.
Closed system.See “Thermal Expansion” in the For Your Information section.
THERMOSTAT DOES NOT SHUT OFFNon-functioning thermostats.Replace thermostats.
Improper calibration.Replace thermostats.
WATER ODORSulfides in the water.See “Operational Conditions” in the For Your Information section.
WATER HEATER SOUNDSScale accumulation on elements.Contact dealer to clean or replace elements.

John Wood 4040SN-PDV water heater troubleshooting

SYMPTOMPOSSIBLE CAUSE(S)CORRECTIVE ACTION
BLOWER WILL NOT START.1. No Power to unit.1. Plug in power cord, check fuses/supply voltage.
2. Thermostat setting too low.2. Increase thermostat temperature setting.
3. Defective air pressure switch (must be open at start-up before blower is energized).3. Replace air pressure switch.
4. Defective blower.4. Replace blower.
5. Disconnected or loose wire.5. Repair/reconnect wires.
6. Control locked-out.6. Reset - determine cause of lockout.
BLOWER RUNS CONTINUOUSLY.1. Air pressure switch not closing due to insufficient draft - check for:1. Determine cause of insufficient draft. Check draft with manometer at pressure switch (refer to Table 3 for minimum acceptable draft settings).
a. vent piping blocked,a. remove blockage,
b. piping length too long,b. reduce vent length/increase vent size,
c. frozen vent termination,c. clear termination of snow/ice,
d. clogged/dirty blower.d. clean blower wheel.
2. Disconnected, torn or blocked pressure sensing tubing from air pressure switch to blower housing.2. Reconnect or replace pressure sensing tubing.
3. Air pressure switch not closing due to defective switch.3. Replace defective pressure switch.
4. High limit switch open due to excessive vent temperature or defective switch.4. Determine cause of overheating check for: overfiring, insufficient air supply, high ambient air temperature (once activated high limit must be replaced).
HOT SURFACE IGNITER NOT GLOWING FOLLOWING WARM-UP PERIOD1. 120VAC polarity reversed at 120VAC outlet receptacle.1. Reverse polarity at 120VAC outlet receptacle.
2. Defective hot surface igniter.2. Replace igniter (Check for 120VAC across 11 & 12, Robertshaw only).
3. Defective Control.3. Replace control.
CONTROL LOCKED-OUT.1. No gas supply.1. Check/turn on gas supply.
2. Gas control switch in “OFF" position.2. Turn control switch to “ON” position (Robertshaw only)
3. Insufficient gas supply.3. Ensure correct supply pressure for gas type (Nat Gas 7.0 in. w.c. (1.74 kPa)) (Propane 11.0 in. w.c.(2.74 kPa)).
4. Incorrect manifold gas pressure.4. Check/adjust for correct manifold gas pressure (NG 3.5 in. w.c.(0.87 kPa)), (Propane 10.0 in. w.c. (2.49 kPa)).
5. Incorrect gas type.5. Ensure correct gas type for water heater model.
6. Defective igniter/loose or disconnected wire.6. Replace defective igniter/reconnect wiring.
7. Improperly positioned, dirty, or defective flame rod/loose or disconnected wire.7. Reposition, clean, or replace defective flame rod/reconnect wiring.
8. Burner orifice clogged.8. Remove obstruction.
9. Blocked water heater flue.9. Remove blockage/clean flue.
10.Defective control.10. Replace Control. * See Figure 26.
CONTROL LOCKED-OUT. SOLID GREEN LED.1. Internal control fault.1. Replace control.
2. ECO failure - excessive water temperature.2. Replace control.
3. Excessive humidity/damp environment.3. Allow control to dry.

John Wood 324334-001 water heater troubleshooting

PROBLEMPOSSIBLE CAUSE(S)CORRECTION
BURNER WILL NOT IGNITE1. Pilot not lit1. Light pilot
2. Thermostat set too low2. Turn temp, dial to desired temperature
3. No gas3. Check with gas utility company
4. Dirt in the gas lines4. Notify utility-install trap in gas line
5. Pilot line clogged5. Clean, locate source and correct
6. Main bumer line clogged6. Clean, locate source and correct
7. Defective thermopile7. Replace thermopile
8. Defective gas control/thermostat8. Replace gas control/thermostat
SMELLY WATER1. Sulfur in the water1. Replace the anode with a special anode
BURNER FLAME YELLOW- LAZY1. Low gas pressure1. Check with gas utility company
2. Flue clogged2. Clean, locate source and correct
3. Main bumer line clogged3. Clean, locate source and correct
4. Obstruction in main burner orifice4. Clean or replace orifice
PILOT WILL NOT LIGHT OR REMAIN LIT1. Air in gas line1. Bleed the air from the gas line
2. No gas2. Check with gas utility company
3. Dirt in gas lines3. Notify utility-install sediment trap (dirt leg) in gas line
4. Pilot line or orifice clogged4. Clean, locate source and correct
5. Defective thermopile5. Replace thermopile
6. Cold drafts6. Locate source and correct
7. Gas control/thermostat ECO switch open7. Replace gas control/thermostat
8. Defective igniter or electrode8. Replace igniter or pilot assembly
9. Low gas pressure9. Check with gas utility company
HIGH OPERATION COSTS1. Thermostat set too high1. Set temperature dial to lower setting
2. Sediment or lime in tank2. Drain/Flush-Provide water treatment if needed
3. Water heater too small for job3. Install adequate size heater
4. Wrong piping connections4. Correct piping-dip tube must be in cold inlet
5. Leaking faucets5. Repair faucets
6. Gas leaks6. Check with utility-repair at once
7. Wasted hot water7. Advise customer
8. Long runs of exposed piping8. Insulate piping
9. Hot water piping in exposed wall9. Insulate piping
10. Leaks or cracks in dip tube10. Check dip tube. Replace if faulty
PILOT FLAME TOO SMALL1. Pilot line or orifice clogged1. Clean, locate source and correct
2. Low gas pressure2. Check with gas utility company
3. Defective pilot3. Replace pilot
INSUFFICIENT HOT WATER1. Thermostat set too low1. Turn temperature dial to desired setting
2. Sediment or lime in tank2. Drain/flush-provide water treatment if needed
3. Water heater too small3. Install adequate size heater
4. Wrong piping connections4. Correct piping-dip tube must be in cold inlet
5. Leaking faucets5. Repair faucets
6. Wasted hot water6. Advise customer
7. Long runs of exposed piping7. Insulate piping
8. Hot water piping in outside wall8. Insulate piping
9. Low gas pressure9. Check with gas utility company
SLOW HOT WATER RECOV- ERY1. Insufficient secondary air1. Provide ventilation to water heater. Check flue way, flue baffle and burner
2. Flue clogged2. Clean flue, locate source and correct
3. Low gas pressure3. Check with gas utility company
4. Improper calibration4. Replace gas control/thermostat
5. Gas control/thermostat set too low5. Turn temperature dial to desired setting
6. Water heater too small6. Install adequate size heater
7. Wrong piping connections7. Correct piping-dip tube must be in cold inlet
8. Wasted hot water8. Advise customer
DRIP FROM RELIEF VALVE1. Excessive water pressure1. Use a pressure reducing valve and relief valve
2. Heater stacking2. Lower the thermostat setting
3. Closed water system3. See “Closed System/Thermal Expansion"
4. Temperature setting too high4. Decrease the temperature setting
THERMOSTAT FAILS TO SHUT OFF1. Defective gas control/thermostat1. Replace gas control/thermostat
2. Improper calibration2. Replace gas control/thermostat
COMBUSTION ODORS1. Insufficient secondary air1. Provide ventilation to water heater. Check flue way, flue baffle, burner
2. Flue clogged2. Clean, locate source and correct
3. Heater installed in a confined area3. Provide fresh air ventilation
SMOKING AND CARBON FORMATION (SOOTING)1. Insufficient secondary air1. Provide ventilation to water heater. Check flue way, flue baffle, burner
2. Low gas pressure2. Check with gas utility company
3. Flue clogged3. Clean, locate source and correct
4. Defective gas control/thermostat4. Replace gas control/thermostat
5. Heater installed in a confined area5. Provide fresh air ventilation
6. Burner flame yellow-lazy6. See “Burner Flame Yellow-Lazy"
CONDENSATION1. Temperature setting too low1. Increase the temperature setting
2. Water heater too small2. Install adequate size heater
BURNER FLAME FLOATS AND LIFTS OFF PORTS1. Orifice too large1. Replace with connect orifice
2. High gas pressure2. Check with gas utility company
3. Flue clogged3. Clean flue and burner-locate source & correct
4. Cold drafts4. Locate source and correct
BURNER FLAME TOO HIGH1. Orifice too large1. Replace with connect orifice
FLAME BURNS AT ORIFICE1. Defective gas control/thermostat1. Replace gas control/thermostat
2. Low gas pressure2. Check with gas utility company
3. Orifice not properly installed3. Reinstall the orifice

John Wood JW375T75N-AV water heater troubleshooting

ProblemCauseSolution
WATER LEAKSImproperly sealed, hot or cold supply connection, relief valve, drain valve, or thermostat threads.Tighten threaded connections.
Leakage from other appliances or water lines.Inspect other appliances near water heater.
Condensation of flue products.Refer to CONDENSATION.
LEAKING T&P VALVEThermal expansion in closed water system.Install thermal expansion tank (DO NOT plug T&P valve).
Improperly seated valve.Check relief valve for proper operation (DO NOT plug T&P valve).
SMELLY WATERHigh sulfate or mineral content in water supply.Drain and flush heater thoroughly, then refill.
Bacteria in water supply.Chlorinate or aerate water supply.
PILOT WILL NOT LIGHTGas control knob not positioned correctly.Refer to LIGHTING INSTRUCTIONS.
Main gas supply off.Turn on main gas shutoff valve.
Thermocouple malfunction.Replace pilot assembly and/or thermocouple.
Match not close to pilotLocate pilot, move match doser.
BURNER WILL NOT STAY LITThermocouple malfunction.Replace pilot assembly and/or thermocouple.
Defective Gas Control.Replace Gas Control.
PILOT OUTAGEDirty pilot burner.Clean pilot assembly.
Thermocouple malfunction.Replace pilot assembly and/or thermocouple.
Defective Gas Control.Replace Gas Control.
Thermocouple tip is not in contact with pilot flame.Insert thermocouple correсtly.
NOT ENOUGH HOT WATERHeater not lit or thermostat not on.Refer to LIGHTING INSTRUCTIONS.
Thermostat set too low.Refer to TEMPERATURE REGULATION.
Heater undersized.Reduce hot water use.
Low gas pressure.Contad your gas supplier.
Incoming water is unusually cold.Allow more time for heater to re-heat.
Leaking hot water pipes or fixtures.Have plumber check and repair leaks.
High temperature limit switch activated.Contact a service agency to determine cause.
WATER TOO HOTThermostat set too high.Refer to TEMPERATURE REGULATION.
WATER HEATER SOUNDSCondensation dripping on bumer.Refer to CONDENSATION.
SIZZLING OR RUMBLINGSediment or calcium in bottom of heater tank.Clean sediment from tank. Refer to DRAINING instructions in Maintenance section of manual.
SOOTINGImproper combustion.No adjustment available. Contad a service agency to determine cause.
VENT GAS ODORSLack of supply air.Contact a service agency to determine cause.
Improperly installed vent piping.
Downdraft.
Poor combustion.

John Wood POWER VENTED GAS FIRED water heater troubleshooting

PROBLEMPOSSIBLE CAUSE(S)CORRECTIVE ACTION
BURNER FLAME TOO HIGH1. Air inlets blocked1. Unblock inlet air openings
2. Insufficient secondary air2. Provide ventilation to water heater
3. Orifice too large3. Replace with correct orifice
FLAME BURNS AT ORIFICE1. Low gas pressure1. Check with gas utility company
2. Defective gas control valve/thermostat2. Replace gas control valve/thermostat
INSUFFICIENT HOT WATER1. Low gas pressure1. Check with gas utility company
2. Orifice too small2. Replace with correct orifice
3. Thermostat set too low3. Turn temperature knob to higher setting
4. Gas control error codes4. Refer to gas control error codes
5. Sediment or lime in tank5. Drain/flush-provide water treatment if needed
6. Water heater too small6. Install adequate heater
7. Wrong piping connections7. Correct piping: dip tube must be in cold inlet
8. Leaking faucets8. Repair faucets
9. Wasted hot water9. Advise customer
10.Long runs of exposed piping10.lnsulate piping
11 .Hot-water piping in outside wall11 .Insulate piping
WATER IS TOO HOT1. Thermostat is too high1. Turn temperature knob to lower setting
2. Defective gas control valve/thermostat2. Replace the gas control valve/thermostat
SLOW HOT WATER RECOVERY1. Insufficient secondary air1. Provide ventilation to water heater. Check flue way. flue baffle and burner
2. Low gas pressure2. Check with gas utility company
3. Orifice too small3. Replace with correct orifice
4. Thermostat set too low4. Turn temperature knob to higher setting
5. Heater too small5. Install adequate heater
6. Wrong piping connection6. Correct piping-dip tube must be in cold inlet
7. Wasted hot water7. Advise customer
8. Flue clogged8. Clean flue, locate source and correct
9. Air inlets blocked9. Unblock inlet air openings
DRIP FROM RELIEF VALVE1. Pressure build-up1. Use a pressure-reducing valve and relief valve
2. Heater stacking2. Lower the thermostat setting
3. Closed water system3. See thermal expansion section
4. Improperly seated valve4. Check Relief valve for proper operation (Do Not plug T&P valve)
GAS CONTROL VALVE/ THERMOSTAT FAILS TO SHUT OFF1. Defective gas control valve/thermostat1. Replace gas control valve/thermostat
SMELLY WATER1. Sulfides in water supply1. Chlorination procedure
2. Bacteria in water supply2. Chlorination procedure
3. Standard anode incompatible with water composition3. Install special annode
CONDENSATION1. Filling the new water heater for the first time1. Normal operation: the condensation should disappear after heater warms up
2. Moisture from the products of combustion2. Normal operation: the condensation should disappear in time
3. Water dripping from blower assembly3. Install condensate hose to drain port on the rubber coupling
4. Undersized water heater4. Install adequate heater
COMBUSTION ODOURS1. Air inlets blocked1. Unblock inlet air openins
2. Insufficient secondary air2. Provide fresh air ventilation to the water heater
3. Flue clogged3. Clean, locate source and correct
4. Heater installed in a confined area4. Provide fresh air ventilation to the water heater
5. House too tight5. Provide fresh air ventilation to the water heater
SMOKING AND CARBON FORMATION1. Air inlets blocked1. Unblock inlet air openings
2. Insufficient secondary air2. Provide ventilation to water heater. Check flue way. flue baffle and burner
3. Low gas pressure3. Check with gas utility company
4. Orifice too large4. Replace with correct orifice
5. Flue clogged5. Clean, locate source and correct
6. defective gas control valve/thermostat6. Replace gas control valve/thermostat
7. Heater installed in a confined area7. Provide fresh air ventilation
UNABLE TO LIGHT THE BURNER1. Air in gas line1. Purge the air from gas line
2. Pressure switch2. Check the pressure switch, make sure the pressure switch hose is not kinked
3. Blocked exhaust3. Check vent pipe for blockage
4. Wire connection4. Check wire connections
5. Defective gas control valve/thermostat5. Replace the gas control valve/thermostat
6. Defective igniter6. Replace igniter
SIZZLING, RUMBLING NOISE1. Scale and sediment1. Drain/flush-provide water treatment if needed
2. Condensation dripping on burner2. Refer to “Condensate" section
WATER LEAKAGE1. Condensation1. Refer to “Condensate" section
2. Dripping Temperature & Pressure Relief Valve2. Refer to “Temperature & Pressure Relief Valve" section
3. Thermostat does not shut-off3. Check the Thermostat
4. Drain valve dripping/leaking4. Back flush to clean- out sediment, replace if necessary.
5. Tank Leak5. Check “Leakage Checkpoints’
BLOWER WILL NOT START1. No power to unit1. Plug in power cord, check fuses and/or supply voltage
2. Thermostat set too low2. Turn temperature knob to higher setting
3. Defective air pressure switch3. Replace air pressure switch
4. Defective blower4. Replace blower
5. Disconnected or loose wire5. Repair and reconnect wires
6. Control locked out6. Reset - determine cause of lockout
7. Incorrect polarity7. Repair polarity
BLOWER RUNS CONTINUOUSLY1. Air pressure switch not closing due to insufficient draft - check for:1. Determine cause of insufficient draft. Check draft with manometer at pressure switch
a. Vent piping blockeda. Remove blockage
b. Piping length too longb. Reduce vent length/increase vent size
c. Clogged/dirty blowerc. Clean blower wheel
2. Disconnected, tom or blocked pressure switch hose from air pressure switch to blower housing2. Reconnect or replace pressure switch hose
3. Defective pressure switch3. Replace defective pressure switch
4. High limit switch open due to excessive vent temperature or defective switch4. Determine cause of overheating check for: overfiring, insufficient air supply, high ambient air temperature (once high limit switch activated, must be replaced)