Plumbing, Heating and Pool Repair Guides

AO Smith ProMax Water Heater Troubleshooting

/
/
/
1442 Views

WeT HeaD KnowledgeIf you are having issues with your A O Smith ProMax Power Vent (C3FVIR) Water Heater, than this guide will hopefully help you resolve a variety of issues that could arise with this particular unit. In these tough times I can respect that not everyone can afford to hire a technician to repair every issue with appliances and other household staples. There are a multitude of problems that can go wrong with water heaters such as: water leaks, temperature/thermostat issues, odors, blower malfunctions among many other things. While most water heater issues can be solved by the average homeowner or landlord, if you feel that you can not safely make the repair please call in a certified technician.

PROBLEM: Not enough hot water.

SOLUTION: If there is not enough hot water first check to see that the switch is turned to the “ON” position and that the blower is plugged into a 115 VAC electrical outlet. If this does not work, the problem might be with the electrical outlet which will need to be repaired. If there are thermostat problems you might need to replace the thermostat. If the control harness is working improperly, try replacing it. If the high limit control circuit is open than replace the thermostat. Make sure the thermostat is not set too low, adjust the temperature setting accordingly. If the blower motor is defective than try replacing the blower assembly. Check and repair all possible leaks. Lastly, if your heater is undersized try reducing your hot water usage.

PROBLEM: Error in the Hot surface ignitor circuit.

SOLUTION: Check that all of the wiring is correct and secure. If the wiring is correct than you will most likely need to replace the hot surface ignitor.

PROBLEM: Water temperature sensor is either open or short circuited.

SOLUTION: First check that all the wiring is correct and secure. If the wiring is correct than you will probably need to replace the gas control valve.

PROBLEM: Pressure switch remained closed longer than 5 seconds after heat was requested.

SOLUTION: Check to see if the pressure switch wiring is correct and secure. If the wiring is correct than you should replace the pressure switch.

PROBLEM: Pressure switch remained open longer than 5 seconds after the combustion blower started up.

SOLUTION: Check pressure switch wiring to see if it is correct. Then check to see if the pressure switch tubing is connected properly. Check to see if air intake or exhaust is blocked.

PROBLEM: Water heater unit shuts down.

SOLUTION: Check to see if the wiring for the FV Sensor is correct. Then see if there are any open circuits to the FV Sensor. If the problem persists then replace the FV Sensor. If the Water heater locks you out after it shuts down consider cleaning and reinstalling the air intake screen on the blower assembly.

PROBLEM: Hot water or gas vent odors.

SOLUTION: Start by draining and flushing the heater and then refill it. Also make sure to chlorinate the water supply. If the problem continues it could be due to: lack of air supply, improperly installed vent piping, downdraft or poor combustion.

PROBLEM: Burner will not stay lit for more than 5 seconds.

SOLUTION: Try cleaning and reintalling the air intake screen as well as the lint screen on the blower assembly. Check to see if the flame arrestor is obstructed. Make sure the polarity on the electrical outlet that the heater is plugged into is not reversed. Also be sure that the ambient temperature in the room that the heater is in is not too high. The last thing you can try is replacing the gas valve as it may be working improperly.

PROBLEM: Water leaks.

SOLUTION: First make sure that the leak is not coming from any nearby appliances, then try tightening all threaded pipe connections. Next remove the cap on the rubber boot vent terminal of the blower assembly and install a drain tube to port as per required codes. If you have a leaking T&P valve install a thermal expansion tank and check relief valve to make sure it is operating correctly.

PROBLEM: Vent pipe is too hot.

SOLUTION: Make sure the air flow restrictor is working properly. Check to see if there is enough dilution air to mix with flue gases, also ensure that the dilution air is not too hot for mixing with flue gases.

PROBLEM: Yellow flame.

SOLUTION: Turn off the water heater and the gas and clean the burner head. Make sure there are no blockages in the air intake, exhaust ventings, and air openings in the bottom of the base pan.

14 Comments

  1. Gas Hot Water Heater will not stay lit?
    Once we have lit the pilot, after turning the thermostat up to the temprature range, burner port stays lit for just few minutes. Both the burner and pilot light go out.

    Thanks for your immediate attention!
    Guy

    • I’m having the same problems.. I have a.o. smith serial L04A143174 50gal. heater it ramdemly shuts down and restarts with a purge then restarts again then goes into lockout hope you can help with my problem

    • Gas Hot Water Heater will not stay lit?
      Once we have lit the pilot, after turning the thermostat up to the temperature range, burner port stays lit for just few minutes. Both the burner and pilot light go out.

  2. I am having a different issue. I have a A. O. Smith gas water heater FPSH-50 234 and the blower assembly is making a lot of racket and sounds like it might be going out! I can’t afford to replace it at this juncture as just the part alone is $465 + tax. That said, is there something I can lubricate inside the unit to make the noise stop? Thanks in advance for your assistance.

  3. My basement flooded and the gas value and temperature control unit were under about 15″ of water. It has been drying for two weeks now and was wondering the procedure for restart as the manual aslo got wet. Do any parts need to be replaced and which ones? Can it just be cleaned and restarted?

  4. My water heater keeps shutting down and going into vacation mode. I have tried unplugging the unit to reset it but it shuts down or stops warming water after a few minutes. Please help me! What is it with these units that everyone has major complaints about them?

  5. My A.O.Smith ProMax water heater is doing the same thing burner won’t stay lit and water heater shuts off then lockout???? What kind of crap is this!!!!

      • My water heater is doing the same thing too, the unit is stuck in Vacation mode, no hot water at all, I just checked the price of the Gas valve $437.40 , Does that price include dinner and a back rub ?, the warranty just so happened to exp. on 10-11-2012 WTF.

  6. I have a propane water heater that is 10yrs. old and has started when using the shower difficult to get water at the temperature it used to be. It takes longer to get warm water to any faucet and never gets to the original temperature. Power vent works properly and burner ignites and has blue flame but runs longer with less hot water. Digital lights appear to be correct according to owners manual. Its an AO Smith FPSH/FPCR which looks like brand new. Could you suggest where to go next.

  7. Power vent on so Smith gas hot water heater keeps running Pilot stays lit when I pull off vent pipe off power vent burner comes on and when put vent pipe back on power vent burner stops pilot stays lit

  8. Power vent on so Smith gas hot water heater keeps running Pilot stays lit when I pull off vent pipe off power vent burner comes on and when put vent pipe back on power vent burner stops pilot stays lit

Leave a Comment

Your email address will not be published.

This div height required for enabling the sticky sidebar
Ad Clicks : Ad Views : Ad Clicks : Ad Views : Ad Clicks : Ad Views : Ad Clicks : Ad Views : Ad Clicks : Ad Views : Ad Clicks : Ad Views :