Water Heater Repair


Water heater repair can either involve a simple fix or a massive intervention, and sometimes the loudest symptoms of trouble can mean the smallest of repairs. Whether or not you take on the repair of your water heater could depend on what type of heater that you have as well.

Here are a few tips for repairing your hot water heater, starting with troubleshooting advice for gas heaters, moving onto electric heaters, and finally touching on the ever-more-popular tankless heaters.
You can also read our information on water heater problems if you need more help.

Repairing Gas Heaters

The most common tools that you will need to repair your gas heater are a pipe wrench, other open-ended wrenches, thin copper wire, plumber’s pipe tape, a vacuum cleaner and a soft brush. If you are not handy with these tools, then you might need to call in a plumber (Check HERE for free quotes). But if you do want to repair your gas water heater yourself, then please read on.

  • A common problem with gas heaters is the lack of a pilot light. If you have a pilot that is out or goes out frequently, you should first try to re-light the pilot. If it goes out again soon after, clean the pilot orifice, tighten the thermocouple connections and/or replace the faulty thermocouple.
    Instructions for re-lighting should be on the panel. You should always turn the gas control knob to “off” and wait several minutes for all gas to clear. If your pilot does not light at all, you should probably call the gas company.
    This is a fairly easy repair activity, but it might involve a lot of bending down and stretching. The pilot light may be hard to reach.
    Read the instructions in the manual that came with your heater and follow them to the letter. You don’t want to play around with natural gas.
  • Another quick fix for a minor problem could be re-setting the temperature control on your heater. If your water is actually too hot, you might need a repair or replacement of your thermostat. A pro will have to get involved there with a gas heater.
  • If you have a leaky heater, you could need to replace the pressure relief valve or the drain valve. If you are to replace either valve, do so after turning off the heat and letting the water cool down. You will get a little spray when you replace these valves; it’s best if that spray is not scalding.
  • If you find evidence of widespread rust, there’s not much that you can do other than replace the heater entirely.
  • A noisy heater could be the result of too much sediment built up inside. For this problem, try draining and flushing the tank, then re-filling it. This can also cure a dirty water problem at times. Such draining of your tank will prolong its life and should be part of your regular maintenance. You can find detailed instructions on how to drain and re-fill your tank here.
    If you live in an area with hard water, you can lessen the build-up of sediment by lowering your water temperature to 130° F.
  • Another easy fix for subpar performance is replacement of the anode rod in your tank.

As you work on your gas heater, be aware of possible gas odors.
If you smell too much gas, close the gas shutoff valve and ventilate the room quickly. You might have a gas leak and that is going to be beyond your expertise to repair.

Repairing Electric Heaters

Fortunately, electric heaters are less complex than gas heaters. The first step to remember before fiddling around with your electric heater is to turn off the power supply to your heater by flipping the switch off in your circuit box.

  • As part of your regular maintenance, check the anode rod in your tank once a year.
  • A noisy electric heater is not much different than a noisy gas heater. You probably need to get rid of the sediment by draining and re-filling the tank.
  • Again, widespread rust cannot be cured. You will need a new apparatus.
  • It is easier to get at a thermostat in an electric water heater, so some DIYers tackle this problem themselves. If you unscrew and remove the access panel, you can test the thermostat by lowering and raising the temperature as you turn its dial. If the heater does not maintain that temperature after you restore power, your thermostat will need to be repaired or replaced, which is not too difficult.
  • If the thermostat is not the problem, the heating element might be. You can also get a look at it as you disassemble the access panel. Take the old part in when you seek a replacement so that you can be sure that they match.

Repairing Tankless Heaters

About the only step that an amateur can take in repairing a tankless heater is to replace the heating element.

  • As with other types of heaters, turn off the power supply. Turn on the hot water where the tankless heater serves to get the water out of the line, and remove the screws on the heating chamber plate to drain the water into a bucket.
  • Remove the screws at the top of the element to free the red and black wires from the heating element, then disconnect the element.
  • If the element needs replacing, make sure the O-ring seal is secure and install the new assembly into the heater. Make sure that the control board is dry. Use a hair dryer to help with this if necessary. It cannot become wet as you do your repair work. Check the circuit with a volt meter.

Again, if you need more information you can also try our problem infopages.