Water Heater Troubleshooting | Possible Causes & Fixes



Nobody wants to run out of hot water, especially during the winter. While a water leak cries for professional help and a gas leak calls for immediate evacuation and help from the utility company, there is still a lot you can do to troubleshoot and fix your water heater in times of trouble.

Water heaters are used every day for bathing, washing dishes, laundry, and more. When it doesn’t produce any heat, it can be a serious problem and inconvenience.

Warning: If you ever smell gas (sulfuric, rotten-egg-like smell), evacuate the entire household immediately and call your gas company or fire department.

No Hot Water

Temperature Control – Turn the temperature up; we recommend around 120-130 degrees. If the temperature control or thermostat is defective, contact a professional to replace the thermostat assembly.

Pilot Light Out – Relight the pilot. Follow the instructions located on the tank and be careful. Make sure there is no built-up gas by turning off the off line and waiting around 10 minutes for all gas to dissipate.

Thermocouple – If the thermocouple (the piece that shuts off gas flow if there is not enough heat) is defective, it may shut off gas flow permanently. Contact a professional for replacement.

Check for Power – If the water heater is not receiving power, check the water heater master switch and circuit breaker/fuse box.

Tripped Temperature Cutoff – Remove the access panel and press the reset button.

Sometimes, if the burner won’t light or there is a defective heating element, you will need to replace the element (maybe both elements). This repair or replacement is best left to the professionals.

Too Little Water or Not Enough Heat

Temperature Control – Turn the temperature up; we recommend around 120-130 degrees. If the temperature control or thermostat is defective, contact a professional to replace the thermostat assembly.

Partly Closed Gas Line – Make sure the gas valve is fully open. Turn the gas line handle completely parallel to the gas pipe to open it up (turn the handle perpendicular to the pipe to shut off gas flow).

Pilot/Burner Flame Not Blue – Just like your furnace flame, your water heater flame should be blue. Any other color than blue indicates a combustion hazard. If it is not blue, do not attempt to fix the flame color on your own. Contact a professional.

Clogged Burners – If your burner ports are clogged, you may be able to clean them with an old toothbrush. Just make sure you follow instructions exactly and turn off the gas supply line before proceeding. Contact a professional if you have any doubts.

Low Voltage – Contact your utility company

Again, the cause may be a defective heating assembly. If this is the case, contact a professional for replacement.

Water Is Too Hot

Temperature Control – Turn the temperature down; we recommend around 120-130 degrees. If the temperature control or thermostat is defective, contact a professional to replace the thermostat assembly. 140 degrees is normally too hot for everyday use and for households with young children.

Blocked Flue – Make sure the flue is not blocked. Turn off your water heater and clear the flue obstruction before restarting the water heater.

Defective Hot-Temperature Cutoff or Heating Assembly – Contact a professional to replace these defective parts.

Noises (Banging, Rumbling, Whistling, Etc.)

Rumbling (Overheating) – Put on a work glove and try opening the temperature-pressure relief valve located on the top of the water heater. If steam or boiling water escapes, shut down the water heater immediately and contact a professional.

Whistling/Sizzling/Rumbling (Sediment Buildup) – With time, sediment and minerals gather at the bottom of the tank. Periodically draining and flushing the tank can prevent this problem. Contact a professional to make sure. You may also need to replace the heating elements.

Whistling/Popping (Burner Assembly) – If your burner is misadjusted or not working, contact a professional for adjustment, repair or replacement.

Water is Leaking

If you notice water buildup or a water leak around your water heater, check the following:

Leaking Drain Valve – Simply tighten the valve by hand (be careful not to overtighten it). If the drain valve is defective, replacing the valve washer may fix it. If not, contact a professional.

Open Temperature-Pressure Relief Valve – Check the temperature-pressure relief valve at the top of the tank and make sure it is closed. If defective, contact a professional.

Old, Corroded Tank – This is extremely dangerous. If you notice corrosion on your tank, don’t wait for massive water damage to make a move. Contact a professional right away for a full replacement. To be safe, you may want to turn off the water supply and drain the tank while you wait for replacement.

Leaking Heating Elements – If water is leaking from your heating elements, contact a professional right away. You may need to replace the heating elements, tighten mounting bolts, or replace gaskets. Do not attempt this on your own!

If you’re experiencing insufficient or no hot water in your Northern California home, contact Service Champions today. We have years of experience working with all types of water heaters and can get the hot water flowing back into your home.

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