Creating a Beautiful Outdoor Space

Why The Water In Your Gas Water Heater Isn't Hot And How To Fix It

20 November 2018 by Delores Chavez

If you were the first in your household to shower this morning and ended up with only lukewarm water coming out of the hot water tap, then your home's gas water heater may need some attention. Thankfully, there are only a few things that cause this issue and they are all easy to fix.

Below is everything you need to know to figure out why your water heater isn't performing as designed, as well as how to get the problem fixed.

Issue #1: There Is No Hot Water at All

If your water heater isn't producing any hot water at all, then it is possible the pilot light has gone out. Since checking the pilot light is simple, you should always do this before looking for another issue with any gas appliance.

If you discover the pilot light's flame has gone out, then you should either re-light it or call your gas provider and have them come to your home and do it for you.

If you discover the water heater's pilot light is burning just fine, then it is more than likely the water heater's burner or thermostat has failed or is malfunctioning.

Since replacing these parts can be a bit complicated for someone without experience with gas appliance repair, you should have a licensed plumber come to replace them.

Issue #2: The Hot Water Isn't Always the Same Temperature

If your water is lukewarm only first thing in the morning or when no one has run any hot water for a few hours, but it produces hot water other times of the day, then your water heater's thermostat may not be set correctly.

To troubleshoot the thermostat, first, check to see what temperature it is set at. If the water heater is located in your garage where someone may have bumped against it, then it may just need to be reset back to its normal operating temperature—typically 120 degrees.

If the thermostat is set on 120 degrees and you are getting hot water later in the day, then it is more than likely the thermostat is working correctly. However, the reason your morning shower was cold is that the water sitting in the tank was cooling off and the thermostat didn't hit its lower threshold to turn on the burner to reheat the water.

Since the lower threshold can be twenty or thirty degrees colder than the water the heater typically produces, this can make the water feel cold. As soon as someone uses some hot water and the cold water backfills the tank, the thermostat comes into contact with it and fires the burner. After this happens, then the water is hot again. This isn't a sign of a malfunction, but rather an interesting quirk of gas water heaters.

The best workaround is to run some hot water a few minutes before you want to shower and that will ensure the burner has just heated the water inside of the holding tank.

If neither of these issues is the problem, then it's time to contact a water heater repair technician. 

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