My Gas Water Heater Keeps Shutting Off

2017 Jun 13
Posted in: Plumbing

If you have a gas water heater that keeps shutting off, you most likely have one of these 4 issues:

  • Dirty pilot light
  • Faulty thermopile
  • Bad gas valve
  • Dirty or clogged air inlet

 
Unfortunately, you’ll need a professional to fix any of these problems. But we’ll explain how each of these problems can cause your water heater to shut off frequently. 
 
Important note: If there is a strong smell of natural gas coming from your water heater, leave your home and call a professional immediately to avoid a natural gas explosion.
 
Need a professional now? Just contact us and we’ll send one over right away.

Problem #1: Dirty pilot burner

Your water heater’s pilot light controls when the gas burners inside the heater come on. Here’s how the process works:

  1. Gas is sent to the pilot light via your main gas valve
  2. The pilot light lights up
  3. Once the pilot light is on, the thermopile activates the main gas burners to heat your water

 
So, as long as the pilot light lights, you’ll get hot water.
 
Over time, though, the tip of the pilot burner (called the “orifice”) can become clogged with soot and other debris. And when this happens, enough gas can’t get through the orifice to create a steady flame.
 
A dirty pilot burner is most likely your problem if you see a weak, flickering yellow flame coming from your pilot burner instead of a strong, blue flame that stands at a max of ½ inch high.

What to do: 

Have a professional clean your pilot burner and inspect it for signs of damage.

Problem #2: A faulty thermopile

Your thermopile is a straight metal rod that sits next to your pilot burner and activates the gas controls of your water heater.
 
How? 
 
Well, it’s designed to turn the heat from your pilot light into electrical energy. Once the pilot light’s flame heats the thermopile to a certain point, the thermopile creates enough electrical energy to power the electronics inside the gas controls.
 
Sometimes, though, if the thermopile is dirty or needs to be replaced, it won’t be able to generate enough electrical power to activate the gas controls even if the pilot light is lit (translation: no hot water).

What to do: 

Have a professional inspect your thermopile to decide whether it simply needs to be cleaned or if it needs to be completely replaced.

Problem #3: A bad gas valve

Your gas valve is what delivers natural gas directly to your water heater. Gas from this valve lights your pilot light and eventually lights the gas burners that heat your water. But if this valve or its inner elements are damaged, it can’t deliver enough gas to your water heater, causing it to shut on and off. 
 
If you’ve ruled out problems with your pilot light or thermocouple, your water heater’s gas valve is most likely to blame.

What to do: 

Have a professional replace your gas valve.

Problem #4: Dirty or clogged air inlet

Today’s gas water heaters have air inlet screens at the bottom of the water heater that can get clogged with dust, dirt, soot, cat hair, lint, etc. And if that screen is clogged, it doesn’t let in enough air to keep the gas burners burning.

What to do: 

Have a professional inspect and clean your dirty air inlet screen.

Get help from an Arizona plumber

If you’re still struggling with a water heater that keeps shutting off, we can help.
 
Just contact us and we’ll send over an experienced plumber who can diagnose and repair your water heater.

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