Common Hot Water Heater Problems

Steps to Prevent and Service a Failed Hot Water Heater

By Mark J. Donovan




If you’ve owned a home long enough, chances are you have experienced the morning where you turn on the shower to find no hot water.

It is a frustrating experience, particularly if you step in the shower thinking the water should be warm.

Commonly the reason for a lack of hot water is a failed water heater. Water heaters fail for many reasons and always at the wrong time.

There are several common preventive measures you can take with your water heater however, to prevent a failed water heater and a subsequent loss of hot water.

In some cases you can perform your own preventative maintenance and other times you may need to call a heating service provider or plumber.

There are also several other common water heater problems that can also cause a reduction or an increase in the hot water temperature.

Hot Water Heater Pilot Light is Out

One of the most common water heater problems is a pilot light that has gone out and will not relight, or the electrical igniter will not fire.

Check to make sure that there is gas or oil in the tank and that the fuel valve to the water heater has not been inadvertently turned off.

If you are convinced fuel is getting to the water heater, then you will probably need to call a heating repair service to change out the thermocouple or electrical igniter.

Hot Water Heater Thermocouple or Electrical Igniter Failing

Thermocouples and electrical igniters frequently fail if they are old and exposed to dust and dirty oil.

If you have an electric water heater the heating coil itself frequently burns out due to corrosion that occurs inside the water tank. Usually a heating repair service or plumber can quickly replace the heating coil element.

If your hot water is either too hot or cold chances are the water heater’s thermostat has either been inadvertently adjusted, failed, or has been damaged. If appears the thermostat has been inadvertently adjusted, try adjusting it yourself and see if the water warms to your preferred level. Another possibility is that the water heater flue is partially blocked and not allowing proper air flow.

This could cause an uneven burn of the fuel which could lead to a dangerous situation as well as an improper hot water temperature.

Chimney Flue is Clogged

Make sure that the flue is free from any type of obstruction.

If the thermostat setting was not inadvertently adjusted and you have confirmed that the flue is clear from obstructions, then again it is best to call a heating repair service or plumber to replace the water heater thermostat.

Replacing a Hot Water Heater

Failed Pressure Relief Valve

Another common water heater problem is a failed pressure relief valve. This could manifest itself as a small leak or as a gushing leak. If it is a gushing leak you will certainly experience a lack of hot water.

If it is a small leak, you may find a water puddle forming in the area of the water heater. If the water heater pressure relief valve leaks it has probably done so for a good reason. Its purpose is to assure the water heater tank does not get over pressurized and explode. When a water heater pressure relief valve has fired, or begun to leak, it must be replaced as it will typically never re-seat itself fully. Again, call a heating repair service or plumber to fix it. Alternatively see how you can replace the pressure relief valve.

Water Heater is Corroded

If your water heater is making odd noises chances are there is sediment building up in the tank due to corrosion or the heating element is failing. Draining the tank can sometimes cure the problem. Other times, however, it is a sign that water heater element or the water heater itself has reached the end of its life. Water heaters typically have a short lifespan of 5-10 years.


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