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Are Water Heater Thermostats Universal?

Thermostats are used in various heating and cooling devices to make sure that the temperature doesn’t go above or below a certain point.

You definitely would have noticed one on your air conditioner, refrigerator, oven, or water heater.

To put it in simple terms, a thermostat switches a device on and off when the temperature exceeds or goes below a particular point.

In this article, we are focusing on water heater thermostats and we are going to establish if they are universal or not.

Also, we will talk about how you can replace your water heater thermostat and some other things.

Water heater thermostats are not universal. Single element water heaters and dual element water heaters have some variances, and there are also differences in upper and lower thermostats in dual element water heaters. Therefore, one type of water heater thermostat cannot be interchanged for another type.

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After using your water heater for some time, it is only normal for the thermostat to begin to malfunction.

This may be due to aging, accumulation of dust, or some other causes.

When the thermostat on a water heater begins to malfunction, the safety of the users are no longer guaranteed.

However, a lot of people wonder if they can just go and buy any water heater thermostat to replace the faulty one on their device.

The answer to this question is discussed below.

Types of Water Heater Thermostat

The various types of Water Heater Thermostats are Stem Thermostats, Bulb Thermostats and Electric Thermostats.

Stem Thermostats

This type of thermostat consist of long stems which expands as the temperature of the water heater increases.

They are generally known to be affordable and reliable.

The stem thermostat however requires a high level of care when resetting it because they sometimes overheat and when this happens, it is necessary to reset the thermostat manually.

Bulb Thermostats

Bulb thermostats are also referred to as ‘capillary thermostats’.

They operate through the use of expanding liquid.

This liquid is contained in the bulb and it increases in volume, thereby, causing the heat to be produced by the heating elements.

Bulb thermostats are known to be just as reliable and precise as stem thermostats.

Electronic Thermostats

Electric Thermostats can be expensive, however, they are known to be the easiest to maintain.

They are built to be able to adjust the heat of the water whenever desired.

This is achieved through communication between the thermostat and the heating elements; the heating elements act on the directive of the thermostat.

In some cases, two electric thermostats are installed in the water tank, taking turns to heat the water.

Precautions should however be taken when using the electric thermostat by shutting down the power to the heater.

Are they Universal?

water heater with thermostats

The answer to this is ‘No’- water heater thermostats are not universal.

The implication of this is that a type of water heater thermostat cannot be interchanged for another type of water heater thermostat.

As a result, when a water heater thermostat develops a fault, it might be a futile effort getting an entirely type.

The first thing to note is that the structure which enables each to function differs and cannot be interchanged.

For example, the bulb thermostat cannot be interchanged for the electric thermostat due to its structure.

It operates through expanding liquid which is not the same with the latter and as such would not enable them to be substituted for each other in the event of a break down.

Also, some water heaters are designed to operate with only two heating elements.

As a result, a single heating element would not work with it.

For the water heater to function effectively, the required processes must be duly followed. If ignored, the water heater might not function as it should. In some cases, they don’t even function at all, therefore, the user must have a good knowledge of the water heater.

Furthermore, some water heaters require the exact model of thermostats before they can function effectively.

This means that an electrical thermostat can have various models, and some water heaters, which are designed to function with a particular model might not function effectively with another model even though they are of the same type.

Sometimes, the solution to this is to write out the model of the thermostat which is sometimes on a label fixed to the thermostat.

Another option is to consult the services of a professional technician because the services of a qualified expert would be greatly needed.

Choosing Your Water Heater Thermostat

Given the fact that there are different types of water heater thermostats and these thermostats are not universal, it is important to note certain factors before you go ahead to choose any water heater thermostat.

The following are some of the factors that you might want to put into consideration:

  • Cost

This is a very important factor to consider as there are various water heater thermostats with their prices differing from one another.

Regardless of your budget, you stand the chance of getting an efficient water heater thermostat.

  • Number of Heating Elements

Some water heater thermostats have one heating element while others have two heating elements.

A single element would not work with a double element.

Therefore, the user must be mindful of this.

  • Temperature Gauge

The temperate gauge helps to know the extent to which the water heater is hot.

It is advisable to keep this in mind because it will help to know if the water is not hot enough or if the water is too hot.

  • Additional Features

You can also consider some new features to ensure you get the best out of your water heater.

Some new designs now enable the users to connect their mobile phones to the water heater thermostat.


The fact that water heater thermostats are not universal does not actually pose a problem.

What is needed is a good knowledge of the kind of water heater you are using and its compatible water heater thermostat.

Users must therefore be meticulous in making their choices so as to get the best which they deserve.

Also, the services of a qualified technician should be employed when the situation calls for it.