8 Reasons Your Water Heater Keeps Turning off – 2024 Guide

The lifetime of a boiler is 6 to 10 years, with proper maintenance. However, there are times when for some reason or other it does not turn on and that is when we do not know what to do. There is nothing worse than having to take a cold shower, because of the water heater failure.

The most common are those that run on electricity and gas. Depending on whether they are on electricity or gas, it depends on the potential causes of the problem.

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Gas water heaters


When you turn on the faucet and don’t turn on the heater there can be many reasons why this happens, we tell you the five reasons why this can happen.

The normal thing is that when you open the tap, the spark sounds and the blue flame ignites and it begins to heat, but often it happens that it does not light and there can be various problems. There are many causes as we told you, but we will address the five most common reasons why this happens.

No gas supply

According to the smartchoice.plumbing, that is the first thing you should check when it keeps turning off. Before trying to solve other problems or calling technician, check gas supply. Maybe it is that simple.


This is the most common of all, these heaters use batteries that are the ones that generate the spark and then ignite the flame when the batteries run down then don’t make the flame with replacing it should fix.

If this does not happen then the problem may be different. Read on to find out what it can be then.

Low water pressure


When there is low water pressure, then the membrane does not act and the heater does not turn on, but it may be due to a failure as it is poorly regulated or a very open flow. It can also have limestone buildup inside and may even be due to limestone buildup in hot water pipes.

Lock on control module

In automatic heaters, it also occurs that the electronic module is blocked either because it has caught moisture or because it has a component in poor condition. Sometimes by resetting it, it unlocks and continues to work as if nothing had happened.

The starting microswitch does not work

Heaters that have batteries, such as point one and its problem, is a switch that activates when the membrane opens the faucet and the switch signals the control module to turn on the heater. If it doesn’t work or it gets degraded, it may not send the order to the module and it starts to fail.

The hydro generator does not send current to the control module

When this happens it may be because the hydrogenerator does not work properly and does not send current to the control module, so the heater does not start.

Shall you call the technician?


This has no discussion, when something happens with the heater you have to call a technician since these are delicate and dangerous devices because they work with gas, the most you can do is change the batteries.

The best thing is that you always call a qualified technician who has licence in order and that offers you a guarantee, even if it is one of the same best brand, because they are people prepared to offer you a first-class service with a guarantee.

Do not try to save money by calling anyone who could damage the heater or try to save all the money by fixing it yourself. Since it can be much more expensive.

Electric water heaters


The functionality of an electric boiler is actually easy to understand. It is a kind of large thermos bottle, into which cold water is poured, which is then heated by a heating element, and which is fed into the water pipes to your hot water tap.

The walls of your electric boiler consist of several layers of insulation. This is to store heat and prevent the tub from corroding. “Aggressive water” damages the tub faster than water containing limestone and magnesium, which can, however, lead to calcification of the tub and the heating element.

Most common malfunctions which can lead to turning off

If only cold water flows from your hot water tap, or on the contrary, the water comes out of the pipe at the boil, it no longer work properly.

However, if the hot water tap stops working, if the boiler itself has a leak, or if the fuse blows, then it is due to the water pipes. You must therefore have a plumber solve the issue.

Check signal light to find out about electricity

The first and most important thing is whether the signal light on the boiler lights up when you turn it on. If the light bulb is on, it means that electricity is coming to the heater properly. Other elements in the electrical circuit are correct. At the same time, it is a sign that the heater has burned out and needs to be replaced.
In order to be 100% sure that the heater is not working anymore, it is necessary to visually inspect the installation on the heater.


Heater failure

If cold water flows from your hot water tap, the heating element has not heated the water.

Thermostat failure


The water from your electric boiler is too warm. If you turn on the hot water tap, steam will come out and will even leak water near the fuse of your boiler? This malfunction is certainly related to the thermostat. To check the thermostat, you must first remove the cover of your device. Perhaps the thermostat is just set incorrectly, you can then lower it and check it after a few hours.

If you have an older electric boiler, it may happen that the thermostat is defective. Before testing it, you must first disconnect your device from the power and disconnect the thermostat. With a multimeter in the ohmmeter setting, you can check continuity by placing the two measuring tips of the measuring device on the input contacts (for connecting the supply lines) of the thermostat.

You can now check the continuity, the contacts must be closed and the measured value should be zero. You can try heating up the thermostat rod with a lighter to see if it responds. You can try this on the two input contacts. If the thermostat does not turn off the circuit, then it will likely need to be replaced.


Our advice is to call professionals in the event of a boiler failure. It does not matter whether it works on gas or electricity, repairs are always complex and require knowledge and appropriate tools.