Draining an Immersion Heater

What You'll Need
Immersion Heater
Hot water Supply

If you have an immersion heater in your home, you may need to drain it from time to time in order to maintain the heater and check for faults. Immersion heaters are made from a wide variety of materials, including copper, steel and iron, and they may also come with a range of basic controls that allow you to determine what goes on inside the heater. This can be very useful when you are trying to drain the heater, as you will need to know exactly what is going on. Draining your immersion heater is not a difficult task, and you should be able to manage it by yourself without professional help.

Step 1 - Turn off the Power

In order to drain your immersion heater, you will need to make sure that it doesn't start producing more hot water while you are draining it. This can be solved by simply turning off the heater, and then removing it from the electrical supply. You should also shut off the mains water, as this can sometimes drip water into the heater even when the power is not on. Use a wrench to shut off the mains, and allow the heater to cool before touching.

Step 2 - Begin Draining

Look at your immersion heater. At the bottom of the heater, you should be able to locate a little switch, known as the drain valve. You should run a nearby tap until all of the hot water is gone from the system. You should open up the drain valve on the heater, and allow the little bit of water at the bottom to run off into a bucket or other suitable container. This should completely drain the immersion heater.

Step 3 - Stop Draining

It may take quite a while for the immersion heater to be completely drained. You can then carry on with the tasks which you wanted to perform. Once you have completed the maintenance, you can then close up the access panel on the immersion heater, and prepare to fill it with water. Only allow the immersion heater to start filing with water once the access panel has been replaced, and all of the different screws have been put back in the right places. If you let water run into the heater before the screws have been replaced, you could end up with a leak.

Step 4 - Restore the Immersion Heater

Once you are done, you can then shut off the drain valve, and turn the mains water back on. The water will flow into the immersion heater, and start filling it up. You should wait until the heater is completely full with water before you plug the heater back into the power supply, and turn on the electricity again. You should then run a sequence of the heater to check that it is working thoroughly. Drain the water from the bucket into a nearby sink.