Water heater research

How to Stop A Water Heater Overheating

(Last Updated On: April 12, 2020)

Considering how important hot water is to our modern lives, it is quite surprising how few people actually spend any time thinking about their water heater in their home–until something goes wrong!

We require hot water for so many different purposes, including taking baths and showers, washing our clothes and using the dishwasher, however we devote very little effort into thinking about how our water heater actually works and whether or not the system is experiencing any issues, until we absolutely need to. 

Even people who seem to take great care over their property’s maintenance often only consider addressing issues regarding their water supply and water temperature once a problem has become apparent. It’s a dangerous problem, because with this lack of due care and attention an overheating or malfunctioning water heater can be potentially very dangerous to you and your possessions. 

Here, we look at some of the best courses of action to take to stop your water heater from overheating in the first place, and to address problems when they arise. 


If you suspect you have an overheating problem:

Look At Your Temperature Settings

Best Gas Tankless Water Heater

Although it may seem obvious, many people are still unaware that often your water will be too hot because your water heater’s thermostat has wrongly adjusted by accident. Water heating systems have many differences depending on which manufacturer produced them and although some brands do have safety latches which can prevent this from happening, many others have no such safety measures in place.

Generally, if your thermostat is set somewhere between 110 and 125 degrees, your system will be running at the optimal temperature to produce hot water for most purposes. Some systems, however, are capable of going a lot higher than this level and therefore if your water is suddenly excessively hot, you should first check your thermostat’s temperature settings before you leap to any other conclusions.

Mechanical Faults Of The Thermostat Or Elements

If you have already checked your water heater’s thermostat and discovered that it is set correctly but your water is still too hot, a mechanical fault must be the problem. Getting your system regularly maintained by a professional is the best way to prevent problems like this from occurring, and how often these check ups should take place will depend upon how old and how reliable your system is.

Usually, the most common reason for an overheating water heater is damage to the elements or a malfunctioning thermostat. Over time, elements collect sediment and become calcified. If they are not cleaned from this build up or replaced should the need arise, the elements will have to work a lot harder in order to warm the water and eventually they will inevitably break. This will result in your water suddenly becoming extremely hot before your element completely breaks.

You can prevent this from happening easily by simply checking your elements every year and cleaning away any residue and sediment.

Most thermostat issues are a result of everyday wear and tear. Although the average thermostat should have a long lifespan, eventually their cycle system wears out and this leads to the thermostat telling the elements to heat up the water continuously even though the set temperature has already been reached. Until it is turned off or replaced, the water will continue to overheat considerably.

To make sure things don’t go south:

Clean And Decalcify

The best thing you can do to prevent issues in your tankless water heater is to be sure to decalcify and descale the innards regularly. Your manual will tell you how often to do so, and what products to use. Be sure to stick to the schedule, and adjust according to your water composition. The vast majority of issues with these appliances can be avoided by doing this religiously!

Check Temperature And Pressure Release Valves

checking temperature and pressure release valves

If you ensure that regular checks to your temperature and pressure release valves are carried out you can cut out a lot of the risk factors and damage which could potentially occur inside your water heater. If these valves fail, you can have catastrophic consequences as the water will heat continuously and the pressure inside the system will continue to rise. Eventually, this could possibly lead to an explosion which would clearly be a disaster.

The good news is that it is very simple for householders to ensure that their discharge pipe system is frequently cleared out as this is usually the main cause of the temperature and pressure release valves failing. You can accomplish this by just lifting up the supply lever for one or two seconds to enable the water to flush the valve. If the pipe is cleared swiftly and smoothly you have nothing to be concerned about however if you see visible residue or if drainage takes a lot longer than you would normally expect, you should call a plumber to come out and take a look at your hot water system.

Modern hot water heaters are very well designed and are very high quality so if you care for them properly they should enjoy a long useful lifespan. This holds true for all types of hot water heater on the market today including the electric, gas powered and even the new solar powered models which are becoming a lot more popular these days. However, it is important to note that even the best and most expensive model of water heater will not maintain itself. Even a top quality water heater will break down eventually if it is not looked after properly or subjected to annual maintenance and check ups.

The good news is that if you take the time to perform quick tests regularly you can save yourself a lot of stress and a lot of expense at a later date. As a rule of thumb you should always engage the services of a qualified plumber to carry out a full system maintenance every few years, and even more frequently if you have an old system or one that has failed on a regular basis, so that they can check that your heating unit is still functioning as it should.

However you can save money by carrying out all of the most basic tasks like clearing the elements, draining out excessive sediment from the tanks and checking your temperature settings yourself on a more frequent basis. Tankless water heaters are an even more convenient option than the traditional storage water heater since they have no tanks from which to drain sediment and therefore you are giving yourself one less task to deal with on a regular basis. Learn more when you check out our page.

Tankless Reviews was created with the goal of helping people to understand the benefits and practical knowledge related to tankless water heaters. After purchasing my very first tankless heater years back, I realised that other people needed to hear about the incredible money-saving ability of this household item, and wanted to share my lessons with you!