What causes hot water to stop working?

We don’t realise how reliant we are on hot water until it stops working. It impacts our cooking, cleaning and hygiene, especially during periods of low temperature where we spend more time indoors. Understanding what can cause a loss of hot water is essential to helping the problem get resolved quickly, with the right part able to be sourced and fitted as needed. In this blog, you’ll find the most common factors that lead to hot water not working in your home.

Why is my central heating working but the hot water isn’t?

Many modern boiler systems are combi boilers that can provide both hot water and central heating. This leads many people to believe that an issue with their boiler will affect heating for both equally. However, combi boilers heat and divert hot water as it is needed for the purposes of both central heating and hot water outlets. This means it is connected to both radiators and taps in the property. There can therefore be issues which are isolated to either of these.

Combi boilers use condensing technology that allows for more efficient heating by harnessing latent heat that resides in flue gases. This is a natural by-product of gas burner heating, which is then ‘recycled’ to decrease the amount of fuel used by the boiler. This is important for these systems as they function as a hot water boiler and a central heating boiler.

Common causes for a loss of hot water

There are a variety of factors and developments that can lead to a loss of hot water within your home. While certain problems are more likely depending on the make, model, and the building being supplied, the list below is designed to offer an overview of what can cause loss of heating for hot water.

Sometimes, if the boiler is set at a temperature that’s lower than the ambient temperature in the property it won’t come on at all. Similarly, if your boiler has a timer, it’s worth checking that it hasn’t been adjusted by accident. Power cuts can cause boilers to be reset, meaning any existing settings previously inputted will be lost. This may also mean that it takes a little longer for the unit to provide hot water after the power has been restored.

The boiler diverter valve is a part responsible for allocating heat between radiators and hot water for use in taps. If it gets stuck and is unable to open and close properly, this will lead to either a loss of central heating or hot water while the other remains on. Sourcing a replacement diverter valve, or other important component, is an effective solution to restore hot water.

Most boilers are required to operate at a water pressure of between 1-1.5 bar, although this can vary between makes. Anywhere below the recommended boiler pressure can lead to the hot water not working in the property.

Cold weather can cause boiler pipes to freeze, particularly the condensate pipe. This causes a blockage which prevents water from re-entering the unit for heating. Modern boilers will typically display an error code in the event of a frozen pipe, which makes it far easier to diagnose the problem.

If other household appliances are working as they should, it could be the case that a fuse has blown, or a switch has been tripped. This can be confirmed by checking the fuse box, after which you should go through the process of resetting the boiler that’s outlined in the manual.

Market leaders in boiler spares and parts

Our primary goal at National Boiler Spares is to ensure that no one is left without hot water or central heating for long. It doesn’t seem like much, but we know just how impactful it can be to your quality of life when either of these stops working. To this end, our customer service team will assist you every step of the way to restoring your hot water. Contact us the moment you notice your hot water is no longer working, and we’ll do everything we can to get the right parts installed as soon as possible.