Why Are My Radiators Getting Hot When the Heating Is Off?

18 November 2024

Due to the rising cost of living, conserving energy to save on bills is an important factor. If you are heating rooms that you don’t particularly use much you could be wasting energy, even worse if your central heating comes on when you are not calling for it to and radiators getting hot. In this guide we will explore reasons as to why your central heating may be coming on, even when you are not calling for heat. There could be several reasons or faults as to why your radiators getting hot when the central heating is switched off.

How to Fix a Stuck Diverter Valve Issues

A broken or stuck diverter valve can be a common boiler breakdown issue. The diverter valve directs hot water within the central heating system to either the radiators or hot water taps. If the diverter valve is malfunctioning it can remain stuck. This could mean that hot water will flow constantly around the radiators, even when your thermostat is turned off. Wear and tear, sludge build up or magnetite can be several reasons as to why your diverter valve is faulty, or preventing the valve from closing.

Consequently if your radiators getting hot when the hot water is on, the diverter valve may be stuck in mid position. If you suspect there is a problem with the diverter valve our advice is to contact a Gas Safe registered heating engineer to check the valve. You may need to replace the diverter valve, but on some occasions the heating engineer may be able to manually allow the valve to move from its stuck position. If you have a combi boiler and it is still under warranty you may have the valve covered under boiler warranty.

Check Valve Problems

If your radiators getting hot when the heating is turned off and the diverter valve is working fine, you may have an issue with your check valve. The check valve is in older boilers and prevents the central heating retaining heat through natural convection. Some systems have an electronically controlled solenoid valve to perform the similar function.

FAQ

frequently asked questions

How To Fix It

Why Does My Boiler Keep Firing Up When the Heating Is Off?

There is a pre-heat function on combi boilers that can mean the boiler will fire up on occasions, to ensure hot water is available in an instant when you turn the hot water tap on. If the boiler did not do this you would have to run your hot tap a while to get hot water - this would lead to increased energy bills.

Why Is My Bathroom Radiator On When the Heating Is Off?

In some older systems, the bathroom radiator or heated towel rail is connected to the hot water circuit. This means when your hot water is on this will heat the bathroom radiator. This is an inefficient way to heat your bathroom. With a combi boiler you will not have this issue as the radiator will be linked into your heating circuit.

Why Are My Radiators Not Turning Off?

If your radiators getting hot still when you turn the heating off, the diverter valve is likely to be the issue. The diverter valve being stuck in the open position will continuously send hot water to the heating and to radiators. This will cause the radiators to be on even with the thermostat being turned off.

What to Do When the Heating Is Off and the Radiators Are On?

It is best to contact a fully Gas Safe registered heating engineer if your radiators are on when the heating is off. Seeking professional advice will help you to minimise your energy costs ensure your central heating system is more efficient.

What You’ll Learn Here

How to Fix a Stuck Diverter Valve Issues

Check Valve Problems

Why Are My Radiators Getting Hot When the Heating Is Off?

The Process of Installing Boilers

How to Fix a Boiler Diverter Valve