A cool radiator can be a serious problem during the chilly winters, but the solution isn’t always to turn up your thermostat or your TRVs. If the radiators in your home are failing to heat up, or aren’t emitting as much heat as they should, then it could be because of one of the following problems.
Trapped Air
Trapped air in your central heating systems can cause your radiators to feel completely cold, or have cold spots. Bleeding your radiators will release the air allowing them to heat properly. Releasing trapped air from your radiators can even help you reduce your heating costs, as you’ll find that your heating may not need to be on for as long and that your thermostat doesn’t need to be set as high.
Easy to fix?
Trapped air can be released from your radiator by bleeding them. The process can be simple and you can read how to do so in our guide. You may find that you need to bleed all of the radiators in your home rather than just one.
Low Pressure
Your radiators could be cold because there isn’t enough water pressure to circulate hot water throughout your home. This means that you will need to re-pressurise your boiler. Most boilers will have a pressure indicator, which should be set between 1 and 2 bar.
Easy to fix?
If your boiler pressure is below 1 bar, then it will need to be re-pressurised. You can re-pressurise your boiler yourself, providing that the system is turned off and cooled. Refer to your boiler’s manual for advice on re-pressurising and, if unsure, get a professional to help.
Radiator Sludge
A build-up of dirt in your radiators can stop it from heating properly. Sludge build up lying at the bottom of a radiator can prevent every panel of your radiator heating up. You can check to see if your radiator has sludge by bleeding the radiator and checking to see if the water is discoloured.
Easy to fix?
To remove sludge from your central heating system, you will need to power flush the system. Power flushing will need to be carried out by a trained engineer. Having the system power flushed will remove rust and limescale from the system, allowing water to flow with ease through the radiator.
If you require assistance with radiator or boiler servicing in Bristol, then get in touch with the team at DHS. Whether you’ve found a fault with your system, or require an annual boiler service, our Gas Safe registered engineers can make sure your central heating runs efficiently throughout the year.
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