Photo Courtesy: Simon James
If you are like me, then you would have been revelling in the fact that your central heating has been off for the last few months of summer and your heating bills have subsequently been significantly reduced.
Sadly, we are slowly rolling back around to the time when we need to start considering turning our central heating systems back on. As the cold and wet weather comes back to the UK and elsewhere, we can expect to see an increase in central heating and plumbing issues. Good news for plumbers and heating engineers but sadly not such great news for us that have to pay for it to be fixed. One of the most common problems that are raised concerns radiators that simply aren’t reaching their optimum temperatures.
If after turning your central heating back on you find that your radiators don’t seem to be heating the room in the same way that they previously were, it could be that there is air trapped in your central heating system. This is very common place and signified by cold patches felt in different areas of the radiator – frequently towards the top of the radiator.
Bleeding the Radiators
Before reaching for the yellow pages to look for your local plumber or heating engineer, if you are confident enough one thing you can try is bleeding the radiators. All you need is a Radiator key (available online in most online or high street retailers) and a towel or rag that you are prepared to get a bit wet.
With your central heating switched off, use the radiator key to slowly turn the radiator valve at the top of the radiator. As you do this you will hear a hissing sound as the air (that was blocking your radiator) escapes to be replaced by water. As soon as a little spurt of water escapes from the radiator valve, you know all the air has been replaced with water and it is time to tighten the valve.
You then need to carry out the above process on all of the radiators across the house and once you have finished, go to your boiler and check that the boiler pressure is still retained. The boiler pressure is often signalled on the dial or display of the boiler (depending on what boiler you have), but if you want more confirmation please consult your boiler manual/instructions.
If the water pressure has dropped slightly you may need to re-pressurize it. Often you can reset your boiler or add more water to the boiler system to increase the pressure. Again, please consult your boiler user manual for more information.
Right: Phil checking his boiler pressure with a flashlight and the manufacturer’s manual in hands (wise thinking). Photo Courtesy: Phil and Pam Gradwell
Calling the Experts
If in doubt about any of the above, you may just need to concede defeat and ask the experts in the form of a heating engineer. However learning to bleed a radiator yourself is a valuable life skill that is certainly worth learning. It can save you a lot of time and money and will no doubt significantly reduce the stress levels in your home if your central heating ever stops working properly!
About the author: Tom Key works for Direct Heating Supplies, leading supplier of cheap boilers, including Worcester boilers and Vaillant boilers, and other heating and plumbing supplies.