You’re sure that your radiator isn’t producing the heat it previously did. You feel its surface and find that it is hot at the bottom but lukewarm at the top.
The problem? You’ve almost certainly got an airlock. The air has risen to the top of the radiator, preventing the hot water from getting up there.
Diagnosing the airlock problem
One of the most common causes of an airlock is that you’ve had your system drained. You might think this would do nothing but good. After all, it’s sometimes recommended for keeping your system running efficiently. However, if the system is refilled in the wrong order and the top floor radiators aren’t shut off when the downstairs radiators are being filled, air can enter, resulting in no heat.
You may need to call a professional plumber. For boiler installation in Woking, try a reputable local firm such as www.rjplumbingandheating.co.uk.
What to check
First, you should check that the central heating pump is working properly. If it seems to be okay, turning up the pressure may help the airlock to move.
Next, you’ll want to test the radiators. While you are doing this, you need to make sure that at least one radiator is on. Turn the boiler on and check each radiator in turn to make sure that it heats up properly at the top and bottom. If you’re satisfied, leave the one you have just checked on and move on to the radiator that is next in sequence. Once the next radiator is turned on, the previous one can be turned off.
If you find that one radiator is guilty of making the whole system lose warmth, turn that one off. This will allow the other radiators in the system to get extra water pressure.
If each radiator is working fine when you test it on its own but you lose heat when they’re all on at the same time, the problem might be related to balancing. Unfortunately, this tends to be the result of poor installation of the heating system.
One of the remedies that is worth trying is to close the radiator valves to only half of their capacity. This may work until you can get a competent central heating engineer to take a look at the installation.