What to do if your radiators aren’t getting hot

5 quick checks you can do yourself before you call your plumber.

I get so many call outs to customers who have problems with their heating systems that I realised I needed to address this issue.

Now, of course I’m happy to help my customers with their systems (after all it’s what my business runs on… helping solve customers plumbing problems), but as I’ve got increasingly busy with work, it’s become almost impossible to attend to every inquiry I get.

So I’m going to address the most common issues that people have with their system, and that is the problem of their radiators not getting hot.

So if you’re experiencing cold radiators, or even cold spots in your radiators then read on to find out what you should check for before calling a plumber out.

Here are 5 quick checks you should do first (and they may seem a little obvious) but it’s always good to have something to refer to as a checklist.

1. Is your boiler running?

Make sure power to your boiler is on, that your gas light is on and that your boiler is kicking in when triggered. If you have a combi-boiler then turn on a hot tap in the house and see if the boiler responds. If you have a hot water cylinder then you’ll need to check that you are getting hot water stored during the times you have it set to.

2. Is your boiler pressure correct?

Take a look at the pressure dial on your boiler (usually found by peering underneath the bottom of the boiler). The pressure needle should sit between 1 and 1.5. If the needle is lower then you need to use the filling loop on your boiler to increase the pressure. Check your boiler instruction manual to find out how to do this for your particular boiler model.

Once you’ve checked these two points and you know your boiler is working properly, then it’s time to move on to the next check. If however, none of these checks yield a positive, then you’ll need to call out your gas engineer.

3. Is your thermostat high enough?

This may seem an obvious check, but there are many customers houses I’ve been to where they’ve not had their thermostat set high enough for the boiler to kick in. I usually advise about 20 degrees, but this will depend on your own personal preference for heat. If your thermostat is set too low, and is in an area of your house which is usually warmer than the rest of the house, then this may be the reason your boiler is kicking in to heat your radiators.

4. Is there air trapped in your radiator?

Often, trapped air can work its way to a natural place of build up which is often in a radiator, so you need to make sure all the air is out of your radiators for them to heat properly. Trapped air prevents the full flow of water through a radiator which will leave them cold in either the bottom or the top. Take a radiator key and an old towel, and open the valve at the top of the radiator to allow the air to escape. This is known as bleeding a radiator. Once the air is removed, you should start to feel the radiator getting warm (if your heating is switched on).

5. Is your radiator thermostatic valve working properly?

This is the final check to see what could be causing an issue. Thermostatic valves control the temperature of the radiators so you can control temperatures throughout your house. Most new radiators are fitted with valves, however if your system is old then you may want to consider adding valves to all your radiators to have a more efficient system.

If you have thermostatic valves in place, then you should check they’re working properly by removing the head of the valve and making sure the pin is moving in and out freely.

What if your radiators are STILL not getting hot?

If you go through these 5 points and find no fault, then it’s possible that your heating system could do with a little love and attention. If you’ve never had your system serviced before (I’m not talking about your boiler, but your full system which includes your pipes and radiators) then you may find that it has years of built up scale and grime, causing your boiler to worker harder than it needs to and creating problems like cold radiators.

If you’re thinking that your system could probably do with a clean, because either:

1. you’re experiencing these problems, or

2. you know that your system hasn’t been cleaned in years,

…then you might want to consider a power flush.

It can solve many system problems whilst also preventing bigger issues further down the line. After all, no one wants to face a new boiler boiler replacement or worse, a whole system replacement (think of all those pipes!) which can be pricey and usually happen at the worst times – like when you have guests staying, or it’s the dead of winter!

Take action today and give your system the service it deserves with a professional power flush.

If you’re in the Wiltshire area, you can contact us for a free quote. Give yourself the peace of mind knowing that you have a professional making sure your system is working at it’s best.