Category - Boilers
Guide author photo

Ryan Gill, Engineer

31 Jan : Updated 4 Apr ● 4 min read

Is your radiator not heating up? Here's what could be the problem

Ever walk into one of your rooms and notice how unusually cold it is? Your heating is on and all your other rooms seem to be nice and toasty. What’s causing this? It can all get a bit baffling but BOXT is here to shed some light on the problem.

This guide should help you deal with this particular problem and hopefully find out what’s causing your radiator to stay cold. Try out these simple checks, you might even be able to fix the radiator all by yourself. 

If you have hot water but no heating, check out our expert guide.

How's your pressure?

Low boiler pressure is quite common for most households. It always seems to drop and at the most inconvenient time, but when it does all you have to do is top it up and it’ll only take a minute. Simply go to your boiler and find the pressure gauge. If the needle is anywhere in the red section then there’s your problem. 

Topping up a boiler’s pressure is different for every boiler manufacturer. For more modern boilers a filling loop is used. If you have a Worcester Bosch you’ll notice a blue lever. Pull it down whilst keeping an eye on the needle on the pressure gauge. The perfect boiler pressure is between 1 and 2 bars.

Bleed your radiator.

Another quick and easy way to try and get your radiator up and running again is by giving it a quick bleed. Basically, it means that there may be some trapped air in your radiators which stops the heat from circulating, bleeding it releases this air. Here’s how you do it:

  1. Turn off the heating
  2. Find your radiator key and turn the valve at the top of the radiator
  3. You’ll begin to hear a hissing sound, this means the trapped air is escaping
  4. When the hissing stops, retighten the valve
  5. Turn your heating back on
  6. Check radiator 

Check your TRV's.

A common problem we can all face with our radiators is a faulty thermostatic radiator valve (TRV). These are found at the side of your radiator and go from 1-5. To turn the heat up or down you simply need to twist it. However, the head of these valves can sometimes break or in most cases stick. 

The best thing to do would be to contact a professional as it may be a bit tricky to fix the problem on your own. If you live in a rented property, contact your landlord who’ll be able to fix the problem for you. 

Check your thermostat.

If you have a few radiators that aren’t heating up as they should, it could be a thermostat issue. It could be faulty or it may need a quick reset. There are many different types of thermostats all with their own unique way of being reset. 

To reset a Google Nest thermostat, simply hold and press down the ring for a few seconds until it turns off - then release. If the problem continues to wreak havoc then try calling Google Nest support on, 808 169 2307.  For those of you who have an ESi room thermostat, here’s how you reset it. Press and hold the ‘reset’ button for three seconds then release. Give it a try, it just might work.

Time to contact BOXT.

If you’ve done all the above and your radiator still isn’t firing up, then give us a call on 0800 193 7777. When you ring that number you’ll be put through directly to one of our in-house engineers. They’re the heating specialists who will help you with any boiler-related issue, so be sure to pick their brains. Alternatively, if you don’t have time - why not drop us a message on our Live Chat? You’ll get an instant response, and our engineers will help you in any way they can, from simple boiler services to full-blown boiler replacements

Boiler issues?

Boiler issues?

We fix 70% of issues for a one-off fixed £89 fee

Book a boiler repair
Share this post