Radiator Not Working

If your radiator is not working or heating up properly, then watch the video which shows you some simple checks and fixes you can do.

This article and video shares what the possible causes might be for a radiator not working and shows you radiator bleeding and what to when the radiator valve is stuck. And there’s also some other little tips and tricks that we can do to get your radiator heating nice and warm again. 

Short on time?

The quickest and stress-free way to get your electric boiler working again is to call us out. Our vans carry many common spare parts so we can usually get your heating working in the same visit. Contact us for a no-obligation phone consultation/quote. We cover locations in North London, West London, Watford, Herts and Middx and nearby.

Time needed: 10 minutes.

Quick Checks to Solve a Radiator Not Heating Up

  1. Bleed the radiator

    Using a bleed key and rag to catch any water drips

  2. Check the thermostatic valve

    With grips, remove the thermostatic valve head and tap the pin to loosen it. Make sure the valve head is at its highest setting before fixed back on.

  3. Check the Lockshield Valve

    Make sure the thermostatic valve is fully open, then using the grips, turn the Lockshield valve fully open

  4. Still not working? Or don’t have the right tools? Or simply don’t want to do this?

    Contact us for a call out

Indications That The Radiator Is Not Heating Up

When you feel your radiator with your hand you may notice that the radiator is not heating all the way to the top. It might even feel pretty cool at the top and this is normally a good sign that the radiator needs bleeding.

How To Bleed A Radiator

The only tool you need to bleed a radiator is a radiator key. Inside one end of the key is a square shaped hollow which fits over the radiator bleed valve. The radiator bleed valve is usually located at one of the top corners of the radiator.

You’ll also need a rag or cloth for cleaning up any spills.

Place the rag underneath the bleed valve, to catch and mop up any spills of water.

Next place the key in so it slots nicely over the square radiator bleed valve and then turn the key anticlockwise to open it until you hear a hissing sound.

The hissing sound is air escaping that was trapped at the top of the radiator. As the air escapes, water fills up the radiator.

When water starts to come out and the hissing stops, then you have succeeded in the bleeding the radiator and you can now turn the radiator key clockwise to close the radiator valve.

Use the rag to catch and mop up any water that’s escaped.

The radiator should start warming up. Job done. You’ve now successfully bled the radiator.

A Stuck Radiator Valve

The radiator valve sits at the bottom (usually right) of the radiator. It consists of a knob that you turn to increase or decrease the heat. There are numbers from 0 to 5 or 7 indicating how low/high the thermostat is set.

Hot water from the boiler should flow through the valve. A reason why a radiator stops heating is because this hot water stops going through the valve to the radiator. And the reason this happens is because the thermostat get stuck down.

This typically happens after a hot spell or summer. During summer you turn the radiator valves to 0 or * position so it’s effectively off.

Then as the days get colder as we approach winter, and you want your radiators on, when you try to open the valve back up again and the valve is hard to turn. It’s stuck.

Here’s How A Thermostatic Radiator Valve Works

Inside the thermostatic valve is a pin which rises and falls as you turn the valve on/off. As you open the valve the pin rises and allows more hot water to flow into the radiator making it hot. This pin can get stuck, particularly through summer when it’s not being used.

The good news is, it’s fairly easy to fix with a pair of grips and a screwdriver.

How To Release A Radiator Valve That’s Stuck

You will need a pair of grips and sometimes a screwdriver to unscrew a little screw to take the head off.

Take the head off, releasing any screw that might be holding the head in place and using the grips to undo the large nut below the head (watch the video to see exactly what to do).

When you’ve taken the head off, you’ll see the pin. That pin gets stuck in the down position, give the pin a tap to loosen it up. When the pin is moving freely up and down, you’ll be able to feel that the radiator starts to warm up as the warm water flows through.

When the radiator starts warming up, put the valve back on making sure the valve is turned up to maximum. Then tightened with the grips.

Leave it open generally for a day so it can circulate through as there might be some dirt inside that’s got it stuck down.

Radiator Still Not Working?

If your radiator still isn’t working then it’s an indication that the Lockshield valve is also stuck. The lockshield valve sits on the other side of  the radiator. Radiators have 2 valves one at each end of it – one is the thermostatic valve, the other is called the Lockshield valve.

How To Unstuck The Lockshield Valve.

First make sure that the thermostatic valve on the other side is fully open.

Don’t be deceived thinking the Lockshield valve is open as sometimes the plastic breaks inside.

So use a pair of grips and make sure that this end is open by turning it fully anti-clockwise.

This will increase the flow through the radiator and should improve the flow and get the radiator nice and hot.

What To Do When A Radiator Is Not Working

So to get your radiator heating again I’ve explained:

  1. bleeding your radiator
  2. fixing your stuck radiator valve
  3. fixing your stuck Lockshield valve.

Do these things are the first steps to getting the circulation working back through your radiators. This nearly always happens after the summer or a period of when the radiators have been turned off.

If You Still Have Heating Problems

If you’re still having problems, then it could mean something else is wrong and it’s time to call a heating engineer out like us, so please contact us using the Get A Quote form or phone us.

We provide Heating Services in London, Watford, Hertfordshire and Middlesex areas. Check our locations served page to make sure we call out to your area.

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