How to Turn off a Radiator: A Guide for All Valve Types

Last updated on October 13th, 2024

Turning a radiator off can sometimes cause problems, especially on old heating systems with radiator valves that haven’t been touched for many years. They can start leaking and break when using them for the first time.

I have been repairing and replacing radiators for over a decade and I have turned off and on all types of radiator valves many times. Here I’ll show you how to turn off a radiator based on my everyday experiences over the years.

How to Turn off a Radiator

To turn off a radiator you must close one of the valves at either side of the radiator. You can close any of the two valves to turn it off or you can close both valves if you want to remove the radiator.

Having a good pair of water pump pliers is best for turning lockshield valves as it’s much quicker and easier than using an adjustable spanner. Water pump pliers can also grip rounded-off valves or manual valve handles when they are too stiff to turn with your hand.

Thermostatic radiator valve

To turn a radiator off with a thermostatic valve you must turn it clockwise until it’s on ‘off’ or ‘0’. You can also turn it to frost setting (if you have one) which means the radiator will stay off unless the temperature drops to below 5 degrees in that room.

Manual valve

With a manual valve, you need to turn it clockwise with your hand as far as it will go. You might need to start it off by using some water pump pliers as they can be tight when they haven’t been turned for years.

Lockshield

For lockshield valves, you must remove the cap and turn the valve clockwise as far as it will turn with an adjustable spanner, water pump pliers, or some valves will need a hex key to turn it. You should be able to pull or screw the cap off with your hand, but some will have a screw in the middle that needs to be removed.

Towel radiator valve

Turning off a towel radiator is usually easy as they mostly have manual valves. You can turn either one of the valves clockwise as far as it will turn. You might need to use some water pump pliers to get it going.

How to Turn Down a Radiator

You might just want to turn down the temperature of a radiator instead of turning it off.

Here are a few ways:

At the boiler

To turn the temperature of a radiator down you can turn the heating/radiator dial on the boiler down, but this will turn down all of the radiators.

Thermostatic valves

You can also turn the thermostatic radiator valve down to a lower setting but the temperature of the radiator will remain the same as before. The radiator will turn off when the temperature of the room has reached what the thermostatic valve is set to.

Lockshields

The best way to turn a radiator down properly is to partially close a lockshield radiator valve. This is how to balance radiators.

You must turn the valve clockwise as far as it will turn and close it using some water pump pliers or an adjustable spanner. Then open it a quarter turn, keep opening it slightly until it’s at the temperature you want.

How to Check Radiator Valves Are Open

One radiator not working is sometimes caused by the valve being closed without knowing that it’s closed. To check radiator valves are open you need to turn the valves anti-clockwise as far as possible.

If the radiator valve does not turn anti-clockwise then try turning it clockwise to see if it’s moving. If it doesn’t move either way then it must be stuck and you’ll need to force it to free it. The best way is with a decent pair of water pump pliers.

Summary

Turning a radiator off is very simple most of the time, especially if you have thermostatic radiator valves. Just remember to turn any valves clockwise to turn them off and anti-clockwise to turn them on.

There are times when turning off a radiator goes bad like when it causes a radiator valve to leak because it hasn't been touched for so long. In which case you'll need to replace the valve.

Feel free to ask any questions in the comments below, and I’ll do my best to help. If you found this post helpful, please consider sharing it.