Bleeding A Radiator: UK Guide

As the pleasant warmth of summer gradually gives way to the cooler temperatures of autumn, it’s time to start thinking about getting your home ready for the winter months.

One essential aspect of winter preparation is ensuring that your radiators are in top-notch condition to keep you and your family warm and comfortable. After being dormant during the summer months, radiators may require some attention to ensure they function efficiently when you need them the most. Specifically, radiators will need bleeding, and bleeding in order.

In this guide, I’ll walk you through the process of getting your radiators ready for winter, including the crucial step of bleeding a radiator.

I’ll also show you the importance of bleeding radiators in order.

Don’t worry though, bleeding a radiator is not as hard as it sounds. In fact, bleeding a radiator is an easy DIY job that anyone can do.

Below is a handy table of contents. Clicking on any of the article headers below will jump you straight to the place on this page you are interested in. I am an Amazon Associate, and earn commissions on qualifying purchases.

Step 1: Inspect And Clean

Before the cold sets in, it’s important to give your radiators a thorough inspection. Dust, dirt, and debris can accumulate on the surface and fins of the radiator, reducing its heat output.

Use a soft brush or a vacuum cleaner attachment to gently remove any dust and debris.

It’s also beneficial to wipe down the surfaces of your radiators with a damp cloth to get rid of any remaining dirt. This also prevents the dust from becoming airborne once the radiators are producing heat.

Cleaning your radiators will also keep them in good aesthetic condition.

Step 2: Check for Leaks

While inspecting the radiators, keep an eye out for any signs of leaks. Look for water stains or damp spots around the base of the radiator, and around carpet or flooring areas.

bleeding radiators uk homes

Leaks can lead to reduced efficiency and potential water damage to your floors and walls.

If you find any leaks, it’s advisable to seek the professional help of a qualified plumber.

Step 3: Bleed the Radiators

Bleeding a radiator is a crucial step in maintaining its efficiency and effectiveness.

Over time, air can accumulate inside the radiator, causing cold spots and reducing their ability to heat the room effectively.

Bleeding a radiator releases trapped air and ensures that hot water can flow freely, providing consistent heat distribution through the surface of a radiator.

Money Saving Alert

Bleeding your radiators will actually help with your energy costs.

Bleeding a radiator will save you money.

Radiators with trapped air inside them won’t heat the room as effectively as a bled radiator. The knock-on effect of this is a higher energy bill because you’ll keep the heating on for longer to compensate for the inefficiency of your radiators.

Here’s how to bleed A radiator: UK Step By Step

Ensure you have the necessary tools at hand before you start the job.

You’ll need:

  • a radiator key
  • a cloth or towel to catch any drips
  • a container to collect any excess water
WZ Radiator Bleed Key- Radiator Valve Clock Key for Bleeding and Air Vent- Made of Solid Brass- Pack of 2
5,535 Reviews
WZ Radiator Bleed Key- Radiator Valve Clock Key for Bleeding and Air Vent- Made of Solid Brass- Pack of 2
  • Material: Solid Brass Radiator bleeder
  • Usability: Easy to grip Clock style key for bleeding the radiator with ease

STEP 1: Turn off the heating: Before you start, make sure your central heating system is turned off. This prevents hot water from spewing out when you release the air from the radiator.

STEP 2: Identify the radiators in your home. Start with the radiator furthermost from your boiler and work inwards on the ground floor, finishing with the radiator nearest your boiler. Repeat the process in the same order on the 1st floor.

STEP 3: Identify the bleed valve: Locate the bleed valve at the top of the radiator. It usually looks like a small square nut or a protruding valve with a slot for the radiator key. (See image below).

bleed valve bleed a radiator
Typical bleed valve on a radiator

STEP 4: Position the container: Place the container underneath the bleed valve to catch any water that comes out.

STEP 5: Open the valve: Insert the radiator key into the bleed valve and turn it counterclockwise (usually a quarter turn). You’ll hear a hissing sound as the trapped air escapes. As soon as you hear a steady stream of water, be prepared to close the valve.

bleed a radiator uk homes

STEP 6: Close the valve: Once water starts flowing steadily without any air bubbles, quickly close the valve by turning it clockwise. Make sure not to overtighten it.

STEP 7: Wipe and clean: Wipe off any water drips and ensure the area around the bleed valve is dry.

STEP 8: Repeat for all other radiators, finishing with the radiator closest to your boiler.

STEP 9: Check the pressure: Bleeding the radiators can sometimes lead to a drop in the system’s pressure. Check the pressure gauge on your boiler and, if necessary, follow the manufacturer’s instructions to top up the pressure.

STEP 10: Turn the heating back on: Once you’ve bled all the radiators and ensured the pressure is correct, you can turn the heating system back on.

Bleeding Radiators In Order

Bleeding radiators in order is important.

Bleeding radiators in order (as stated above), will ensure all air is released from your radiators. Doing it in the incorrect order will result in air being left in radiators, due to the way the pressure in the system works.

Always start with the radiator furthest from your boiler, for best results.

Step 4: Regular Maintenance

To keep your radiators functioning efficiently throughout the winter, consider these additional tips.

  1. Keep your boiler in tip-top condition by getting your boiler serviced regularly by a professional.
  2. Ensure there’s adequate space between radiators and furniture. Always leave space to allow for efficient air circulation.
  3. Periodically check for any leaks or rust patches appearing on your radiators.
  4. Consider installing reflectors behind your radiators
BLOSTM Radiator Insulation Foil 5m x 60cm - Bubble Insulation Foil Reflector Thick Heat Reflective Bubble Wrap Radiator Foil Reflector with Adhesive Pads Saves Energy - Covers 3+ Radiators
1,374 Reviews
BLOSTM Radiator Insulation Foil 5m x 60cm – Bubble Insulation Foil Reflector Thick Heat Reflective Bubble Wrap Radiator Foil Reflector with Adhesive Pads Saves Energy – Covers 3+ Radiators
  • ENERGY EFFICIENT – This reflective bubble foil insulation reflects 97% of the heat back into your room. There is less energy needed to heat your home with radiator reflector panels; so you can turn the temperature down. Helping reduce your carbon footprint with the BLOSTM Radiator Reflective Foil.

Check Your Boiler & Radiators BEFORE The Cold Weather Starts

Plumbers hit their busy peak when temperatures drop, usually around September or October.

It’s their busy period because millions of people turn their central heating on, with some, unfortunately, experiencing problems that require them to call a plumber.

So my best advice here is to check your boiler and central heating system, including radiators before the weather starts getting cold.

If you do find a problem, you’re ahead of the game; you won’t face a lengthy wait, and you’ll get a plumber much quicker than if you were calling them out in September or October.


Getting your radiators ready for winter is an essential part of home maintenance in the UK.

By following these steps and learning why bleeding a radiator is important, you’ll ensure that they operate efficiently and provide the warmth you need during the colder months.

Regular maintenance and attention to detail can go a long way in keeping your home comfortable and cosy throughout the winter season.

Other Articles You May Like

Here’s a small selection of articles you may also like from this site:

Here’s the complete list of products and links mentioned on this page.

Here are the sources used for this article on bleeding a radiator:

Questions & Comments

If you have a question or a comment on this article on bleeding a radiator or bleeding radiators in order, please use the comments box below.

I’ll try my best to reply to each and every one of your questions, comments and suggestions.

Stay Safe. Stay Secure.


My name is Richard.

I'm 40 years old. And I have nearly 20 years experience in various safety and security industries.

I'm here for you, sharing all my knowledge and experience to help you create a safe and secure home for you and your family.

Socials: Youtube / Twitter / Contact Me

Leave a comment