How To Balance Radiators
How To Balance Radiators
When you turn your heating on, all the radiators in your house should heat up evenly, reaching the same temperature at about the same time. If they do, this means your heating system is well balanced.
If some rooms take longer to warm up or if some are always colder than others, this is a sign that your radiators aren’t well balanced. You might also notice your energy bills are higher than you expect.
Balancing radiators is a job you can do yourself if you have some DIY experience. It’s a relatively simple job that takes a bit of time, a bit of know-how and a few simple tools. The basic tools you need are a radiator bleed key, a lockshield valve key or an adjustable wrench and a thermometer.
In this guide, we’ll explain how to balance radiators. We’ll also explain how to balance radiators without a thermometer and why you should aim for an inflowing and outflowing temperature difference of 12 degrees when you’re balancing radiators.
When you balance your radiators, you adjust the amount of water flowing to each of them, so they all heat up evenly. With well balanced radiators, your heating will warm your whole house, and your heating system will work more efficiently.
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What is radiator balancing?
When you balance your radiators, you adjust the valves that control each radiator to make sure all the radiators in your house receive the same amount of heat. Well balanced radiators heat everywhere in your house up equally and they work more efficiently.
If a heating system is set up without any control over how water flows around the home, the hot water will not naturally flow equally to everywhere. It is much easier, for example, for water to reach the radiator nearest the boiler than the one furthest away. Without any control, the nearest radiator will get most of the heat.
Radiators are built with radiator valves so we can control the water flow. When we balance radiators, we fine tune the whole system so that everywhere in your house gets the same amount of heat.
It’s a good idea to balance your radiators if you notice a problem or if there are repairs or alterations made to your heating system. Installing a new radiator or fitting certain radiator parts or accessories might mean you need to balance the whole system.
Removing an old radiator to replace it with a new one is another job people sometimes do for themselves. Find out how to remove a radiator.
Do you need to balance your radiators or just bleed them?
Some problems with radiators can be solved by bleeding problematic radiators rather than balancing the entire system. If your system seems to be well balanced but you notice some radiators have cold patches or make gargling noises, you might be able to just bleed your radiators.
If you’re not sure what the problem is, it’s a good idea to bleed your radiators and balance them as well. The steps in this guide include both processes.
Balancing radiators: Why 12 degrees?
When you’re balancing radiators, you should aim for a 12 degree difference between the inflowing and outflowing temperature at each radiator. A 12 degree loss of temperature at each radiator is ideal for good heat distribution, efficient heat transfer and efficient boiler operation.
The best method is to use a thermometer to check the difference between inflowing and outflowing temperatures at each radiator in your system.
What tools do you need to balance a radiator?
Here are all the tools you need to balance radiators:
- Radiator key – use this to bleed your radiators before you balance them.
- Towel and bucket – for clearing up water when you bleed your radiators.
- Lockshield valve key or adjustable wrench - for adjusting the lockshield valves that control the water flow to your radiators.
- Flathead screwdriver – sometimes you need a flathead screwdriver to remove the cap on the lockshield valves.
- Thermometer - for checking the temperature of your radiators. A non-contact thermometer is best.
Most heating systems in the UK are made with the same basic components, so these tools should work for balancing all radiators in the UK.
How to balance a radiator Step-by step
You can balance radiators at any time of year. But in the UK, balancing radiators is a good job for when it isn’t freezing cold because you have to turn your heating system completely off. In this section, we’ll explain how to balance your radiators.
Step 1. Turn off your heating system
Turn off your central heating and let the entire system cool down before you do anything else.
Step 2. Bleed all radiators
It’s not essential to bleed your radiators when you balance them, but it’s definitely a good idea. This will help your radiators heat up equally, and it will make sure you get accurate temperature readings when you’re balancing the system.
Bleeding radiators is simple. Just release air from the bleed valves.
Remember heated towel rails
Make sure you include heated towel rails when you’re bleeding and balancing your radiators. They are part of the system and should be treated the same as radiators.
Step 3. Open all your radiator valves
After you’ve bled all your radiators, you should open the valves on all your radiators. This is in preparation for turning your heating back on.
Take the cap off the lockshield valve on each radiator so you can access it. For some lockshield valves, you’ll need a flathead screwdriver to take the cap off. Once you have access to the valve, use your lockshield valve key or adjustable wrench to open it completely.
Turn the valve anti-clockwise to open it.
If your radiators have thermostatic radiator valves (TRVs), make sure these are all fully open as well. You’ll need to manually adjust each valve. If you have smart TRVs, each valve also needs to be manually set to fully open.
Step 4. Find out what order your radiators heat up in
Knowing what order your radiators heat up in will help you understand how to balance your radiators. Normally, the radiators closest to the boiler heat up fastest.
Turn on your heating and monitor your radiators to see what order they heat up in. You can use a thermometer, or you can check carefully by hand. It might be a good idea to get someone to help you at this point.
List all your radiators in the order in which they heat up.
Step 5. Turn off the heating system
Next, you should turn off your entire heating system again and let everything cool down. This will help you adjust the flow at each of your radiators accurately.
Step 6. Adjust the lockshield valve on the fastest heating radiator
The next step is to adjust the lockshield valve on the first radiator in your system for an optimised heat flow. This is the most important part of how to balance radiators.
Before you do anything, completely close the lockshield valve on it. After this, open it by about ¼ of a turn and turn your heating system back on.
Wait for your heating system to fully heat up and then use your thermometer to read the temperature on the radiator. Measure the temperature where the inflow pipe enters the radiator (normally, on the opposite side to the lockshield valve). Then go to the other side, and measure the temperature at a point after the pipework leaves the radiator.
After this, adjust the lockshield valve until you achieve a 12 degree difference between the inflowing and outflowing temperature of the radiator. It will probably take a few attempts.
Be careful to give the radiator enough time to change temperature completely every time you adjust the lockshield valve.
Step 7. Repeat for all other radiators
After you’ve achieved a 12 degree inflow and outflow temperature difference for the first radiator in your system, you can repeat the process for all your other radiators.
Move on to the next radiator in the system to repeat the process. You’ll need to completely close the lockshield valve at each radiator before you start and allow it to cool down completely before you begin to readjust it.
As you move further and further away from your boiler, you can start to open the lockshield valve more at the first adjustment.
Step 8. Check the system
After you’ve finished, make sure you check the inflowing and outflowing temperature at each radiator to see if you need to make any more adjustments. Once you’re finished, you’ll have a well balanced radiator system.
After you’ve finished balancing your system, you can readjust the thermostatic radiator valves as normal.
How to balance radiators without a thermometer
It is possible to balance radiators without a thermometer if you don’t have one available, although it will take longer and you won’t be able to adjust your radiators as accurately.
To balance radiators without a thermometer, bleed your radiators, fully open all the lockshield valves and turn on your heating system. Then allow your entire heating system to heat up completely. The next step is to gradually close the lockshield valves on any radiators that feel hotter than others until you achieve an even temperature between all your radiators.
Key takeaways when balancing radiators
Well balanced radiators will keep your whole house warm, and they could save you money on your energy bills. Make sure you check your radiators from time to time in case they need balancing. Always check after you have work done to your heating system as well, like fitting new radiators.
New, modern radiators are more energy efficient, they need less maintenance, and they often look better than older ones. They also warm up faster and are less prone to problems with heat distribution. Find out about buying new radiators in the radiator buying guide.
One important thing to know about, when it comes to fitting new radiators, is BTU ratings. Radiators are all manufactured with a BTU rating, which indicates how much heat they will deliver to a room. It’s important to match a radiator’s BTU rating to the size and heating demands of the room it will be fitted in.
Choosing radiators with the correct BTU ratings will make sure all your rooms are warm enough and help to balance your entire heating system.