How do I make sure my radiators are heat efficient?
30 January 2023
With energy prices soaring, nobody wants to waste money on inefficient radiators.
3 Quick and easy steps to ensure you’re heating efficiently
As the evenings draw in and the temperature drops, you’ll naturally think about turning on your central heating – run these three quick checks to ensure you’re not wasting money on inefficient radiators.
1 - Bleed your radiators to make sure there’s no trapped air
Gurgling noises or cold spots at the top of a radiator are all giveaways that you need to bleed it, releasing trapped air and enabling the central heating system to work more efficiently.
Air naturally builds up in a plumbed heating system over time, which will stop it working efficiently and create cold spots. Air can be introduced into a central heating system in several ways, for example when new water enters the system from the expansion tank or when a routine maintenance is carried out.
To see if your radiators need bleeding is simple. Feel your radiator at the bottom and around the inlet pipes. Typically it will be nice and hot but as you move your hands up the radiator body, if it starts to get cooler – it’s got trapped air. This is because any air trapped in the radiator naturally rises to the top, and because the water can’t fully fill the radiator, it can’t heat it. The trapped air needs to be ‘bled’ using your radiator key to turn the valve at the top of the radiator. You should hear a hissing sound. This is the trapped air escaping. When water starts pouring from the valve, you’ve bled the air and the top of the radiator should now start to heat up.
2 – Balance your central heating system
Another issue you might encounter is that some radiators heat up fast while others take a while. If that’s the case, knowing how to balance radiators could solve your problem, and ensure hot water from the boiler is distributed evenly. Using the valves on the radiators, you will strategically restrict the flow to ensure that the hot water produced by the central heating boiler is distributed evenly across the system.
a) Turn the heating off and prepare the system
To balance your system all radiators must have been bled recently, and the heating must be off, and the radiators cold. You must also have all the radiator valves in a fully open position. Thermostatic valves are easily opened by hand, the standard lockshield valves will need a spanner or valve key and can be opened by turning anti-clockwise.
b) Turn the heating on and record the order and rate your radiators heat up
When your central heating is switched on, with all the valves open, the hot water will rapidly flush through the system, heating up the radiators as it does so. The catch here is you’ll probably need some help – especially if you don’t know the order in which the hot water flows around the system. Once you have the order, you’ll need to turn the heating off and let it fully cool again.
c) Now you have the order it’s time to control the flow
Repeating the previous step, but this time you’ll need to adjust and control the flow of hot water around the system. The first radiator to heat up will always get the hottest water so it needs the flow restricting the most – so close the lockshield valve fully, then open one quarter turn. Depending how precise you want to be you could use a thermometer. The target is a 12c difference between the inlet pipe and the outlet pipe, this is achieved by carefully and precisely opening up the lockshield valve. It's important to remember balancing radiators takes time. You'll need to wait for the temperature of the radiator to change each time you adjust the lockshield before you can get an accurate measurement.
d) Be patient, repeat the process in the order the radiators take heat
With the first radiator with a difference of 12c between the inlet and outlet pipes, it’s balanced. You need to repeat the process with the other radiators in the order they heated up. The overall objective is to force the hot water to the radiator furthest away from the boiler on the central heating system. By ensuring the flow reaches this ‘furthest point’ before the water has significantly cooled, will allow the last radiator on the system to efficiently heat the space in its zone.
3 – Give radiators space to make sure air can circulate freely
With your radiators bled and balanced they should now be heating the space in their respective zones efficiently. One thing typically overlooked is the air flow around the radiator itself. Often there will be some impediment to the airflow, this could be as simple as soft furnishings positioned too close to the radiator. The radiator heats the room largely by convection (hot air rising and circulating around the room), and only about 20% through radiating heat. If there is a large object, especially a soft ‘heat absorbing’ piece of furniture, the radiator could be working efficiently – just not heating the space!
If you have old radiators, they could be suffering from sludge deposits, which means bleeding and balancing will only help to a point. You’ll need the system draining down and flushing through – and if you’re going to that trouble you may well explore replacing some, or all, of your radiators with more energy efficient modern designer radiators.
With so many brands, styles, sizes and colours to choose from, without a bit of expert help, it can be difficult to know where to start. If you would like to know more information about our radiator ranges within our portfolio, then call us on 01530 564122 or get in touch via the contact form on our website.
