Changing a radiator without draining the system

If an old-style radiator is making your home look dated, replacing it with a more modern unit can be achieved in just a few hours by any competent DIYer. As long as the replacement radiator is approximately the same size and length as the original and you are not changing any other parts of the pipework or upstands, there is no need to drain down the entire system before getting to work.

Changing a radiator without draining the system

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Although the procedure is straightforward, it’s a good idea to ensure you know where your stopcocks are located so that you’re able to shut off the water supply to your home promptly should the need arise.


In order to remove a radiator, you’ll need to unscrew the two valves holding it in place and drain out all of the water that is inside. You’ll also need a supply of old sheets or towels to soak up any excess water that might spill out during the process.

Keep a record of the number of turns needed to fully shut the lockshield valve that controls the flow of water through the system because the same number of turns should be used to open the valve once the new radiator has been installed. Before hanging the new radiator, wrap PTFE tape around the screw threads of the adaptors to ensure a watertight seal.

If you’re replacing a radiator because your system isn’t heating as efficiently as you’d like, this might not be the best approach. A far better idea is to change the boiler itself or update your controls to allow you to use your heating system more efficiently.


If a major part of your system breaks down and you suddenly find yourself in need of boiler repair in Brighton or heating checks in Hove, not only will a professional get the job done far faster and with less fuss than if you did it yourself, you’ll also benefit from work that is fully guaranteed. Thankfully, arranging Brighton boiler repair through Glowzone or other providers is generally quick and easy.

Without the right tools and experience, seemingly simple DIY jobs can end up taking far longer than they should and could even lead to parts of your home being damaged, which could cost you far more in the long run.