please help with replacing a radiator

26 Sep 2010
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United Kingdom
hi please could someone help we have a new combi boiler in our loft we have a radiator with a leek and my husband wants to change it he has done this before when we had our old behind the fire boiler what he wants to know is how do you turn the water off to the radiators when you drain the system and stop the radiators filling up. Thanks
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if your only changing a rad then you don't need to drain the system just shut both rad valves and drain the rad your changing.
hi thanks for your reply my husband as just said that he is going to get a smaller one as we get too hot with the big one so he will need to add some pipe will you need to drain the system then please
then close the rad down abit if it gets to hot.
is it fitted with a trv ?
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drain the system YES. should be a drain off located downstairs on the furthest pipe from boiler, or just above stopcock, attatch hose. if you get a smaller rad and you have a wallpapered wall, obv you will need to replace section of paper. will have to add pipe (not pushfit) depending on your reduced size, could get extensions from your valves, i'd go for a trv if not already got one. unless you have a room thermostat.
If you have a combi boiler it means your system is sealed. Therefore you do not need to worry about turning off any means of water.

Just drain down your system via a drain off valve (until the gage on your boiler reaches 0) and do the work and when it comes to refilling there should be a filling loop near your boiler will two quarter turn valves on to re pressurise the system up to 1.5 bar.
hi thanks for your reply is this right we turn the combi boiler off then drain the system replace the radiator? also where do you put the inhibitor in the system? hopefully by changing the raditor will stop our new combi boiler from turning off


as we have a radiator leak so that is why it turns off with error f37 so someone said on my other listing

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