All Radiators cold upstairs and hot downstairs

21 Mar 2016
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United Kingdom
Looking for some advice. My brothers has 3 radiators upstairs that aren't heating up but downstairs rads are all hot.

He had a plumber come fix a trv leak on one of the downstairs radiator so not sure if hes done something.
Its the old type of central heating where there is a hot water cylinder tank, a boiler, and pump separately in the cupboard and water tanks in the loft.
I believe the rads have air in them but we've opened all the bleed valves at the top of all the rads and water is coming out which seems ok. Theres also bleed nipples near the copper pipes where they go to the trv and lockshield opened them too and water is coming out of them too but rads are still cold.

Any idea what the correct way to get rid of airlock in these type of system as im not too sure. I know on combi boiler system you just opened the bleed valves on the rads (normally upstairs rads) and then top the boiler from the filling loop.

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remove the trv heads and give the pins a good push incase they are stuck.
bleed a lot of water out of the rads.
check the flow and return pipes are getting hot

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Hi its 3 rads upstairs that are cold and all of the trv pin are fully out.
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I assume the problem with upstairs rads has recently surfaced and all stopped heating simultaneously. Typical of air trapped in the system. So ,close trv 's on ALL rads that get hot ,and on two of the cold ones. With only a demand for central heating on ,not domestic hot water , run the boiler. This should force the flow thru the one rad and it should then heat ,bleeding air if you need to if it collects in the rad. Then open trv on second cold rad ,bleed as required till it heats ,then same on third rad. When they all heat up open all the other trvs. If your ONLY problem is trapped air ,this should sort it.
Hi yes the pipeon 1 radiator is a bit warm up to the trv but its not warming the radiator and on other radiators the pipes are stone cold but if you bleed the radiator water is coming out of the top of it. Is this a airlock or something else.
Someone told me to connect a hose pipe to one of the radiators upstairs and drain it off with the heating off. As you drain the radiator water will fill the system back up from the tank upstairs and keep draining untill you cant hear any guggling sound from the radiators. Does that sound right?
Thanks for your help
Ok i will give that a go later today. The other day I did close all the working radiators but 1 as it had a radiator cover over it so couldn't get to the trv without taking the screws out of the wall but i had all the cold radiators trv' s opened so will try shutting all of them and leave one opened and try running it. Thanks.
Ha ha seriously I had a job like that and found that the feed pipe to the system was blocked with limescale I poked it out and the system filled up and all was well.Bob

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