Help- i have replaced pump and valve but have a air lock in the tank in the loft tried draining but water does not come out...can some one help please.emails would be help full getting very cold.
Clyde
- posted
18 years ago
air lock in tank in the loft for heating
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- posted
18 years ago
By valve do you mean the valve that stops the feed from the tank into the system. If so I did this a few weeks ago on my hot water system and couldn't get HW when I refilled the header tank and turned it back on. It took me ages and much head scratching and redraining and refilling before I stumbled across the solution. I was thinking the problem must be the new valve wasn't opening so I undid the compression nut on the 'feed' side and after a little jiggle I heard air coming out and eventually water, rather like bleeding a radiator. I tightened everything back up and hey presto hot water. Your problem may not be the same but maybe worth a go.
HTH
John
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- posted
18 years ago
On 21 Mar 2006 18:18:11 -0800 someone who may be snipped-for-privacy@clydekirtonjewellerydesigns.co.uk wrote this:-
This pump is presumably the central heating pump and the valve(s) the one(s) either side of it.
What sort of tank do you have in the loft? If it is a feed and expansion tank (a small one) then how do you have an air lock in it? Do you mean that water is not flowing out of it into the heating system?
You tried draining what?
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- posted
18 years ago
what kind of tank is it? header, h/w cylinder, chiefton!
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- posted
18 years ago
If you mean that water doesn't go out of your F&E tank with any drain point open on the CH pipework, or a radiator valve disconnected or any other point in the system opened, then you've probably got a blockage between the outlet of the tank and where it connects into the system. This can be caused either by crud from the tank having got drawn down into the pipework or scale having deposited where the cold fresh water from the tank meets hot water in the CH pipework. The first can be cleared by flushing backwards through the system with mains pressure water. The second is best cured by cutting out the sacled-up connection and re-making it or clearing it manually, but if that's not possible then something like Kilrock or one of the proprietary CH system descalers will open it up over a period of time. To get the system going it can be filled from another point in the pipework (self-cutting washing machine valves are good for this). Make sure the way to the vent pipe is open and clear, though, or there will be real danger of explosion.