leak in central heating

3 Jan 2010
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United Kingdom
every morning I have to top up my central heating as the gauge indicates that it is empty, I assume there is a leak somewere. I was going to try a central heating leak sealer like Fernox F4. Wondered if anyone had any experience with it?

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Not necessarily. Do you see water anywhere?

It could be down to the expansion vessel or the pressure relief valve. Do you have an expansion vessel on the pipework? If you do, then there will be a valve like on a car tyre. Press that and see if any water comes out. If there is water present then it will need replacing. If the vessel is inside the boiler then you should get somebody qualified to have a look.

It could also the the pressure relief valve letting by. There should be a pipe connected to valve discharging outside somewhere. Put a bucket or tie a bag underneath and see if it collects water after you topped up the system. If it is this then it should be investigated further by someone qualified.

If its neither then get someone qualified to take a look.

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