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No seems to be ok with just heating on, just when a hot tap is used the pressure quickly decreases and heating water comes out of tapTime to get a gas engineer sorry to say sounds like the exchanger has gone heating side
Does the boiler over pressurise ?
Ye, time to get the professionals in, thanksThat is probably because the heating system is at a very similar pressure to the mains. So with no hot tap open the system is fairly stable; but as soon as a hot top is opened the pressure on that side of the heat exchanger drops and this allows the heating system water to cross into the hot water system and de-pressurise the heating system. It sounds like Shaun has got the answer for you.
No, solid link filling, both taps off, thanksFilling method taps open?
Reply to the thread, titled "Heating water from hot tap" which is posted in UK Plumbers Forums on Plumbers Forums.
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