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Plumbing

Loss of pressure

Anonymous user 16/03/2024 - 2.45 PM

We have recently had installed a new Worcester Bosch 18/25 oil fired combi boiler to replace our old model. Its location has required new pipework to connect to the rest of the system, but that is the only change. We keep losing pressure now, previously the heating system held pressure. I have searched as much of the pipework as I can and cannot find any leaks, so I added Fernox F4 to the system. The pressure held, but now has started dropping again, quite rapidly. The WB engineer said there were no leaks in the boiler so I am at a loss and any help would be appreciated as to where to go from here.

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5 Answers

Anonymous user

Have you checked outside to see if the pressure relief valve has been letting off as it can be this that is faulty but without coming out to assess the system would be hard to tell.
Answered2 February 2022
0

Stow Plumbing Services

Rating: 5 out of 5
Gloucester
Although the boiler is new there may be a fault with the expansion vessel, the diaphragm may be perforated or may just need recharging, the engineer/company that did the work should be able to check this if they haven't already.
Answered2 February 2022
0

D & R Property and Plumbing Maintenance

Rating: 4.9 out of 5
New Romney
what boiler did it replace ie a combi, a heat only boiler, an open vented boiler ?,it could be there is not enough expansion capacity in the new boiler, consult worcester bosch, explaining to them how big your central heating system is.
Answered2 February 2022
0

DS Gas Services

Rating: 5 out of 5
Bridlington
With the boiler being new it would be unlikely that the pressure relief valve or the expansion vessel would be failing although not impossible. I think it’s more likely that you do not have enough inhibitor in your system and that would mean you have active corrosion. Which would create what you think is air but intact it’s Hydrogen. Hydrogen is a product of oxidization (rust) in the system. As the hydrogen passing through the auto air vent it would release and that would cause the pressure to drop.
Answered2 February 2022
0

Anonymous user

i could be the pressure relief vale. If you have your PRV replaced with a new one and it continues to leak, you may have a problem with the boiler's internal expansion vessel.
Answered3 February 2022
0