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Plumberpro, Mechanical Engineer
Category: HVAC
Satisfied Customers: 634
Experience:  Over 20 years experience in plumbing heating and gas
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Our Remeha Avanta 28C boiler is having pressure issues. We

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Our Remeha Avanta 28C boiler is having pressure issues. We have had to top up the pressure to 2 bar on a number of occasions after it dropped to 0, and now the pressure is constantly 3 to 4 bar, which I imagine is not good for it. Any advice, please?
Your expansion vessel in your boiler is either flat or split.
As the water gets heated it expands. This expanded water to pushes into the expansion vessel which has a balloon inside. If this goes flat or splits the water has nowhere to go and will go up to three bar and dump out of the safety valve( preset at 3bar to release).
Take the cover off the boiler ,with power off . drop the pressure to zero( release water from a rad bleed valve into a lot) then unscrew he exp vessel cap( like a car tyre cap) and pump it up with a car foot pump to 1.5 bar . refill the system to 1.2-1.5 .should run normally. If it still happens replace the vessel
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