losing pressure?

[queend]

New Valliant Boiler fitted recently. Developed a problem with losing pressure soon after fitting and it has gradually got worse. We recently switched on the heating and now we lose the pressure completely over a 48 period. Engineer has checked for leaks and there are none, he has now put in the leak seal solution into the system but within hours after leaving we started to lose the pressure. Today we switched off the central heating but are still using the boiler to heat the hot water. We are still losing pressure.
Is there any other reason why we are losing pressure if we do not have a leak?

 

[Billy Bob Bob]

were your rad valves replaced on your existing system?

 

[queend]

No, I don't think so

 

[Billy Bob Bob]

could be your problem leaking trough the glands on normal rad valves (not trvs)pull the plastic tops off any water/crud/corrosion on the gland there's your problem

 

[everflow09]

check if PRV is not dicharging outside?

 

[queend]

Sorry probably should know but don't - what is a TRVS
and
if we do find any of the water/crud/corrosion - is the answer to replace the valves?
Thanks

 

[queend]

Thanks for that - I will get that checked out

 

[Billy Bob Bob]

check if PRV is not dicharging outside?

could be a faulty expansion vessel but i am making a presumption that was checked

 

[queend]

Perhaps it wasn't - I will double check that with the Engineer who will have to come back out.
Thanks for being so helpful - just wondered if we are only heating hot water and not the radiators but still losing pressure, does that rule out a leak within the radiator pipework?

 

[Billy Bob Bob]

Perhaps it wasn't - I will double check that with the Engineer who will have to come back out.
Thanks for being so helpful - just wondered if we are only heating hot water and not the radiators but still losing pressure, does that rule out a leak within the radiator pipework?

no as you now have a pressurised system all associated pipework,valves etc comes into question,and if you do find problems with the valves then yes they need replacing btw trvs > thermostatic radiator valves