Loss of pressure in unvented central heating system.

[kristy22]

New Valiant ecoplus 438 wall hung condensing boiler. Hot water cylinder, on first floor. Pressure vessel in loft, Pressure drops in vessel approx 1 bar per day. Does not appear to be due to pressure relief valve. No leaks apparent. System has been running for 3 months and is a combination of old pipework in house and new in extension. Any suggestions as to cause of pressure drop please,

 

[Dan]

Welcome to Plumbing Forum | Plumbing Advice | Plumbers Forums | A forum for plumbers advice in the UK!

Welcome to UKPlumbersForums.co.uk kristy22. Thanks for introducing yourself.

 

[Billy Bob Bob]

you either have a leak somewhere in the house or a faulty expansion vessel,it does not take much of a leak to drop pressure in a sealed system,are things like your rad valves up to it?are they 10 bar?

 

[oldplumber]

if I ran my system at 10 bar everything would give upwhy do rads valves have to be 10 bar? max I want to work at is 1-21/2 serious question here not sarcasm

 

[Billy Bob Bob]

if I ran my system at 10 bar everything would give upwhy do rads valves have to be 10 bar? max I want to work at is 1-21/2 serious question here not sarcasm

dont know,i advise everybody to fill there boilers to 1 bar when cold especially if its a he boiler,they say rad valves are built to 10 bar to cope with pressurised systems

 

[kristy22]

Thank you so much Gasman for this usual info. It is all a nightmare at the mo!! Appreciate your expertise.