firebird heatpac suddenly loses pressure

[muso58]

Hi all i fitted a heatpac recently all seemed well until one day pressure dropped to zero .Now if i charge it ,it can stay constant for weeks ,then suddenlt loses all pressure ,not gradually ,basically it can go from 1.5bar to zero overnight. No visible leaks checked exp vessel pressure .
Also get gurglling sound when i select hot water . Any ideas ?
Thanks for looking

 

[dilalio]

Hi all i fitted a heatpac recently all seemed well until one day pressure dropped to zero .Now if i charge it ,it can stay constant for weeks ,then suddenlt loses all pressure ,not gradually ,basically it can go from 1.5bar to zero overnight. No visible leaks checked exp vessel pressure .
Also get gurglling sound when i select hot water . Any ideas ?
Thanks for looking

Discharge from PRV?
All air purged from system?

 

[muso58]

Took boiler up to 2.5bar found a tiny leak on heating circuit connector on bolier repaired that . Seems to be holding 1.5 bar now .I still have air getting into highest rad though.
Every day i get about 1seconds worth of air out of it . Ive gone thru all other rads and no air in them .
How can air get into the circuit when its at a constant pressure well over 1 bar ?
Surely if there was a breach somewhere it would lose water but not be able to suck air in!
Im obviously missing something ,would really appreciate any pearls of wisdom .Thanks guys

 

[dilalio]

Hydrogen or air working it's way to the surface.