Hi , pressure drops to 0 when the system is cooling down. Holds pressure while running though, and I need to top back to 1 daily when system is cold. Thermocouple ? and pressure release valve changed, no visible leaks? any ideas please

dispair, January 2013

Thank you , so this may be the answer ,I hope
thank you for replying

despair, January 2013

expansion vessel needs inflating. its a red tank inside the boiler . drain the boiler down to 0 bar then get a car tyre foot pump and inflate the nozzle on the tank to 1.5 bar then just refil the boiler and it should be fine. if it goes down again after a while the expasion tank may need replacing

kash, January 2013