Boiler loosing pressure

[Ruthd]

Hi,

I have a ravenheat csi85 t combi boiler which is slowly loosing pressure. When cold the pressure is around 1, when hot it goes up to 2.5. There is a small trickle of water from the pressure relief outflow. There is also a small amount of water coming from the auto-air vent. I assume I need to check the expansion vessel and change the prv valve but not sure why water is coming from the auto-air vent. I have recently spent money on the boiler and had it 'serviced' and I'm annoyed that the engineer hasn't actually serviced it at all! Any advice would be great.

Thanks

 

[wannocks]

If was done recently I'd get them back. Checking and recharging an expansion vessel is part of a service. The PRV may need replacing. If not get someone else out to do it.

 

[Storms]

If was done recently I'd get them back. Checking and recharging an expansion vessel is part of a service. The PRV may need replacing. If not get someone else out to do it.

Just out of curiosity do you charge a expansion vessel with a normal pump (with an attached gauge ) or do you use a specific plumbers tool?

 

[Ruthd]

Thanks for the prompt reply. What would cause water to come out of the auto-air vent and should I get it replaced?

 

[petit_pablo]

Thanks for the prompt reply. What would cause water to come out of the auto-air vent and should I get it replaced?

The float inside will be crudded up so it doesnt close off properly and yes the AAV will need replacing.