Boiler pressure issue

[Craig26]

Hi all looking for some help with my boiler.

The pressure when cold sits around 0.8 to 1 bar but when the heating is on this is rising to near 3 bar on the gauge. I've had the expansion vessel re charged as it was reading 0 bar topped up to 1 bar but when releasing the pump from the valve water was coming out of the valve. Would this indicate that the expansion vessel has failed? The boiler is a viessmann vitodens 050-w

Still getting hot water and radiators but don't want to cause any further issues so keeping heating off.

 

[SJB060685]

Sounds like the diaphragm has failed. Will need a replacement expansion vessel and a gas engineer to repair.

 

[Scott_D]

Is it under warranty?

 

[Craig26]

Sounds like the diaphragm has failed. Will need a replacement expansion vessel and a gas engineer to repair.

Thank you for the information thought it might be going to get a replacement tomorrow and hopefully get the gas safe engineer in to fit this week

 

[Stu-B]

New expansion vessel required

 

[Craig26]

Is it under warranty?

Just out of warranty!

 

[townfanjon]

The valves are on the bottom of the vessels, not a good idea because its where the condensation ends up , theres always some water comes out , but obviously I dont know how much came out . The valve wants removing and all the water drained out and then recharging. There is something else it maybe , but I cant go into this , your engineer should have an idea what to check next

Edit , sorry ignore valve on the bottom , I was thinking 100 . 050’s are on the top.

 

[Craig26]

The valves are on the bottom of the vessels, not a good idea because its where the condensation ends up , theres always some water comes out , but obviously I dont know how much came out . The valve wants removing and all the water drained out and then recharging. There is something else it maybe , but I cant go into this , your engineer should have an idea what to check next

Engineer came out Friday drained the system topped up the vessel and when I tried the heating the same thing happened so hoping that replacing the expansion vessel sorts it. The boiler is just over 5yr old