Boiler pressure

[James Bowtell]

Hi everyone,

My boiler pressure is driving me mad. When the boiler is on the pressure gauge slowly drops from 1.5 bar to 0.8. When I turn the boiler off or the timer shuts off the central heating the pressure gauge shoots back up to 1.5. Do I have a leak or a dodgy pressure gauge or potentially something else wrong.

Thanks

 

[mcmoby69]

Pressure sensor will be affected depending on which side of the pump it is on.
That amount of difference you have could indicate a problem with the expansion vessel.

You may need an rgi, what boiler do you have?

 

[dilalio]

Hi everyone,

My boiler pressure is driving me mad. When the boiler is on the pressure gauge slowly drops from 1.5 bar to 0.8. When I turn the boiler off or the timer shuts off the central heating the pressure gauge shoots back up to 1.5. Do I have a leak or a dodgy pressure gauge or potentially something else wrong.

Thanks

Describe your system more...

 

[James Bowtell]

It's a baxi main eco elite combi boiler. I've bled all the radiators and also checked for lead but nothing. Nothing coming from the PRV

 

[James Bowtell]

Leak not lead

 

[dilalio]

If all else works and just the gauge playing up then suspect faulty gauge or ev issues, before looking further.

 

[mcmoby69]

Not familiar with that model, but are you getting a pressure related fault code?

Pressure will fluctuate when the boiler heats up or cools down, when the pump starts or stops etc.

No faults means stop watching the boiler, watch TV instead.

 

[James Bowtell]

I'm getting the E19 pressure low warning

 

[mcmoby69]

if you bled the radiators, did you top it back up again.

read the faq's at the top of the plumbing forum

 

[James Bowtell]

Yes topped the boiler backup. The boiler then drops pressure when on, then the lost pressure shoots backup when the timer turns off the boiler or I manually turn the boiler off. If I leave the boiler on for 10hours, the pressure is so low it stops and errors E119 low pressure.