Pressure problem. gloworm swiftflow 80 combi boiler

[LAGASTRANTHA]

I have a gloworm swiftflow 80 combi boiler,
Recently the pressure gauge rises to 3.5bar (usually .7-1.4) when heating is on, this is then bringing in the pressure release valve automatically & discharging. I then have to top up. Could this be as simple as the water pressure switch having failed, as it is nine yrs old. When the heating is off the boiler holds it's pressure at .7 bar.

 

[CH4]

It is most likely to be a problem with the expansion vessel.

For more information please see the pdf document HERE, or search these forums (there have been many posts concerning expansion vessels).

 

[LAGASTRANTHA]

It is most likely to be a problem with the expansion vessel.

For more information please see the pdf document HERE, or search these forums (there have been many posts concerning expansion vessels).

Thanks for that, I shall call an engineer.

 

[LAGASTRANTHA]

It is most likely to be a problem with the expansion vessel.

For more information please see the pdf document HERE, or search these forums (there have been many posts concerning expansion vessels).

Thanks for that, I shall call an engineer.

 

[LAGASTRANTHA]

It is most likely to be a problem with the expansion vessel.

For more information please see the pdf document HERE, or search these forums (there have been many posts concerning expansion vessels).

Thanks for that, I shall call an engineer.

 

[LAGASTRANTHA]

It is most likely to be a problem with the expansion vessel.

For more information please see the pdf document HERE, or search these forums (there have been many posts concerning expansion vessels).

Thanks for that, I shall call an engineer.