Potterton HE Plus humming noise

[john2k]

My potterton he plus combined boiler is about 6/7 years old and recently when the central heating is on for a while the boiler would randomly start making a rather loud humming noise. It's not a metallic noise just a humming noise like noise pump or fan kind of noise. A bit like an example of a car on low rpm noise vs a slight higher rpm. It's as if something is working extra hard.

Any ideas what this can be?

Also I topped up the pressure to halfway mark of the green zone. When boiler warms up it goes right to the border line of the green zone. Is that amount of pressure increase normal?

 

[rpm]

As it was recently repaired by Baxi why not call them back?

 

[jonnyswamp]

Pressure rise is normal and without hearing noise, can't comment, but could be boiler modulating down once set temp is reached and just happily chugging away

 

[Dotty]

Either call Baxi back or an independent gsr.

I'm afraid that's all the advice we can give you.

Job 38.11.