My GF boiler unit - a floor stander, approx 17 years old - makes a vibrating noise when the burner isn't producing DHW or heating the radiators. It is a fairly quiet noise, from low down at the rear, and I think it is roughly at 8Hz. Sounds to me like a low speed motor running, which I guess must be the pump (after all, what else would there be in a GFCH boiler unit).
If it is the pump, why should this be running when no heat is being put into the water (and hasnt been for even half a day)? If it isn't the pump, what could it be? And should I be concerned by any of this please?
Appreciate any advice
If it is the pump, why should this be running when no heat is being put into the water (and hasnt been for even half a day)? If it isn't the pump, what could it be? And should I be concerned by any of this please?
Appreciate any advice