Hi.

I have a Worcester Bosch oil fired boiler about 6 years old. During the
winter only the selenoid valve on the oil inlet chatters and makes a
helluva noise. In the warmer weather it is as quiet as a lamb. I live
in a country area and suspect that the mains voltage is dropping due to
more load on the overhead cables that feed our village. How can I check
and is there a statutary voltage that the supplier must meet?