We have an Ultracom 35Cxi combi boiler which is just over three years old. Earlier this year we had two radiators replaced and the system cleaned. Following the radiator replacement a loud vibrating noise started coming from within the boiler during central heating start up.
The noise starts around 5 minutes after the boiler starts and then continues for around 10 minutes, then stops and the boiler works fine for most of the day while on a timer. We have no problems with the hot water. The problem does not happen when it is relatively mild and is apparently worse the colder it gets.
Glow worm have been out, serviced the boiler and say there is not a boiler problem, that it is air in the system. The plumber who fitted the radiators say it's a pump problem. I have of course bled the radiators (releasing a small amount of air in one radiator) but this doesn't seem to help.
Any advice gratefully received!
The noise starts around 5 minutes after the boiler starts and then continues for around 10 minutes, then stops and the boiler works fine for most of the day while on a timer. We have no problems with the hot water. The problem does not happen when it is relatively mild and is apparently worse the colder it gets.
Glow worm have been out, serviced the boiler and say there is not a boiler problem, that it is air in the system. The plumber who fitted the radiators say it's a pump problem. I have of course bled the radiators (releasing a small amount of air in one radiator) but this doesn't seem to help.
Any advice gratefully received!
