We have a Worcester Bosch Greenstar 34 CDI Classic installed in 2015 and regularly serviced since. We have an ongoing but intermittent problem that the gas engineers seems incapable of resolving and I am hoping maybe someone can offer some thoughts before we incur more expense.
The issue is a very loud rumbling / vibration that generally happens only when the heating is on. It has happened when just the hot water is being called for but nearly always it seems to involve the heating. When the problem arises it's as if the boiler is unable to provide heat and is trying to build up into heat mode but cannot quite get there. Then, as it comes off this peak of activity it makes the rumbling noise which is very loud and can be heard throughout the bungalow. The noise is always accompanied by much gurgling and glugging in the boiler.
Generally we turn the thermostat down (i.e. remove the call for heat), leave it for some while and then it will usually be ok. Once it is running ok then there is no problem at all with the boiler. In the past British Gas have suggested we look at the condensate pipe to check all is well; this we have done and (as far as we can tell) it appears to be ok. Certainly the issue is not being caused by the pipe freezing as the problem arises regardless of the temperature outside. We can go several days without it happening and we cannot identify anything we do that might trigger the problem. We have shown videos to service engineers but it never seems to happen when they are here and so far they have failed to establish what the issue is.
Any thoughts much appreciated.
The issue is a very loud rumbling / vibration that generally happens only when the heating is on. It has happened when just the hot water is being called for but nearly always it seems to involve the heating. When the problem arises it's as if the boiler is unable to provide heat and is trying to build up into heat mode but cannot quite get there. Then, as it comes off this peak of activity it makes the rumbling noise which is very loud and can be heard throughout the bungalow. The noise is always accompanied by much gurgling and glugging in the boiler.
Generally we turn the thermostat down (i.e. remove the call for heat), leave it for some while and then it will usually be ok. Once it is running ok then there is no problem at all with the boiler. In the past British Gas have suggested we look at the condensate pipe to check all is well; this we have done and (as far as we can tell) it appears to be ok. Certainly the issue is not being caused by the pipe freezing as the problem arises regardless of the temperature outside. We can go several days without it happening and we cannot identify anything we do that might trigger the problem. We have shown videos to service engineers but it never seems to happen when they are here and so far they have failed to establish what the issue is.
Any thoughts much appreciated.