Winter is on its way and it can say with some certainty that all of us are thinking back to last year and what condition our boilers are in. Although most honest plumbers will recommend that you get your boiler serviced every season, some of us still have enough faith in our technical knowhow and declare the boiler fit on the evidence of it being in perfect shape at the end of last season.
In the recent past the UK has experienced very harsh winters with the temperature plummeting as low as -20 c. This has necessitated extra caution when preparing your boiler for the winter.
Condensing in high efficiency boilers has been quite common in this harsh weather. This happens when the condensate drainage pipe freezes and gets blocked with ice. In the vast majority of cases this occurs when the condensate drainage pipe is located externally for part or whole of its length. British regulations allow condensate drainage pipes to be located externally for some part of its length. Perhaps this regulation needs to be looked at again to reduce the possibility of frozen condensate pipe. In the meantime however, we need to be better informed when it comes to installing boilers and make sure they are installed in such a way that there is minimum possibility of frozen condensate pipes. It has to be said here that even the best tended boiler will not function properly if it has a frozen condensate pipe problem.
The signal that there is a frozen condensate pipe problem is your boiler display showing a fault code and the physical signs are a gurgling noise from the main boiler body. A condensate pipe carries condensation from your boiler to the outside drain; it is usually a white or grey plastic pipe travelling from your boiler, through the external wall and into your outside drain. During cold weather the condensation in this pipe can freeze making the condensate back up and shut the boiler down.
If there is a suspicion that you have a frozen condensate pipe issue the first thing to do is to confirm that this indeed is the problem. As explained earlier this can be done by looking out for a fault sign on the boiler display and/or listen for gurgling noise from the boiler. Then the fault point should be located which will invariably be at the most exposed part of the pipe, it can be located by running your fingers over the condensate pipe, the coldest part will be the problem spot and can help in identifying the blockage. The next step is to thaw the pipe by pouring hot water over the identified section. Boiling water should not be used as it can crack or damage the frozen condensate pipe. After making sure that the frozen condensate pipe has been thawed the boiler should be restarted, consulting resetting instructions on the boiler manual is a good idea when restarting.