Subscriber OnlyProperty Clinic

Our new new combi-boiler breaks down every night. What can we do?

We have to manually switch our boiler on to heat our home or have a shower

We installed a combi-boiler in summer 2022 and it worked well for over a year until the start of the new heating season last October. That coincided with our kitchen upgrade last summer, so we engaged with our plumbing contractor on that work as well as the original gas installer. Neither could pinpoint a cause of our problem, which manifested as the boiler working during the day but cutting out at night due to a sudden drop in pressure. This means we cannot put on our central heating for an hour before bedtime or set it to go on an hour before we get up. Instead, we have to manually switch the boiler on early each morning to start our central heating and have showers.

Given that the pressure in our boiler is related to that in the water mains, we contacted Uisce Éireann several times and asked if they were reducing water pressure in our area during night-time hours, probably to lower leaking from old mains. They have never answered that question, nor have they given an answer to our local councillor whom we asked also. We would be very grateful for any information or help you can offer us.

Queries of this nature are normally for a mechanical and electrical consultant. As building surveyors, we are a bit like a GP, patients attend with issues which we can diagnose and advise on, but regularly issues of a specialist nature will arise which need to be referred on to the appropriate specialist. The mechanical and electrical services within a home tend to be specialist areas, and while building surveyors have a working knowledge of these elements, there is a very high reliance placed on the expertise of the designers and installers of mechanical and electrical installations.

The heating system is one such area and in particular the boiler and the workings of same requires a high degree of specialist knowledge. If people come to us with issues similar to yours more often than not, they will be referred on to a registered gas installer or a mechanical and electrical consultant.


That said we can comment broadly on these types of situation. The first issue here is that the boiler is relatively new, and it is reasonable to expect that a warranty would have been provided with it. It would be necessary to have full details on this before proceeding further. If the boiler is still under warranty, then you will need go through a certain process in order to ensure that the warranty is not in any way invalidated. That said very often domestic boilers will only have a one-year warranty and thus you may well be outside the warranty period already. It’s essential to be aware of the warranty status before bringing in any other third parties to review the situation.

Secondly even if the warranty has expired, there is a reasonable expectation that a reputable contractor will have pride in their work and indeed their reputation, and the original installer should be consulted and asked to provide an opinion as to what the issue is here.

You point out that you engaged the original installer and the plumber involved to work on your recent kitchen upgrade. Although both are specialists in this area, neither are in a position to pinpoint the problem. This indicates that the problem here is either particularly complex or may simply be an attempt to cover up flawed work that has already been carried out. Although we consider the latter unlikely, all options do need to be explored and thus there may be merit in bringing in an independent boiler specialist to review the matter at this stage.

The symptoms that you describe are arising from a drop off in pressure that is either as a result of the reduced water supply to the boiler, or alternatively is as a result of leaks within the heating installation. You were right to contact Uisce Éireann and it is disappointing that they have failed to respond to your query; this is very poor from a customer-service perspective, and you are right to call them out on it. At the very least, one would expect a simple acknowledgment of your query, noting that the matter is being reviewed or an explanation as to why an answer cannot be provided to the question.

If your boiler is constantly cutting out it will have an impact on the long-term performance of the boiler and ultimately reduce its “life expectancy”. We would further caution that if there is a leak emanating from the system, this could be giving rise to unseen damage such as behind walls or underneath the floor.

It is essential that this problem be addressed as a matter of urgency. Your primary requirement will be to bring in either a registered gas installer or a mechanical and electrical consultant who should be able to trace and identify the exact problem. While it should be possible for you to work directly with the specialist, there may be merit in also bringing in a chartered building surveyor to help you in planning and co-ordinating the works, in interpreting the issue and advising on a holistic solution to the problem. In this way, you will get a team approach to resolving the problem.

Val O’Brien is a chartered building surveyor and member of the Society of Chartered Surveyors Ireland.

Do you have a query? Email

This column is a readers’ service. The content of the Property Clinic is provided for general information only. It is not intended as advice on which readers should rely. Professional or specialist advice should be obtained before persons take or refrain from any action on the basis of the content. The Irish Times and it contributors will not be liable for any loss or damage arising from reliance on any content