Why it’s important to get your combi boiler inspected

Mar 1, 2022 | Inspections

If you’re buying a “new home”, many people will want to know about structural issues or damage – presuming this will be their biggest outlay either immediately or down the line. However, homeowners regularly overlook one of the most important areas of a home, the plumbing!

Updating plumbing has become increasingly popular in recent years, with many people opting for a combination boiler, also known as a combi.

Combis have become the ‘go to’ option due to their simple and space-saving design – they take hot water directly to your taps with no large, unsightly storage tank to be seen. However, that also means you no longer have an “airing cupboard”.

A combi boiler operates using condensing technology when a sensor detects that you have ordered water. Condensing technology refers to a boiler’s ability to collect waste heat from its own exhaust fumes in order to reduce fuel consumption. The heating unit then uses fuel (gas, electricity or oil to operate the system) to burn until the water is heated to the desired temperature.

With the ability to access hot water at the turn of a tap, combis gradually became a must-have in many recent homes since their introduction in the 1970s. Combined with their size which made it easy to have even in the smallest of properties, combis are regarded as the most cost-effective boiler, saving you money as you use hot water as and when, opposed to constantly heating a tankful to temperature, and then using more fuel to keep that hot.

While combi boilers can be a great option for some, they aren’t 100 per cent fool proof. They have an overly complex system, with lots of different devices working together to create the heating to radiators or hot water. As a result, they can be expensive. They can also take longer to fix should anything go wrong – as they have so many little parts, valves, printed circuit boards and even the pump is inside the boiler unit.

As combi boilers are an on-demand service, multiple outputs aren’t always easy to accommodate. If two or more people need access to hot water at one point, you will notice water pressure drop and if you have a large household this could become an issue. But a combi may struggle to provide a good flow of hot water to shower or bath taps in cold weather, as it has to bring almost freezing cold mains water up to the temperature you want.

Increasingly, properties also have not only a combi boiler but an additional Pressurised Water System. This means that you have a tank that can produce hot water without needing a second tank in the loft to feed water through using gravity.

With benefits such as making it easier to have a power shower and baths fill quicker, a Pressurised Water System can be great to have on hand to work in partnership with a combi boiler, balancing out any issues you may have from a combi. This includes low water pressure, mentioned above.

However, adding a Pressurised Water System can make your plumbing system more complex and due to the nature of the combi boiler, you shouldn’t need an additional tank unless you have a particularly large household. When buying your next home, a surveyor conducting a RICS Homebuyer Survey will not check your boiler’s particulars as this needs to be conducted by a qualified “Gas-Safe” registered engineer. What a surveyor will do, is visually inspect the boiler and attendant fittings, then advise that it should be checked and that the potential new homeowners gain access to the most recent service information as they MUST be serviced every year by a professional.

If you are not sure if you have a combi with a Pressurised Water System attached, this will be easy to find out as it will be a white, red or blue, almost onion-shaped tank, attached to the boiler via the pipes, or next to the hot water cylinder. Your surveyor will take note of this addition to add to their survey.

It’s important to note that having a water tank attached does make the plumbing technically more complex than a standard boiler and more can go wrong with them. Annual servicing is even more important in this instance.

I personally highlight combi boilers with Pressurised Water Systems as a ‘Condition Rating 3’ in all my surveys. As standard, I will comment that they need annual servicing by a ‘competent person’, including testing of safety valves, recharging pressure vessels, cleaning, pressure reduction valves and providing a service certificate.

It would also then be beneficial to have an appropriately qualified person to inspect the boiler and the tank to report on its installation prior to purchase. This will help to prevent any nasty surprises when you move in.

If you’re unsure if you’ve taken the appropriate steps or any issues arise, speak to your solicitor, to request any paperwork about such work, before you sign or exchange contracts.

If the boiler hasn’t been serviced within the last 12 months, make sure a system test and service is undertaken prior to buying the property as this could be problematic for you, and expensive to put right. Even more so if you have a combi with a Pressurised Water System.

Les Long FRICS FISVA Principal, Eyesurvey

Contact EYESURVEY Chartered Surveyors here for all your professional property services and needs.