To identify the type of boiler you have, there’s a couple of things to check. If you’ve found a water tank around the house then you’ve got a heat-only or system boiler, whereas if you don’t have a water tank then you’ve definitely got a combi boiler. The majority of homes in the UK make use of a combi boiler (so don’t be concerned if you can’t find a hot water tank!). Keep in mind that should the time come where you need to replace the boiler, it’s generally cheaper to replace a boiler with the same type rather than fit a different type of boiler. Once you’ve found the boiler and you have the maintenance records, you can carry out your own inspection to check for the following:
- Unpleasant smells around the boiler – burnt plastic smells could be a sign of overheating whilst an eggy smell is a sign of a gas leak.
- A puddle below the boiler or dripping water – a leaking boiler needs immediate attention.
- Unusually high energy costs when the weather hasn’t gotten colder – if the boiler becomes less efficient, it’s usually sign that it needs urgent maintenance. Refer to the boiler energy label as this will give you an idea of the expected costs.
- Unexpected noises around the boiler – whilst all boilers make a little noise, this should be a continuous hum instead of a knocking / whistling / banging sound, these should all be checked by an engineer as soon as possible.
Having checked the boiler itself, the next thing to check is the rest of the heating system – the radiators (and water tank if you have one).
Naturally, the very first thing to check with the radiators is to ensure that they all work. By turning the boiler on and giving the radiators a chance to heat up, you’ll be able to see very quickly whether or not each of the radiators turn on. If the bottom of the radiator is warm but not the top, this isn’t a cause for concern because most likely you’ll just need to bleed it and let some trapped air out of the system. The elements to focus on are the age of the radiator itself but this can be hard to establish from an initial glance – generally a radiator will need to be replaced after 15 to 20 years as they will suffer from a build-up of corrosion and limescale which will reduce effectiveness. As long as you can’t see any signs of rust or leakage, and you can’t feel any cold patches (once you’ve bled the system) then the radiator should be good to go! Whilst not necessarily a deal-breaker, it’s worth looking for additional features such as thermostatic valves as they allow you to manually change the amount of heat produced by each radiator in the system.
These same considerations should be applied to the water tank (where applicable), if there is no signs of rust or leakage then there should be no reason for concern. As useful as a visual examination is, due to the nature of heating systems almost all of the system is out of sight so it’s always worth getting a heating engineer to give the system a thorough check unless the previous homeowner has an up-to-date service record!