If your boiler is getting older and has started to let you down, it is natural to wonder whether to keep paying for repairs or put the money towards a new one. As a rule, a one-off fault on a boiler under about 10 years old is usually worth repairing. An older boiler that breaks down often, needs an expensive part or costs more and more to run is often better replaced.
This post explains how to weigh up age, repair costs, running costs and safety, and what an engineer looks at before giving advice. You can make a few simple checks yourself, but never remove the boiler casing or touch any gas parts. Work inside a gas boiler is only ever a job for a Gas Safe registered engineer.
How long a boiler usually lasts
A good-quality boiler that is serviced every year should last around 10 to 15 years. That is the range Worcester Bosch gives for its own boilers, and a fair guide for most makes.
Age on its own is not a reason to replace a boiler that is safe and working well. But as a boiler gets older, parts wear out, faults come more often and the manufacturer's warranty has usually ended, so every repair comes out of your own pocket.
You can usually find your boiler's age on the installation certificate or your last service record. The model and serial number are also printed on the data badge, a small label often found on the underside of the boiler.
When a repair is usually the sensible choice
A repair usually makes sense when:
- the boiler is under about 10 years old
- it is the first real fault in years
- the part is easy to get and the fault can be fixed in one or two visits
- the boiler is still under the manufacturer's warranty, which may cover the part
Many common faults are routine repairs. A failed pump, a sticking diverter valve (the valve in a combi boiler that switches between heating and hot water) or a worn pressure relief valve can all be replaced, and fixing them can give a sound boiler several more good years.
Signs it may be time to replace your boiler
It is worth getting a replacement price alongside the repair quote if:
- it has needed more than one call-out in the last year or two
- the repair is a big share of the cost of a new boiler, such as a new heat exchanger (the part that passes heat from the burner into the water) or a main circuit board
- parts are getting hard to find because the model is no longer made
- it is noisy, slow to heat up or keeps losing pressure even after repairs
- your gas bills have crept up with no change in how you use the heating
- it is an old non-condensing boiler, which you can often spot because there is no plastic condensate pipe running from it to a drain
One sign on its own is rarely enough. Two or three together usually mean an old boiler is costing more than it is worth.
How running costs come into it
Since April 2018, every gas boiler fitted in an existing home in England must be at least 92% efficient, under the government's Boiler Plus rules. It must also come with a timer and room thermostat, and a new combi needs one extra energy-saving feature, such as smart controls or weather compensation (controls that adjust the boiler to the temperature outside).
Older boilers, especially non-condensing ones, can be much less efficient than that. A modern boiler with good controls burns less gas to keep your home as warm. How much you would save depends on your old boiler, your home and how you use the heating.
Safety comes before cost
Some problems are not a repair-or-replace question. Gas Safe Register lists these warning signs of an unsafe gas appliance:
- a lazy yellow or orange flame instead of a crisp blue one
- a pilot light that keeps going out
- dark marks or staining on or around the boiler
- more condensation than usual on the inside of windows
If you notice any of these, or your carbon monoxide alarm goes off, turn the boiler off, open windows and get a Gas Safe registered engineer to check it before you use it again.
If you smell gas, open doors and windows, turn off the gas at the meter if you can do so safely, do not use electrical switches or naked flames, and call the National Gas Emergency number on 0800 111 999 straight away.
Is a heat pump worth considering?
If you are replacing a boiler anyway, an air source heat pump is another option. The government's Boiler Upgrade Scheme currently gives £7,500 towards an air source heat pump for homeowners in England and Wales who are replacing a fossil fuel heating system, as long as the installer is MCS certified. It does not cover a like-for-like boiler swap.
A heat pump works best in a well-insulated home and may need some larger radiators, so it is not right for every house. You can read more on our air source heat pumps page.
What we look at before giving advice
When Pegasus Plumbers is called out to an older boiler, we find the fault first and make sure the boiler is safe. We carry common parts, so many repairs can be finished on the first visit. If the boiler is near the end of its life, we give you a clear report with the repair and replacement options side by side, so the choice is yours. As one customer put it: "At all times it was clear that the essential repairs could be completed but we decided to go ahead with an upgrade."
If you decide to replace, we survey your home first, checking the pipework, your hot water needs and how much heat the house loses, before recommending a correctly sized boiler. Whichever you choose, a yearly service helps any boiler last longer, and our boiler service checklist explains what that involves.
If your boiler is getting on and you are not sure it is worth fixing, Pegasus Plumbers can take a look and talk you through both options before winter sets in. Book a boiler repair visit for a fault, or ask about boiler installation if you would like a replacement price for your home in Romsey or the surrounding villages.
