Boiler Maintenance (and how to buy a new one)
New homes already have energy-efficient boilers. But many older draughty homes have old boilers that are past their best. Of course the main issue is that new boilers are very expensive, so some people just keep old boilers regularly serviced, until they give up the ghost.
A boiler keeps your home warm and provides hot water, so is one of the most important appliances. When it runs well, it keeps you comfortable. But when it’s old and not working right, it can not only cause higher bills, but even safety issues.
Also read our posts on affordable home insulation and radiator boosters.
Get an annual boiler check. iHeat offers local Gas Safe registered engineers, who can do this for around £99.
Only hire Gas Safe Registered engineers
When it comes to boiler servicing or repairs, only a Gas Safe registered engineer should handle the job. They have the right training, skills, and legal permission to work safely with gas appliances. Using anyone else not only risks your safety but can also break the law and might invalidate your insurance.
Before booking an engineer, check their Gas Safe Register ID card. It shows their registration number, expiry date, and the type of gas work they’re qualified for.
Boiler care is a mix of light checks at home and one proper annual visit from a qualified engineer. That split matters, because some jobs are safe for you, and some really aren’t.
Simple checks to do at home
- First, look at the boiler pressure gauge. Many systems work best around 1 to 1.5 bar when cold, but check your manual because models differ. If pressure keeps dropping, don’t just top it up and forget it.
- A healthy boiler ums along quietly. If you hear banging, whistling, or a kettle-like rumble, something may be off. Like limescale or poor water flow.
- Damp patches, drips under the boiler, or stains near pipework need attention. And if radiators are cold at the top, they may need bleeding.
- Check the display for fault codes, and if your older boiler has a visible pilot light, note any change in colour or behaviour.
- Keep the area around the boiler clear as well. Good airflow helps, and clutter makes leaks or warning signs harder to spot.
Reasons to have an annual boiler check
A Gas Safe registered engineer will usually inspect key parts, clean where needed, test the flue, and check that the boiler burns fuel properly and vents safely. He or she can also check for tired seals, blocked condensate pipes or parts that are stopping hot water running. So avoids larger repairs.
Many boiler warranties need an annual service to stay valid. Not every fault means the boiler is finished. Some issues need a service. Some need a small repair. Others point to a boiler that is simply past its best.
Warning signs your boiler is struggling
- No heat or no hot water needs prompt attention, especially in winter. Rising energy bills, rooms heating unevenly, or a boiler that needs frequent resets can all point to a problem.
- Low pressure that keeps returning is another clue. So are leaks, kettling noises, and radiators that take ages to warm through. Strange smells matter too. Most boiler faults don’t produce a smell.
- If you can see a flame on an older unit, a yellow flame instead of blue can signal poor combustion. Also, look out for soot marks around the boiler casing.
- If you suspect carbon monoxide, turn the boiler off, open windows, leave the area, and get urgent professional help.
How to buy the right new boiler
Many boilers last around 10 to 15 years. But a well-serviced boiler may last longer. If faults are appearing, parts are hard to find or repair bills are stacking up, it may cost more to run, than buy a new one.
If buying a new boiler:
- Combi boilers are best for smaller homes, one bathroom or low hot water demand (it has no hot water cylinder, is compact and heats water on demand).
- System boilers are for higher hot water use and two or more bathrooms. They need cylinders, to cope with more demand.
- Regular boilers are older systems with loft tanks in larger homes, and suit homes already set up for this layout
Get at least three quotes, and make sure each installer is Gas Safe registered. Ask for the full installed cost, including labour, controls, magnetic filters, system flushing, and disposal of the old unit. Also ask what sort of thermostat is included.
Warranty length matters, but so does what keeps it valid. Check the service terms, the parts covered, and who handles aftercare if something goes wrong. A longer warranty is helpful, though only if the installer has done the job properly and registered it.
Visit iHeat, to take the quick questionnaire on how to choose a new boiler (you’ll need to know the boiler you have and flue location – the site shows how and where to look). This company also offers fixed-price air-conditioning.
A new boiler costs around £3000 (saving around £300 a year on bills). So start saving! The Energy Obligation Scheme. can tell if you’re eligible for free or discounted boilers.
The government’s boiler upgrade scheme can cover part of the cost of replacing fossil fuel heating systems with heat pump or biomass boilers.
You might qualify for grants if you:
- Receive certain benefits like pension credit or income support
- Live in a low-income household
- Have an older boiler that uses a lot of energy
It’s a good idea to check trusted sources like your local council’s website or official government pages for up-to-date information on who qualifies and how to apply.
Responsibilities for landlords and tenants
Landlords carry most of the legal responsibility for the safety and maintenance of boilers in rented homes. The law says they must:
- Carry out annual gas safety checks. Every year, a Gas Safe registered engineer must inspect the boiler and all gas appliances to make sure they are safe. And provide tenants with a copy of safety certificate within 28 days of the check.
- Keep boilers in good working order. Repairs and maintenance must be carried out promptly whenever there is a problem. For comfort, and to prevent gas leaks or carbon monoxide.
- Install and maintain carbon monoxide alarms. Landlords must put alarms where gas appliances are, including near the boiler. These alarms must be checked regularly and replaced as needed.
- Provide adequate heating and hot water. The boiler should be capable of supplying enough heat and hot water according to the tenancy agreement.
- Respect tenant access for maintenance. Landlords need to arrange repairs or servicing at reasonable times and must give proper notice before visiting.
Tenants also have a role in keeping the boiler safe and working. They must use the boiler correctly, report issues and allow access for checks and repairs. And regularly test carbon monoxide alarms.
Simple maintenance you can do
While complex repairs are best left to professionals, there are easy tasks you can do around your boiler to keep it running well:
- Bleed radiators: Removing trapped air improves heating and can stop cold spots. Use a radiator key to open the valve slightly until steam (not spray) appears, then close it. The instructions include an idiot-proof video! if radiator bottoms are cold, ask your boiler service engineer to remove the sludge.
- Check for Leaks: Look around the boiler and pipes for water or dampness.
- Keep the Area Clear: Ensure the space around your boiler is free of clutter and dust.
- Monitor Pressure: Boiler pressure should usually be between 1 and 2 bar. If it falls too low, top it up using the filling loop following the manufacturer’s instructions.
Installing carbon monoxide alarms
Carbon monoxide (CO) is a colourless, odourless gas that can leak from faulty boilers and is very dangerous. Installing a carbon monoxide alarm near your boiler is a must-have safety step. These alarms sound early warnings to protect your family from poisoning.
Watch out for symptoms like headaches, dizziness, nausea, breathlessness, and confusion. If anyone in your home has unexplained symptoms, or if the alarm sounds, switch off the boiler, open windows, and leave the property immediately. Call the emergency services from outside and never ignore signs something is wrong.
Signs of carbon monoxide leaks are floppy yellow/orange flames on hobs/ovens, sooty stains around appliances, pilot lights that go out and condensation inside windows.
Gas leaks smell like rotten eggs. Get everyone out and call Gas Safe Emergency Helpline (never smoke or use ignition switches). Locate your emergency control valve, to know how to switch it off.
