A central heating boiler system is a fantastic commodity of the modern world: where would we be without it? Thanks to its efficiency, we have hot water on tap, and a nice toasty house at the flip of a switch. No more collecting firewood for warmth (unless that’s your thing), or heating up buckets of water over the fire for a wash. No, thanks to the Romans, whose earlier engineering feats were the inspiration behind modern heating, we can live life in relative comfort and warmth. But no matter how excellent the modern central heating boiler system is, sometimes, it likes to break.
Here, we go through some of the most common reasons a boiler or central heating system might be struggling, and what you can do about it…
The Boiler Won’t Turn On
Or keeps turning off. You may simply need to reset your boiler by turning it off, leaving it for ten seconds, and turning it back on again. If this doesn’t work, check your
Pilot Light
If your pilot light keeps going out or won’t ignite at all, this could be down to certain variables, including:
- Mains gas supply: always check your mains gas supply by testing your other gas appliances such as your cooker. If these don’t work, the problem is with your gas supply, not the boiler, and you’ll need to contact your gas supplier to rectify the problem.
- Dirty pilot light tube: your pilot light may not be able to light due to a buildup of dirt and debris in the pilot light tube. You can remove this to clean it, but only do so if you’re confident in doing it correctly.
- Low water pressure: check the pressure on the pressure gauge; it should be between one and two bars of atmospheric pressure
Other problems that you could face with your central heating boiler system is the heating coming on, but perhaps being too hot. This could be a sign of a broken or faulty:
Thermostat
If the thermostat is faulty it won’t be able to ‘tell’ the boiler when to stop heating the water in the radiators, leading to an overheated room.
Other Problems
Radiators that are hot on the top and cold on the bottom are an indicator of rust and sludge in the radiators, and the system will require a flush through (or drain down). ‘Banging and clunking’ can also be a sign of this, although a noisy central heating system can also indicate trapped air.
Radiators that are cold on the top and hot on the bottom are a definite indication of air in the system, as the air traps the hot water and prevents it from travelling to the top. Try bleeding your radiators to see if this resolves the problem.
When It’s Time To Call The Experts In…
If you have tried to fix your central heating boiler system yourself to no avail, or if it’s a problem that requires expertise, then why not give ACR Plumbing a call? We have over twenty years experience in the industry and guarantee 100% customer satisfaction 100% of the time. We also have an emergency helpline for any of those pressing plumbing emergencies!

