• Nicholas Hall

Why would the boiler stop working?


There could be many different reasons as to why your boiler or heating system isn’t working correctly. Your condense pipe could be frozen, a leak on the heating system which could lead to low pressure or a faulty controller.


There are two simple checks that you could carry out yourself, I have been called out in the past to rectify these issues which are easily overlooked. The first is make sure the switch is turned on to the boiler, I know, it sounds silly, but sometimes it is something as simple as this. The second is ensure the gas valve is fully open. If the gas meter is under the stairs which is also sometimes used for storage, the gas valve could be easily knocked which then delivers an insufficient amount of gas to the boiler. Simple checks but if you do not feel confident to touch anything, please always call a Gas Safe Engineer.


Not all boiler issues are as straight forward. This is why I want to give you 5 of the most common boiler issues that you could face so you know what to look out for.


1. Frozen condense pipe.

I have put frozen/blocked condense pipe at the top of this list as it is the time of year when this most occurs. This is a pipe that discharges water from the boiler into a waste either internally or externally to the property.

When discharging externally is when this pipe is more prone to freezing as it is exposed to the harsh winter weather that we can experience. This issue can be easily resolved by pouring warm water onto the pipe to help remove the blockage or by putting a warm towel on the pipe.


2. Loosing pressure.

You will not find this issue with all types of heating systems but if you have a combination boiler or a pressurised conventional heating system then this is something to look out for.

A boiler that shows low pressure, this can be anything below 1 bar, points to either a leak with the boiler or the heating system. Sometimes leaks are easily detectable, water dripping from the boiler or stains around radiators, valves or pipework.

The most common low-pressure issue that I have come across is when the safety valve is activated because the boiler has over pressurised, this is when the water is forced to exit the boiler which leads to a pipe that terminates outside. This normally happens because the expansion vessel from within the boiler has failed. It will need either repressurising or replacing.


3. Strange noises

All boilers make some form of noise when in operation, weather it is the fan or pump spinning, the burner igniting or valves moving and clicking. It can be worrying when the boiler then starts to make thumping or rattling noises and if you feel as though it could be dangerous it may be best to shut it off until a Gas Safe Engineer can attend.

Sometimes with a banging noise the boiler may be getting up to temperature to quickly. This can be do to with scale or a blockage in the system. There may be sludge within the radiators that can affect the boiler. A good way to identify this is cold spots at the bottom centres of the radiators when the heating is on. If this is the case a Powerflush would be recommended as the sludge will need to be removed for the system to work efficiently.


4. Valves/Controls

The valves and controls are not always found within the boiler. If the heating is coming on at irregular times or not at all it could be to do with the thermostat or the programmer. Sometimes either device could just need new batteries if they are wireless units, or they could have faults with them that cannot be repaired so a new unit will be needed.

With a conventional system you will have a hot water storage cylinder possibly in an airing cupboard. Connected to the cylinder by pipework will be zone valves. These control the direction of flow to either the hot water or heating. If these are clogged up with sludge from the system the valve may not be able to open enough to tell the boiler to ignite. An issue with hot water or heating isn’t always down the boiler depending on what system you have.


5. Error codes/Fault codes

Most modern boilers when they encounter a fault, will show the fault code in the display or flash lights at certain speeds to tell you why the boiler has locked out. Each code is different for different manufactures but a quick search on google, or if you still have the manufactures instructions, will tell you what the fault code means. It is not advisable for the homeowner to correct most faults. Although if the boiler has low pressure this is something that can be done without the need of an engineer. An engineer will only need to be called if the boiler keeps losing pressure


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