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How To Avoid Common Boiler Faults

How To Avoid The Most Common Boiler Faults ?

A boiler breaking down is a home’s worst nightmare and will leave many households hostage to the cold for days until it gets repaired. Even though modern boilers have become increasingly more reliable every boiler will break down once or twice within its lifetime. The most expensive boilers on the market can even break down and therefore it is wise to make sure you are aware of how long the manufacturer guarantees the warranty period for. It is also sensible to make sure that any heating engineers working on your boiler are knowledgeable about that boiler and are of good understanding. 

If your boiler is outside of the manufacturer warranty period, each call out will cost you between £150 and £250 depending on what part of the boiler has broken down. This is why it is vitally important to make sure you research the majority of boilers on the market and understand which manufacturers give you the best in terms of warranties. Installing a brand new A rated boiler can save you a lot of money on your gas bills but choosing the right boiler is the key as an unreliable boiler can end up costing you unexpected expenses in the long run.

A good source of information to ensure that the boiler you are getting is a reliable boiler is the annual boiler reports by Which; they test consumer goods and publish unbiased reviews on what they find through their research and testing. Worcester Bosch, Valliant and Viessmann always tend to appear within the very top of their boiler review. The warranty period for these boilers are different depending on who your installer is and the warranty terms so make sure that any warranty you receive includes all parts. 

Keeping your boiler maintained over the lifetime of its use is very important in keeping your costs down. Most of the faults associated with a boiler surprisingly do not include a heat exchanger (the part that most people have heard of). It has been reported that it is actually the circuit board that fails more often than most and it is also the most costly repair job, costing an average of £280 to repair and put right. Below we have a list of the cost of maintenance work on your boiler. 


  1. Circuit board – £270 – £280
  2. Combustion fan – £230 – £250
  3. Diverter valves – £180 – £200
  4. Ignition system – £100 – £120
  5. Gas valve – £210 – £230
  6. Pressure relief valve – £100 – £110
  7. Automatic air vent – £90 – £100
  8. Water pump – £200 – £220
  9. Thermostat – £100 – £110
  10. Thermocouple – £80 – £90

We have come across some boilers that have been so badly maintained that they need to have a number of these repairs carried out at the same time which ends up making the repair bill skyrocket to insane proportions. The best advice we can give to you on boiler maintenance is to make sure the boiler does not overheat by working harder than it needs to. Making sure your boiler water temperature is set no higher than 65c can ensure that all the parts of your boiler are not being overworked. Anything higher than 65c is unnecessary and can cause parts to wear out much quicker. 

It is also important to check that the radiators are working properly and to their maximum capacity. Venting the air out regularly is also a good way of keeping up the maintenance of your boiler. You can tell if there is air or sludge present in your boiler if the top/middle part is cooler than the edges. If the air has been vented from the radiators and the middle is still cooler then it means there is sludge in the radiator. In this situation your boiler will have to work harder than normal to keep the room temperature up. 

Using your thermostat effectively by setting it to an optimal temperature will mean that you don’t overheat your house, you will save money on fuel bills and you will also increase the work life of your boiler. Place your thermostat in the room that is the warmest as if you place the thermostat in a room that is cool your boiler will be working harder and your rooms will overheat.

If you follow the advice mentioned above then the most common boiler faults are going to be avoided for years to come and they will help you save money on your repair bills.  

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Previous Successful Applicants

I had boiler replaced two weeks ago , everything went smoothly as I have been expecting, engineers came on site spot on time everything boiler is working good , place left tidy , i am impressed with Company Warma , definitely would give 5 star

Barry Jones
Rating: 5

Don’t often do reviews but felt this warranted one. A little slow getting the fitting date sorted out but once this had been sorted everything was plain sailing from start to finish. Can’t fault the engineer who fitted my combi boiler. Nothing was to much trouble to him, explained everything has he went along. Would recommend without hesitation.

Malcom Brett
Rating: 5

The old boiler and tank were removed and the new condensing boiler fitted by the two installers from XL Heating. They were friendly, informative and tidy, working well as a team for two days.
So far very happy.

David Garrod
Rating: 5

From initial enquiry to completed installation of a new boiler (and associated works) took less than a month.
The whole process was stress-free and very straight forward and I’m very happy with the new boiler.
I’m grateful to Andrew Toyne & his colleagues for the excellent service they provided (All Warma staff were extremely helpful and professional) and would not hesitate in recommending Warma to others.

Mark C
Rating: 5

Absolutely made up with the installation, from the initial phone call through to the engineers installation. Every step of the way I was kept updated. Customer service is amazing and Dave the installer did a fantastic job. Thank you Warma I would highly recommend 10/10

Karen Kelly
Rating: 5

Happy with the work done.They were professional and friendly and explained everything they were doing

Rating: 5
Michael Cornish

Michael Cornish