How to test my boiler/heating system?

How to fully test you're heating system BEFORE the cold snap... and save money!

Heating companies get extremely busy during the autumn months, so you could end up waiting weeks for your system to be fixed, or be forced to use a more expensive company. Getting caught out in the middle of the winter doesn't just mean a cold house but also no hot water!
So to save time, money, hassle and cold toes, here's a basic check of functions.

Important, please read through fully first before, commencing.


How to test

When the system is cool...

1) Turn off your programmer/boiler and turn your room thermostat down to 0, if you have one, if not use the thermostat on your boiler.

2) Turn on your boiler/programmer and central heating, making sure your hot water is turned off.

3) Turn up your room thermostat or boiler thermostat, and make sure the boiler fires up.

4) Wait for 5-10 minutes, and feel the top and bottom of you radiators in each room, make sure they warm up evenly.

5) Turn down the room thermostat/boiler thermostat and make sure the boiler to turns off.


If you have a combination boiler (WITHOUT a hot water cylinder/copper tank usually in an airing cupboard)

6) Turn on the hot water wait for the water to warm up and check that you get a steady, even flow and that the temperature is stable.


If you have a conventional boiler (WITH a hot water cylinder/copper tank)


6) Check that the cylinder thermostat (stat) is set to 0, and turn on the hot water at the programmer

7) Check the boiler has NOT fired up, if it has you may need a new cylinder stat, this is important as you could risk scalding!

Turn up the cylinder stat to approximately 55oc (hotter risks scalding, lower risks legionella) and check that the boiler fires up.


All done, provided you followed these instructions and the boiler behaved as stated your systems basic functions seem to be working.

If your system hasn't behaved as stated please make sure your Plumbing and heating engineers are qualified to do the job. Follow this link to find out... What qualifications do I look for in a plumber?

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Note this is NOT a safety test, and only checks the basic functions of your heating system. If you feel you are not competent to complete this call a professional... 01252 405252.

Make sure your Plumbing and heating engineers are qualified to do the job. Follow this link to find out What qualifications do i look for in a plumber?

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