on line plumbing and heating 020 8875 5660

Tips Heating Problems – What to look out for

On combination boiler
instant hot water with no hot water tank

  • Check room stat is not turned down and also check the timer is turned on.

  • The pilot light may have gone out, check and to re light, depress the black or grey button for 30 seconds and release if applicable.

  • Then you should check the pressure gauge on the boiler. The pressure should be between 1-2 bar. If it is below 0.5 bar, the boiler will lock out for safety. You will have to refill the heating system to 1.5 bar by using the filling loop, which is generally under the boiler, maybe in a cupboard underneath or beside the boiler. The filling loop will be a flexible hose with either two taps at each end or a lever. Once the correct pressure is reached, you must turn it off fully.

  • If you have air in the top of a radiator, you can vent it but you must the re pressurise the boiler to 1.5 bar as explained above

  • The boiler may need re setting, reset button different on each boiler, refer to manual

On standard system
fully pumped with cylinder and tanks

  • Check pilot light, depress grey/black button for 30 seconds and release if applicable.

  • If only hot water or only heating does not work, it is more than likely a jammed zone valve. You can temporarily override the zone valve to stay permanently on. Zone valves are generally found in the cylinder cupboard, near the boiler or the boiler pump, they can be silver boxes, marked Honeywell. A lever on the end of the silver box can be lightly moved and lifted into lock position. DO NOT remove the boiler cover other than the small easy to open hatch as you will not be able to fix anything inside the boiler and you may cause matters worst.

  • Follow instructions for re pressuring system (3) if you have vented a radiator and the system is pressurised.

  • If no hot water, turn on immersion on hot water cylinder temporarily.

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On-Line Plumbing and Heating is a limited company and has been trading for over 20 years.
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