Boiler repressurisation

When central heating isn’t working, a loss of water pressure can often be the cause. Most boilers have a water pressure indicator on the front and this should show between one and two bars of atmospheric pressure. If it shows less than one then your boiler pressure is too low and will need to be repressurised.

To repressurise your boiler, follow these 7 steps:

  1. Switch off the boiler and ensure the system is cool
  2. Locate the filling loop, this is usually grey flexible hose with small valves at each end and it is normally located underneath your boiler
  3. Check to make sure the hose is securely fastened to both valves
  4. Valves can usually be opened by turning tap handles, or by using a flat headed screwdriver
  5. Open both valves, this will allow cold mains water into the heating system - you should be able to hear water filling the system
  6. Watch the pressure gauge until it gets to 1.5bar. Once it has, close off both valves one by one
  7. Once the pressure is at the required level and the valves have been closed off, switch the boiler back on and reset it if required to do so.

Please note: New Boilers approx. up to  ( 3 years old ) will have an internal filling loop operated by a key, sited on the left hand side at the base of the boiler. 

If you cannot locate the filling loop, pressure gage or if the above does not appear to work then check the manufacturers guidance provided with the boiler.

If the problem persists, contact us as there could be a leak somewhere in the system.

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