BoilerFaultCodes.com
E 84 Medium

Your boiler is slowing down its performance because it has detected that the gas pressure coming into the unit is too low to run at full power.

Technical description: Capacity reduction for detected low gas inlet pressure – check the CO2 calibration values.
Typical repair cost: £80-200 (including labour)

DIY fix possible

Check that your gas emergency control valve (next to your meter) is fully openIf you have a pre-payment meter, check that you have sufficient creditCheck if other gas appliances, like a hob, are working correctly to rule out a grid supply issue

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