D.8 Low
Your boiler is receiving a signal from your thermostat or external controls asking for heat, and it is operating as it should.
Technical description: External controls heat demand
Typical repair cost: £0 (including labour)
DIY fix possible
Check your room thermostat or timer settings to see if you are calling for heat.Lower the temperature on your thermostat to see if the code disappears.No action is required if your heating is currently turning on and off when you expect it to.
Protect yourself from future repair bills
A boiler cover plan would cover faults like D.8 — no call-out fees, no surprises.
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