What the manual says
Manufacturer manualCurrent temperature for warm stat sensor
What causes this fault?
This isn't actually a fault, but a live data reading showing the temperature of the internal sensor that manages your pre-heated hot water. It appears when the boiler is actively monitoring the heat of the water held inside the heat exchanger to ensure you get hot water quickly when you turn on a tap. If you see this, it simply means the 'Warmstart' function is active and the system is checking the current heat level.
DIY fix possible
No action required; this is an information code rather than a fault.Wait for the pre-heat cycle to finish and the display to return to normal.If you wish to stop this occurring, find the 'Comfort' mode setting and turn it off.
Avoid the next call-out bill
A cover plan would handle faults like D.4: no call-out fees, no surprise bills.
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Related fault codes
All 135 fault codes on the ecoTEC pro 24
Seeing a different code? Every code this model can display, in one place.