BoilerFaultCodesWhat the manual says
Manufacturer manualRefrigerant Thermistor Error
From this model's manual
Verified against the Ideal Hp290 installation & service manual.
What causes this fault?
This fault occurs when the system's control board loses communication with the sensor that monitors the temperature of the refrigerant liquid. The most common reason is that the sensor itself has developed an electrical fault or the wiring connecting it to the main controller has become loose or damaged. Because the unit cannot safely monitor these internal temperatures, it shuts down to prevent damage to the compressor.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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