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©G Hendra Nov 18
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Temperature Sensor Errors
E221, E231, E251, E320, E653, E901, E902, E903, E904, E906
Temperature sensor errors are a pretty easy fault to diagnose and usually results in
replacement of the sensor that the error code corresponds to. But, it’s still worth
checking to see if the sensor is at fault before changing it. All you’ll need is a
temperature probe and a multi-meter.
Using the K4 button on the outdoor unit, you can check what almost all the sensors in
the outdoor units are reading, if your probe’s reading is massively different to what the
unit is reading, you have a problem.
If the sensor that you’re looking for has a blank reading on the PCB, you also have a
problem.