Mitsubishi fault code 4108

[boulting]

Hi

I've just been to look at a Mitsubishi PURY-P500YEM and I'm getting Fault code 4108 but the green light is'nt flashing and the indoor unit is still running, I've checked on the mitsi site and it mentions overload on compressor, I checked the outdoor unit to find the inverter compressor is running but the other seems to be off. Due to the snow I didnt want to remove the electrics cover for obvious reasons and I'm going to return tomorrow can anyone tell me what I should be looking for.

Many thanks

[Thermatech]

This model has 1 inverter compressor & 1 direct on line compressor with contactor & overload.

The 4108 fault is overload activation on the direct on line compressor.

Suggest check 3ph power & operation of the contactor & overload.
Mega the compressor windings & check windings resistance.

If all check out ok run the compressor & see what start & run amps are.

[boulting]

Cheers for that Thermatech I'll try that tomorrow

[boulting]

Right, I found the overload and reset, checked windings all OK. When we come to run the system again it came up with fault 0403, Mitsi say its a communication error between main board and inverter board because we did have to pull wires off the boards to get to the overload to reset it. we have reconnected the plugs on the board a few times now and also buzzed out the interconnecting wires for continuity all seem ok. When we fire up the system it makes a few clicking noises and what sounds like a small fan running and also there is a high pitch whistle then after a couple of minutes the unit trips on 0403.
Any more help gents

[hyperion]

Check to ensure that the inverter addresses have not been accidently changed. Check that SW2-1 on the INV board is ON, also that SW2-1 on the FAN board is ON.