All A/C is repairable but sometimes it may not be worthwhile.
This Fujitsu was something of a borderline case.
Had it been a stand alone unit it would probably have been scrapped but because it was part of a larger system it was repaired.
The Fujitsu Condenser Unit on the left is one of four identical units that serve a large open plan office. It was tripping the circuit breaker on its electrical supply and had stopped working.
Further investigation found the 3 phase compressor motor, inside the sealed black cylinder shown here, to be at fault. One of the motors windings was ‘down to earth’. In this situation the only feasible repair is to fit a new compressor unit. A sample of oil was extracted from the machine for testing.
The red colour in the right hand bottle indicates acidified oil and is consistent with the motor winding insulation having overheated and failed. A detergent cleaning solution was forced through the system using pressurised nitrogen gas to flush out any lingering acidic oil residues.
A New Compressor from Fujitsu was ordered. After taking delivery, arrangements were made to continue with the repair on a day with a forecast for reasonable weather.
Out with old, In with the new. The system was recommissioned and remains in use.
Post Mortem. Curiosity got the better of us so we cut open the compressor enclosure to have a look inside. On the Fujitsu rating plate it said ‘Kawasaki’ (Japan), on the compressor casing it said ‘Bristol’ (USA) whilst inside it said ‘Mexico’
Cylinder Head removed.
The Crank, with only a splash-fed oil supply to the upper big end, was shafted.
Thrown a rod.