Toshiba r407C VRF Issue

Hi All ;)
Going back too a site on tuesday too look at one of these old toshiba vrfs the customer is saying for the past few weeks its been tripping the breaker every few hours or so after everytime he does a power reset. ive allready been too site for a short visit and checked both the fixed speed and inverter compressors they were both ok and the outdoor fan motors are ok as the unit does run for a while. toshiba recommended recovering the gas charge as the compressor could be overheating and tripping the main breaker? just wondering if anyone else has had a similar issue with these units or any ideas what too look for next? any help appreciated ;)

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407c is a complicated refrigerant because it is a blend.
If it has every had a leak and been topped up rather than having the whole charge replaced or if it is slightly short of refrigerant now then the blend can sometimes turn into a refrigerant that resembles R410A.

In both situations the result is higher discharge pressures and possibly higher running amp's.

Pulling the charge and compare the weights against the displayed weight on the unit, if it is out consider a replacement but the customer must be informed because it won't be a cheap option and no guarantee.

Rob

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