What happens when refrigerant oil is mixed in air conditioning systems?
If a mineral oil was to be used with R407 or R410A the oil starts to solidify and stick to the side of the pipes and orifices as the refrigerant breaks it down. This can be a problem in long pipe runs where oil can get trapped in the undulations of the pipe work installation. If installing a new R410A air conditioning unit and the existing air conditioning pipe work was used by a R407 air conditioning system then the pipe work theoretically can be used. The oil is the same synthetic variant and if the installer was to blast the pipe through with nitrogen to clear any residue of oil out of the run then there would be no problem.
Saving to be made when reusing air conditioning pipe work
When air conditioning companies are quoting there maybe significant savings in not changing the pipe work especially on long pipe runs. There is a environmental issue in replacing pipe work and if it isn't unnecessary then why do so. If the pipe sizes are the same or larger by one size i.e if the new air conditioning units are 1/4 + 1/2 gauge pipe and the old system is 1/4 + 5/8 gauges then there will not be a problem but more refrigerant may need to be added. Any larger may not be advised. For complete peace of mind use Mitsubishi Electric Air Conditioning.
Existing Pipe Work On Air Conditioning Units:
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