Get a warranty from a good installer and it will not be your problem if
there is one. Most good HVAC people do not believe in reusing the lines,
whether or not they are purged.
Don Young

"Walter R." wrote in message
news
I am replacing my old air conditioner with a high efficiency model.

The old unit uses Freon (R-22), the new unit uses Puron (R-410A).

The compressor and evaporator coil will be new. No problem. What concerns
me, is the two pipes in the wall that run from the compressor to the
evaporator.

Since Freon and Puron seem to be incompatible with each other, is it
necessary to purge any remaining refrigerant/oil from the tubing? What is
the proscribed procedure?

Just trying to keep an eye on the contractor. I am the one who has to live
with the system.

Thank you.

--
Walter
www.rationality.net
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