It is a reciprocating compressor and it does have an oil separatoron it plus a slop pot on the suction side of the compressor.
I am not looking for a low head pressure, rather one thatwill give me the most heat without straining the compressor, or causing otherproblems.

At the moment I am considering around about 300 PSIdischarge pressure when it is on reverse cycle.
That does come out about the 75 f above suction that youmention.

You may find some variations in what I type as here we usethe metric system and I need to convert them to imperial for these posts.