Did he reuse the old line set? Did it have an inverted loop.
The inverted trap requirement has been around for a long long time. Does your line set rise higher then your coil at any point. Does the line set have any incline before it goes outside.
Had a local inspector tell me I would have issues with oil return because of inverted trap. Showed him the installation manual. He did not have much else to say about it.
You went cheap & bought the equipment to save a few bucks (and have no warranty BTW). I'm betting the only thing the "installer" did was connect lineset & charge.
Have him explain it to you & correct it if need be.
You won't get much help here for internet purchased equipment.
I have had lots of internet discussions, but I've never met any ruder people than some on this thread. I've rather come to expect this from HVAC people though. They seem to think selling and installing new equipment is their God given right. Well, I'm here to tell you it's not. I now have two of these systems installed and I'm sure they will they will last a very long time. The installed cost is less than half of what it would have cost if I'd have hired it all out, so it's not a minor deal to someone who doesn't have a lot of money. So you who think you are entitled somehow to do what I can do for myself and charge me for the privilege, drop dead for all I care.
For those that had a helpful word or two thanks and best of luck to you. I'll not be back here ever.
Allows liquid to boil off.