Condenser above the Evaporator

[smoke]

I have checked all my books and I have never had this application before but I'm tasked with installing a condenser above the evap. It's a ductless split pack and the mech room just happens to be directly above the office space.

Please tell me if I'm wrong but I think as long as I pipe my refrigerant lines vertically upward for about a foot before running down through the floor that will keep the compressor oil from settling down in the evap correct?

Thanks all,
-smoke-

[hot wired]

will the unit be run all year.

[gordondemarko]

don't forget the p trap

[Toolpusher]

How much lift will be in the line set ?

You may very well need a trap, And should contact who the mfg is as to what they want.

I like to see traps when the condenser is above the indoor coil more then 20'

And watch how and where the trap is installed. I've seen an inverted trap at the outdoor coil, which was on a 30' lift. WRONG.

The indoor coil was flooded with oil and wasted the comp.

[gordondemarko]

when the condenser is more than 25 plus above the evaporator you put the p trap right next to the condenser to trap the oil from entering the compressor.the p trap separate the oil from the refrigerant. if i'm wrong that ok .still learning.

[smoke]

The condenser is only 3 feet above the evap.

So I should put a p-trap on the gas line (high side) right out of the compressor?
I've never seen a p-trap in the refrigerant lines. Definitely in the condensate line but not the refrigerant lines.

Won't the p-trap just trap some oil in the trap and therefor there will be a lower level of oil in the compressor?

What I'm concerned about is the oil migrating to the evaporator and smokin' the compressor.

I figured as long as I run the refer lines vertically out of the condensor like 1 foot up an then along the wall and down through the floor to the evap that would keep the oil in the condensor.

Keep the input coming guys I appreciate it.

-smoke-

[Toolpusher]

You don't need the trap in the hot gas line.

The purpose of the tap in the suction line is so the trap will have oil in it, and when the suction gas gets pulled back to the compressor, the gas goes through the oil and picks it up.
Taking it back to the compressor.
If the trap weren't there it would all be in the evaporator. And not make it to the comp.

[a/c-harris]

the p-trap needs to be on the suction outlet of the evaportator. that way the oil fills the trap and it will force it back up into the compressor. although since its only three feet you probably dont need it. call the mfg.

[doc havoc]

Toolpusher hit it on the head. You don't need a trap. And the reason for the trap is to capture oil and let vapor carry it back to compressor. Think of all the homes with furnaces in the basement and A/c at ground level. Very rarely will you see a trap.

[harv]

Toolpusher gets my vote on this one. The trap makes the oil return to the comp. In certain cases if a trap were not used all the oil would stay in areas were there is not enough refrig. velocity to carry it back to the comp. Proper pipe sizing and the use of traps helps to solves this problem.

[gordondemarko]

didn't know it was just 3 feet above the evaporator. sorry