A/C issues.

[Redneck Ram 2500]

Complete A/C rebuild, new condenser, compressor,dryer, evaporator, all new hoses. Added 3 oz of oil to compressor 1oz to condenser 1 oz to evaporator, and 2 oz to dryer. 7 oz is factory recommendations. Vacuumed 1.5 hours and charged with 2.5 cans of Freon. 1lb 14oz, also factory recommendations for 5.9 diesel. Start up pressures were 45 on low side 400 on high side on 85 degree day. Places a fan in front of condenser to bring down high side. High side stabilized at 250. Took a cruise down the road to check cruising pressures. 0 on low side and 150 on high side. Blowing cold air out the vent while cruising. So my intital thought was electric clutch fan ( not electric fan ) was bad. But why is my cruising pressure nearly pulling a vacuum. Did I get a bad orfice. Maybe wrong orfice? Orfice is in the liquid line and not visible by removing.

 

[crash68]

Not sure why you would have put the oil in anywhere but the compressor. The oil is extremely hydroscopic.
I wonder if there is a moisture issue causing your apparent restriction or it is some sort of foreign material plugging up the restrictor.
I'm guessing your going to have to pull the restrictor and see what's in there. Check to make sure that's were it's starting to get cold, the blockage might be further up.

 

[Bigseff23]

You should have an expansion valve. You might need to check your gauge. No way are you at 0, your low side cut off switch would cut power to the clutch because it would think you have no freon.

 

[Tach_tech]

Not sure why you would have put the oil in anywhere but the compressor. The oil is extremely hydroscopic.
I wonder if there is a moisture issue causing your apparent restriction or it is some sort of foreign material plugging up the restrictor.
I'm guessing your going to have to pull the restrictor and see what's in there. Check to make sure that's were it's starting to get cold, the blockage might be further up.

The oil gets circulated throughout the entire system, not just the compressor. The oil usually will also have a dye in it. That’s what is used to visually identify a leak, the dye in the oil.

What he did was the correct way for an entire rebuild, you add oil to each of the large components, evaporator,condenser etc. If you added all of the oil to just the compressor, it probably wouldn’t hold all of it and may hydro lock on the first time it’s engaged.

 

[crash68]

The oil gets circulated throughout the entire system, not just the compressor. The oil usually will also have a dye in it. That’s what is used to visually identify a leak, the dye in the oil.

What he did was the correct way for an entire rebuild, you add oil to each of the large components, evaporator,condenser etc. If you added all of the oil to just the compressor, it probably wouldn’t hold all of it and may hydro lock on the first time it’s engaged.

I'm well aware of how oil circulates through a refrigeration system, also how how it can become moisture laden and cause restriction issues. There is oils available for use with 134a in cars that are less/non hydroscopic.

Unless there is a suction accumulator on the system, add liquid anything to the evaporator and back to the compressor can result in a hydro-lock of the compressor. If a compressor has an oil capacity rating, it will hold that and then some. I'll have to find out, but I'm guessing that cars rolling off the assembly line only have refrigerant oil in the compressor, before the system is charged.
The oil is designed to drain out of the path of the refrigerant in the compressor, it's only the fact that the vapor refrigerant itself breaks down the oil that it moves. It's when liquid gets to the compressor massive oil lift happens.