Evaporator temps around 70 degrees, vent temps only 45 degrees at best
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Re: Evaporator temps around 70 degrees, vent temps only 45 degrees at best
Hi! Did you, by any chance, ever come upon a solution? I am experiencing this exact same thing right now, with the exception of the extent of parts replaced. I have replaced my compressor, receiver/drier, both TXVs, and the manifold hose assembly that mounts to the compressor(that's where my leak was, as it turns out). Now , the system holds vacuum, has been charged, but as I said, I have the same symptoms you describe here. Any advice is appreciated.
Re: Evaporator temps around 70 degrees, vent temps only 45 degrees at best
Sorry, I have been out of town for a bit.
Those drive pressures say you are undercharged a little. I would expect to see over 200 psi @ 84f with a solid heat load.
Add an ounce, re-test, repeat. You can add small quantities of vapor on the low side while driving, then let the system stabilize while watching the gauges.
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Certainly we understand superheat & sub-cooling. Try "Sensible Heat Load" - after you stop laughing, you will understand why we largely ignore the terms while servicing MVAC. The heat load is anything but "sensible" after a car sits in the sun all day. With 140f evaporator inlet air, liquid refrigerant @ 125f (with a 5f subcool) A compressor output volume that varies from 10% of system capacity to 200% depending on driving speed, and a condenser airflow from 5% to ? depending on conditions & equipment.
For a building, you calculate the sensible heat load (100f outside, R14 insulation, 2400 square feet etc.) size the equipment, and run constant airflow speeds over each heat exchanger. You can plan a fixed subcool & superheat, then charge accordingly.
.
Those drive pressures say you are undercharged a little. I would expect to see over 200 psi @ 84f with a solid heat load.
Add an ounce, re-test, repeat. You can add small quantities of vapor on the low side while driving, then let the system stabilize while watching the gauges.
.
Certainly we understand superheat & sub-cooling. Try "Sensible Heat Load" - after you stop laughing, you will understand why we largely ignore the terms while servicing MVAC. The heat load is anything but "sensible" after a car sits in the sun all day. With 140f evaporator inlet air, liquid refrigerant @ 125f (with a 5f subcool) A compressor output volume that varies from 10% of system capacity to 200% depending on driving speed, and a condenser airflow from 5% to ? depending on conditions & equipment.
For a building, you calculate the sensible heat load (100f outside, R14 insulation, 2400 square feet etc.) size the equipment, and run constant airflow speeds over each heat exchanger. You can plan a fixed subcool & superheat, then charge accordingly.
.