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A/C Thermostat and Expansion Valve Question. Almost back Together ! 200

Hi again,

I thought you would be riding cool by now but maybe I'm getting you confused with another poster. He was waiting to get his charged at nighttime? A Reason of humidity was given that doesn't make much sense. I see some strange things stated on here.
I like using my vacuum pump when the system is the warmest, period. It helps boil off everything in there.

The expansion device may have one or two lines. One line attaches onto a fitting that in the tailpipe of the evaporator. It is a pressure equalizer line for sensing pressure drop across the face of the coil cause by friction of the tubing. This line works in conjunction with power head through the body of the valve.

The power head, the disc on top, has its own line that works is its own separated chamber containing a diaphragm.
The line will have a bigger end that is fill with refrigerant to sense the boiling refrigerant going back to the compressor.
You must mount the bulb on the side of the returning line, no higher than the two O' clock position and no lower that four O' clock.
You want the end or tip pointing downward on any vertical lines and in this position you can mount it anywhere around it.
The rest of tubing coiled and held higher than the bulb. This way any liquid in the bulb we want to stay in the bottom end.
This is so gas will be the only thing operating against the power heads diaphragm and all the liquid boils upward will be used to operate the power head.
Do not a bulb on the bottom side, ever, as oil in the system travels down the tube on the bottom along with liquid refrigerant.
We want to sense both liquid and vapor droplets.
Any oil that will act as an insulator of true temperature.

A person can move the location of that bulb or insulate that bulb with a thin piece of plastic and move the liquid and saturated vapor droplets more or less along the inside the evaporator coils length. We then adjust adjust the rest of the return line into a superheat range. Usually several inches past the bulb and down the tailpipe. This can effect efficiency of the cooling system and it's safe operation.

In all cases you want that bulb fastened tightly. The spring clip should surround the bulb to transfer as must coldness from the line to the bulb.
You want to coat or insulate that whole area from any outside air influence. Air has moisture and moisture is where the most of the heat resides.
We need to know what the coil fins got and that we only send back super heated gas vapor to the compressor.

The thinner line from the thermostat works the with same principle but it is push into the coil fins so it can sense incoming air flow and whether the coil has iced.
The exact place I do not know but it has to be inside that enclosure and if you can spot a hole in the side of the fins, put it in there. Most likely approximately one fourth from the top to midways will be fine.
We always want that coil as cold as possible so it wrings water out of the air but not freeze up. Not running at thermostat on its very maximum setting will not lock out the modulating function of a thermostat.
Cranking it all the way will and then you will lose air flow passing ability from frost buildup. It's not meant to be a snow cone or ice cube maker.

Electrically or for as the two wires, that's all it needs. It is only an on and off switch to a time delay relay or straight to the compressors clutch. Follow one of them to either place. The other is power that you can test for with the key on.

Looking forward to a nice follow up report. I bet it will be worth reading!

Phil








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