Can anyone help with this problem on Keith style R12 system.

1) Compressor great
2) Condenser great
3) no leaks
4) flushed all the lines
5) Cleaned expansion valves
6) Pressures great

After the expansion valve, the pipe to the evaporator is ice cold, there's no coldness on the pipe coming out of the evaporator and no cold air.

What on earth am I missing to make cold air?

Mike

Had the same problem and my evaporator was so dirty and clogged up like it wasnt cleaned in years. I cleaned it an now you can hang meat in the back.
Mark

I am doing that next! Thank you for the confirmation

Clogged evap.

Let us know if that works please. My AC could always be colder. I'll clean my evap up if so.

You mention expansion valve cleaned, that does not mean it’s working great. Given that they are often not too much $$$s. If you crack the system to flush it and clean the evaporator, put a new one on.

They are witchcraft to find new ones, they look they are out a tractor AC.

So I'm an AC contractor by trade... you say you have great pressures. What are they?
Cold refrigerant line leaving the expansion valve but then not cold when out of the evaporator IS NOT a sign of a dirty evap coil. You would have the opposite affect. If the evap is dirty and air can't move across it (no load on coil) the refrigerant will not pick up any heat and evaporate in the evaporator coil. The suction line leaving the evap coil going back to the compressor would be ice cold and most likely the evap would start to frost and freeze up.

The problem your having is usually a result of low refrigerant charge or some sort of restriction in the system. Either a bad expansion valve or a clogged filter drier. What is happening is your not flooding the evaporator with refrigerant and the refrigerant that is going into the evap from the expansion valve is evaporating before it probably makes it even a quarter of the way through the coil.

What are your pressures? It would also be helpful to measure the temperature of the liquid line (line leaving the condenser coil) with a temperature clamp type thermometer. This reading combined with the high side pressure in the system while that temperature reading is taken will allow us to calculate the subcooling value of the refrigerant in the high side of the system and be much easier to troubleshoot if your low on charge or restricted.

...because they probably were! That whole assembly looks like it was designed on the Monday after a Chief's Superbowl victory.

Is the part you are having trouble finding ES26101-3 or ES26101-5, by chance? Loyds/Bakersfield Jet has a -3 and -5 available as NOS. The real witchcraft will be getting them to part with it for less than the cost of a PVC for your molar!

I recently went several rounds with my Keith unit too and we eventually found that the problem was in the Fan Assembly. It’s virtually impossible to find parts or anyone who will support these things so we just took everything apart and gave it a good cleaning with contact cleaner and some light sandpaper around the brushes. Put everything back together and now it’s working like a champ!

Listen to the AC guy.

^^^^

He asked the right question….”what are your pressures”?

I’ve done some ac work myself and have been around a lot of ac technicians and it’s all about the pressures. Tech’s that are really good use those gauges like a doctor uses a blood pressure cuff and stethoscope.

Pressures are 160 and 30 If that’s useful information, I had them a little higher on the low side and some old guy told me to takeoff a little pressure . Any ideas?

Is a internally Clogged evaporator, symptomatically different than One that is externally, covered in dust?

Sounds a little low on the high pressure side unless it was an awfully cool day.