My truck is spending another nite.........

[Stresst]

Most of you know I have been having a ton of trouble with my 2000 Escalade a/c. Last week a new shop found that the condenser was plumbed backwards but it still would not blow cold. He wound up removing the orifice and reinstalling it in the condenser. The a/c was the best its been this summer but not quit rite in the front and worse in the rear. Figured once we install the new rear expansion valve the system would be more efficient and my nightmare would have been over.

But it seems my truck is spending another nite at the a/c shop. They installed a new rear expansion valve and removed the orifice from the condenser and installed it where it belongs. Guess what? NO EFFFEEIN GOOD! What else is new! But this time the front and rear didnt work. So they opened up the rear box and installed another rear expansion valve. Guess what no good either. So the owner comes over and tell me they want to install an orifice in the rear instead of the expansion valve. He said he did it numerous times "when the old chevy's had three valves and they had issues diagnosing which one is no good". So I tell him go ahead. He modified the rear evaporator tube to accept the orifice and after a little brazing it was installed. He puts everything back together and still no friggen good.

He decides to remove the grill (rather for me to remove it again) for him to install the orifice in the condenser again. He gets it back together and the front works half way decent but the rear sucks.

Can anyone tell me what is going on? Are they valves supposed to be wide open and close under pressure?

 

[SunlitComet]

The one for the front is a fixed hole. The one in the rear acts like a variable one but is sensitive to the evaporator temperature with the orifice opening to a certain point when evaporator get warm and vice-versa. Can the mech do a flow or pressure test of some sort to see if the line with y-block is not partially blocked between where the orifice goes and condenser. Being as how you had leak sealer in there I am wondering if it has accumulated in low heights levels of the piping and is slowing things down.

 

[Stresst]

The one for the front is a fixed hole. The one in the rear acts like a variable one but is sensitive to the evaporator temperature with the orifice opening to a certain point when evaporator get warm and vice-versa. Can the mech do a flow or pressure test of some sort to see if the line with y-block is not partially blocked between where the orifice goes and condenser. Being as how you had leak sealer in there I am wondering if it has accumulated in low heights levels of the piping and is slowing things down.

Probably not but I dont see why he cannot take it out.

Getting back to the rear expansion valve, if you blow in one side should it come out the other side??

 

[SunlitComet]

yes but if the temperature bulb is really cold it will be on the practically closed position.

You would need to put a fixed air pressure and a gauge on the inlet side and watch to see if the pressure drops or rises as you cool or heat the bulb to test functionality. It is till a small hole and may not be that easy to just blow in it.

 

[Stresst]

yes but if the temperature bulb is really cold it will be on the practically closed position.

You would need to put a fixed air pressure and a gauge on the inlet side and watch to see if the pressure drops or rises as you cool or heat the bulb to test functionality. It is till a small hole and may not be that easy to just blow in it.

I personally thought it was closed and when refridgerant hits it or pressure whatever you want to call it it would open. If you can blow air through it when its in your hand IMO there is no way 5 valves are no good. Something else is not rite.