Where is the orifice tube located?

**Leeroyws6** · 06-12-2010, 05:06 PM

hello.ive been searching threads to see if i could find where the darn orifice tube is located,but i cant.ive charged my system up after sealing a leaky line,and now im getting come crazy pressures.im pretty sure my compressor is shot.so im getting a new compressor,dryer and orifice tube,but im not sure where it is in the system.could someone chime in please?

**DaddySS** · 06-12-2010, 05:29 PM

Based on the description below it located in the hose that connects the drier to the evaprator core.

The plastic expansion (orifice) tube (2) is made of a mesh-screen (1) and orifice (3). The expansion (orifice) tube is located in the evaporator inlet pipe at the orifice connection. The tube restricts the high pressure liquid refrigerant in the liquid line. This restriction meters the refrigerant flow to the evaporator as a low pressure liquid. The expansion tube and orifice have filter screens which protect from contamination on both the inlet and outlet sides of the tube. When the engine is OFF the refrigerant in the system flows from the high pressure side of the system to the low pressure side until the pressure is equalized. This may be detected as a hissing sound for 30-60 seconds and is a normal condition.

**Cutlass** · 06-12-2010, 05:30 PM

It should be in the smaller diameter line between the condenser and evaporator.

**Cutlass** · 06-12-2010, 05:32 PM

ok here, I found this picture online.

**Leeroyws6** · 06-13-2010, 03:15 AM

oh.ok.i know exactly where it is now.thanks for the no brainer illustration.sure makes it easier with pictures

now im gonna install my new accumulator,tube and compressor and see what she does.btw...my freon sticker is gone.how much refrigerant should i charge it with?

**NastySS** · 07-02-2018, 07:43 AM

OK,,I know it's been a while, but I have question please. I have my new AC Delco Oriface Tube, but it came with no O-ring or Gasket. So, when you undo the connection to replace the OT, do you have to replace what ever medium seals that connection?

***SMWS6TA*** · 07-02-2018, 07:59 AM

yes otherwise it doesn't seal. IIRC the tube comes with a new o ring.

If in a jam you could reuse the old one but I would try to see if you can get new o ring.

**NastySS** · 07-02-2018, 08:09 AM

Thanks. There is an O-ring on the body of the OT, but that is not what you are referring to right? Any idea why it would not come with the O-ring like the Accumulator/Dryer did?

***SMWS6TA*** · 07-02-2018, 08:26 AM

IIRC when I did mine (a few yrs ago) it had an o ring, no gasket.

That O ring that you refer to was what I'm talking about. There should be one at each connection.

**NastySS** · 07-02-2018, 09:15 AM

Thanks again Scott. Just to clarify, that tiny O-ring on the shaft of the Oriface Tube is enough to seal the entire connection that you unscrew to access the Oriface Tube?

***SMWS6TA*** · 07-02-2018, 10:30 AM

Yes, believe it or not.

**NastySS** · 07-02-2018, 10:46 AM

I just got back from the Chevy Dealer. They said I would need the Evaporator case Seal, Delco part # 15-31054. They said it seals the connection you undo to access the Oriface Tube, which is the entrance aluminum tube to the Evaporator.. Steel and Rubber o-ring is 5/8 inch diameter for $11.42 + tax. I guess will see what is what when I get it apart.