Is your AC not cooling correctly? Technical bulletin:

[OrangeCrush]

My H2 is an '03. I hadn't noticed it last summer since I bought it late in the summer and I guess I didn't need the AC that much.

That was until the last couple of weeks where the temps are getting close to 100. I noticed (as it seems with most GM's) that the AC doesn't cool as much when I come to a stop.

Typically if the AC condenser doesn't have enough air flow (eg. being at a complete stop), you can help cool the condenser by adding a supplemental electric fan over it.

However, before I jumped on that, I recharged the AC at my shop... it didn't help much so I took it to a tech friend of mine and he checked it out.

Turns out that certain Yukons and H2's have a service bulletin that pertains to the orifice tube being put in backwards from the factory.

He evacuated the system, turned the orifice tube 180 degrees (normally they're suppose to go in one way only... the arrow should point towards the front of the truck) and the AC works perfectly.

Anyway, just thought I'd mention it if any of ya'll don't seem to have your AC working correctly when sitting still at a light.


HTH's,

Mark

[KenP]

Thanks Mark. There's been talk of A/C problems during past summers so I know this info will help some.

[SnakeH2]

Originally Posted by PhilD

Never had a problem with the a/c (touch wood)....

He said touch wood

[devilsfan]

Mine has been cooling fine, but never on the right setting. If I put the button on (the one with the snowflake), all I get is hot air. If I leave it off, it cools down great. Never been worth the hassle to take it to the dealer (and wait a week while the wrong part is ordered, returned, then finally fixed).

Stacy

[ree]

Originally Posted by devilsfan

Mine has been cooling fine, but never on the right setting. If I put the button on (the one with the snowflake), all I get is hot air. If I leave it off, it cools down great. Never been worth the hassle to take it to the dealer (and wait a week while the wrong part is ordered, returned, then finally fixed).

Stacy

Um, it's a snowflake with a slash through it, meaning turn off AC when you select it.

[Boss Hoss]

Its been really hot here lately and ive been wondering if something is wrong. On one hand i think that its just a big truck and takes a while but on the other hand im thinking it should be able to cool off much faster. Ill probably bring it to a local mechanic since the closest stealership is 2hrs away.

[H2 Bill]

Originally Posted by ree

Um, it's a snowflake with a slash through it, meaning turn off AC when you select it.

x2

[devilsfan]

Originally Posted by ree

Um, it's a snowflake with a slash through it, meaning turn off AC when you select it.

Um, no it's not. It's a snowflake. There is no slash. I just checked. I have a late 03 model. Did they change it later on?

Stacy

[MarineHawk]

Originally Posted by OrangeCrush

... the orifice tube being put in backwards ... turned the orifice tube 180 degrees (normally they're suppose to go in one way only ... the arrow should point towards the front...)

What would Freud say about all that?

[HummBebe]

Originally Posted by MarineHawk

What would Freud say about all that?

That you really wanted to marry your Mother

[ree]

Mark, Same thing here. We had a run of 90's a couple weeks ago and the AC just couldn't keep up. Turns out the orifice tube on mine was in backward too. Dealer fixed it while it was in on other issues and now it works great.

[ree]

Full bulletin:

Document ID# 1360249
2003 HUMMER H2 Insufficient HVAC System Cooling, Hissing Noise on Engine Shut Off (Inspect/Reposition Orifice Tube) #03-01-39-010 - (Jul 24, 2003)

Important: The Information contained on this DVD is dated October 7, 2005. Please visit your approved GM internet portal for the latest published Service Bulletins, Campaigns and Preliminary Information.

Insufficient HVAC System Cooling, Hissing Noise on Engine Shut Off (Inspect/Reposition Orifice Tube) 2003 HUMMER H2
Condition

Some customers may comment on insufficient cooling of the air conditioning system. Also, a loud hissing noise may be heard when shutting off the engine.
Cause

This condition may be caused by an incorrectly installed orifice tube. It may be installed backwards.
Correction

If the vehicle exhibits insufficient cooling and a loud hissing sound is heard upon shutting off the engine, inspect for a mis-installed orifice tube. Correct the installation of the orifice tube if it is backwards. Refer to Expansion (Orifice) Tube Replacement (SI Document ID #703189).
Warranty Information

For vehicles repaired under warranty, use:
Labor Operation
Description
Labor Time
D3200
Tube, Expansion (Orifice) - Replace
Use Published Labor Operation Time

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

? Copyright General Motors Corporation. All Rights Reserved.

[ree]

BTW, mine hissed, slowly and for a while after shutoff before (2 minutes). Now it still hisses, but for a much shorter duration (~20 seconds).

[ree]

Originally Posted by PhilD

Mine used to work like that, but when I had it broken into they bust the a/c controls, so it was replaced. Now it shows a snowflake when the a/c on, and nothing when it is off.

Was this interface fixed/improved in later model years?

[OrangeCrush]

Originally Posted by ree

Was this interface fixed/improved in later model years?

Must be because mine works like Rees. When it's on, I get nothing. When it's off, I get a snowflake with a slash. ('03)

Mark

[GeorgeSSSS]

I have an '05. Snowflake when AC on; nothing when it's off.

[DDWH]

Originally Posted by OrangeCrush

Must be because mine works like Rees. When it's on, I get nothing. When it's off, I get a snowflake with a slash. ('03)

Mark

X3...mines the same way

[menuserve.com]

so if i have the hissing after shut off should i simply contact my local hummer dealer to have this checked out?

[OrangeCrush]

Originally Posted by menuserve.com

so if i have the hissing after shut off should i simply contact my local hummer dealer to have this checked out?

I think I would. I know that now that mine has been repaired, not only is the ac 100% better, there is no hissing afterwards...

Can't hurt to check it out.

Mark

[devilsfan]

Must be a GM thing. The Slade has the same as the later model H2s - snowflake shown when the AC is on.

Stacy