View Full Version : Is your AC not cooling correctly? Technical bulletin:
OrangeCrush
06-15-2006, 01:32 AM
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
Thanks Mark. There's been talk of A/C problems during past summers so I know this info will help some.
MarineHawk
06-15-2006, 03:11 AM
... 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?:confused:
HummBebe
06-15-2006, 03:26 AM
What would Freud say about all that?:confused:
That you really wanted to marry your Mother:D
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.
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 (http://elcovaforums.com/forums/#ss1-1360249)
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 (http://elcovaforums.com/forums/#ss2-1360249)
This condition may be caused by an incorrectly installed orifice tube. It may be installed backwards.
Correction (http://elcovaforums.com/forums/#ss3-1360249)
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 (http://elcovaforums.com/forums/#ss4-1360249)
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.
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).
H2Finally
06-15-2006, 05:23 AM
My problem is the opposite. Never had a problem with AC, then while at the dealer for some other issue, they turned the tube around because of the bulletin, and have had non-stop issue of AC not cooling enough since (this was last summer).
They've double-checked the tube, recharged the AC, increased the pressure, decreased the pressure, triple-checked the tube -- but they refused to put it back backwards because of the damn bulletin. Then we hit cool weather and I let the issue go.
HOPING it doesn't come back this summer...
dochummer
06-15-2006, 05:57 AM
I had my condensor replaced near the end of my warranty period. Then it was winter, so I didn't have to use it....I've noticed this summer that it doesn't seem to be cooling as well as it used to...like you said, especially on the hot days. So, anybody have a diagram on how to check this yourself and turn it around?
OrangeCrush
06-15-2006, 12:04 PM
I had my condensor replaced near the end of my warranty period. Then it was winter, so I didn't have to use it....I've noticed this summer that it doesn't seem to be cooling as well as it used to...like you said, especially on the hot days. So, anybody have a diagram on how to check this yourself and turn it around?
Doc,
I think the orifice tube is in between the high and low schrader valves. There is a union nut that you can unscrew and pull the lines apart. The valve will fit either way...
However, unless you have the ability to evacuate and recharge the system, you'll need to take it to a mechanic to have it done. Undoing the lines to take the orifice tube will let the freon escape out into the atmosphere.
Ree,
Until you posted the bulletin, I hadn't realized that the hissing sound was also caused from the orifice tube. I have always noticed I could shut the truck off and it sounded like it was releasing presssure... so hopefully that will be a benefit too.
H2finally,
Do yourself a favor. Take the truck to an AC guy and have them put an actual set of gauges on the system. My techs in my bodyshop use a machine to evacuate and recharge. You set the amount using a digital readout and the machine will install the correct amount.
Point is, I know I have thrown a set of gauges on afterwards and the pressure is wrong and the system doesn't cool correctly.
The high side pressure should run about 230-240 lbs and the low side should be 35-40 lbs. Alot of this depends on the outside temp and other relative factors.
What made me suspect something was wrong (other than it just plain sucked...lol) was my low side was at 60-70 lbs... usually that means the compressor is on its way out.
HTH's,
Mark
SnakeH2
06-15-2006, 12:16 PM
Never had a problem with the a/c (touch wood)....
He said touch wood:p
devilsfan
06-15-2006, 02:13 PM
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
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
06-15-2006, 06:22 PM
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
06-15-2006, 10:52 PM
Um, it's a snowflake with a slash through it, meaning turn off AC when you select it.
x2:)
PARAGON
06-15-2006, 11:16 PM
I don't see no stinkin arrow
PARAGON
06-15-2006, 11:22 PM
BTW, here is an orifice tube
OrangeCrush
06-15-2006, 11:45 PM
I don't see no stinkin arrow
Actually, I think that's the problem. There is no arrow. There is suppose to be one... that's probably how they got put in backwards.
Mark
PARAGON
06-15-2006, 11:54 PM
Do you know if it's visible from outside, that it's in backwards. If so, can you take a pic of yours for comparison.
dochummer
06-16-2006, 03:06 AM
Do you know if it's visible from outside, that it's in backwards. If so, can you take a pic of yours for comparison.
translation: Can you show me a real pic of where to look for the @$%@ thing!?! :D
OrangeCrush
06-16-2006, 11:29 AM
translation: Can you show me a real pic of where to look for the @$%@ thing!?! :D
Thanks Doc,
I was starting to think it was me :o
Mark
PARAGON
06-16-2006, 01:00 PM
Thanks Doc,
I was starting to think it was me :o
MarkActually, no. I'm serious. The bulletin says to inspect to determine if it is in backwards. There's no arrow, so I have no idea if it's in backwards or not.
If there is a manner in which one might determine it's orientation from the outside without breaking that nut, it would be nice to have a picture of someone's whom we know is installed correctly to be used for comparison.
Ree, can you take a pic of yours?
Actually, no. I'm serious. The bulletin says to inspect to determine if it is in backwards. There's no arrow, so I have no idea if it's in backwards or not.
If there is a manner in which one might determine it's orientation from the outside without breaking that nut, it would be nice to have a picture of someone's whom we know is installed correctly to be used for comparison.
Ree, can you take a pic of yours? Sure.
I think I got the right parts in these shots. Funny that the bend and ports don't quite match the diagram from the manuals.
It doesn't appear that there's a simple visual indicator. Must be the prolonged hissing after shutoff is the key indicator to go to the trouble of evacuating the system to do the check.
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PARAGON
06-16-2006, 02:02 PM
Thanks,
I figured as much. I was hoping there was something else that would be more indicative of it being in backwards. I couldn't tell that there was going to be anything on mine, and thought maybe I did have the expansion tube at all.
dochummer
06-16-2006, 05:05 PM
So, really, there's no way to tell?
My problem is the opposite. Never had a problem with AC, then while at the dealer for some other issue, they turned the tube around because of the bulletin, and have had non-stop issue of AC not cooling enough since (this was last summer).
They've double-checked the tube, recharged the AC, increased the pressure, decreased the pressure, triple-checked the tube -- but they refused to put it back backwards because of the damn bulletin. Then we hit cool weather and I let the issue go.
HOPING it doesn't come back this summer...Maybe they read the instructions backwards.:eek:
devilsfan
06-16-2006, 07:47 PM
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
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
You're right about the label on the button. But when you select it (i.e. it lights up), the display shows a snowflake with a slash through it. Definitely a usability flaw, but yours is functioning "backward" like everyone elses.
H2 Bill
06-16-2006, 09:33 PM
I have an '03 too and if the snowflake is showing on the display, the AC is off and just blowing air. When the air is on and freezing me out there is no snowflake showing.
I have an '03 too and if the snowflake is showing on the display, the AC is off and just blowing air. When the air is on and freezing me out there is no snowflake showing.
All I was saying is that when the AC is off, the display doesn't show a snowflake; it shows a snowflake with a slash through it:
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H2 Bill
06-16-2006, 10:03 PM
I stand corrected...(forgot about the slash). There is still no snowflake (with slash through it) when it is on.
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
06-17-2006, 04:38 AM
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
06-17-2006, 05:07 AM
I have an '05. Snowflake when AC on; nothing when it's off.
devilsfan
06-18-2006, 07:00 PM
Must be a GM thing. The Slade has the same as the later model H2s - snowflake shown when the AC is on.
Stacy
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
06-19-2006, 08:51 PM
so if i have the hissing after shut off should i simply contact my local hummer dealer to have this checked out?
OrangeCrush
06-20-2006, 01:55 AM
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
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
Ditto. If it's an '03, AC doesn't work well, and it hisses after turning the truck off, then have it checked. Mine was hissing quite a bit after shutting it off. After the fix, it still hisses a little, but it's for much shorter duration.
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