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Problem with dash air conditioning refurbishement [message #284698] Wed, 12 August 2015 13:43 Go to next message
rjw   United States
Messages: 697
Registered: September 2005
Karma: 4
Senior Member
Kind of a long story.

Last year, I noticed that my dash air was no longer cooling. In the past I merely topped it of with HC-12a from the 30 lb cylinder I bought a few years ago. This time it would not take a charge and I noticed that the both high and low pressures were the same. I assumed a bad compressor.

I decided that I should go with a new Sanden A-6 for numerous reasons. I ordered the compressor and receiver dryer from Applied and bought an expansion valve locally.

Well I never got around to installing the parts until this year. Reason being I ran out of time last year getting ready to go to the Chippewa Falls rally. Then the ground froze and the water outside turned to ice causing me to postpone the project.

Last week I finally got around to it. I did the following:
1) removed the old compressor, receiver dryer and expansion valve.
2) per Applied's recommendation, I drained the oil from the new compressor and refilled with 8 oz of Polyol Ester oil (retrofit oil). Which is supposed to be compatible with all types of oil.
3) flushed out all lines, condenser and evaporator with the A/C flush kit I bought.
4) installed the compressor, new receiver dryer, expansion valve and old hoses with new O rings.
5) ran my vacuum pump on the system for 3 hours and checked for leaks overnight.
6) connected the 30# HC-12a bottle to the gauge set.
7) started up the engine
Cool shorted the pressure switch connector to start the pump and heard it running
9) got it up to 30PSI low

RESULT
Instead of the comforting blast of cool air I got nothing. Noticed that both high and low sides had the same pressure reading.

Added more HC-12a and still nothing and both sides have same pressure. Was the new pump bad out of the box?

Also, noticed that when I loosened up the low side connector to let some HC-12a out, I got foamy oil. That never happened before. Got more oil when I disconnected the bottle and gauge set.

What did I do wrong? Add too much oil?

I am annoyed that I will more than likely have to buy another compressor (out of warranty?) and another receiver dryer.

These things are not that complicated.


Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com

Roller Cam 455, TBI+EBL, 3.42 FD, 4 Bag, Macerator, Lenzi (brakes, vacuum system, front end stuff), Manny Tranny, vacuum step, Tankless + OEM water heaters.
Re: [GMCnet] Problem with dash air conditioning refurbishement [message #284703 is a reply to message #284698] Wed, 12 August 2015 15:06 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member
Richard
There is a good chance that something is clogged. I would have guessed an expansion valve but you say that you put on a new one.
I would suggest that you take things apart and try to blow compressed air through each hose and each component to see if one is clogged.

By the way 30 psi is way too high for the low side if you are using HC12a. However, if both sides are at the same pressure the suction side was probably not drawing down the low pressure side anyway.

Emery Stora

> On Aug 12, 2015, at 12:43 PM, RJW wrote:
>
> Kind of a long story.
>
> Last year, I noticed that my dash air was no longer cooling. In the past I merely topped it of with HC-12a from the 30 lb cylinder I bought a few
> years ago. This time it would not take a charge and I noticed that the both high and low pressures were the same. I assumed a bad compressor.
>
> I decided that I should go with a new Sanden A-6 for numerous reasons. I ordered the compressor and receiver dryer from Applied and bought an
> expansion valve locally.
>
> Well I never got around to installing the parts until this year. Reason being I ran out of time last year getting ready to go to the Chippewa Falls
> rally. Then the ground froze and the water outside turned to ice causing me to postpone the project.
>
> Last week I finally got around to it. I did the following:
> 1) removed the old compressor, receiver dryer and expansion valve.
> 2) per Applied's recommendation, I drained the oil from the new compressor and refilled with 8 oz of Polyol Ester oil (retrofit oil). Which is
> supposed to be compatible with all types of oil.
> 3) flushed out all lines, condenser and evaporator with the A/C flush kit I bought.
> 4) installed the compressor, new receiver dryer, expansion valve and old hoses with new O rings.
> 5) ran my vacuum pump on the system for 3 hours and checked for leaks overnight.
> 6) connected the 30# HC-12a bottle to the gauge set.
> 7) started up the engine
> 8) shorted the pressure switch connector to start the pump and heard it running
> 9) got it up to 30PSI low
>
> RESULT
> Instead of the comforting blast of cool air I got nothing. Noticed that both high and low sides had the same pressure reading.
>
> Added more HC-12a and still nothing and both sides have same pressure. Was the new pump bad out of the box?
>
> Also, noticed that when I loosened up the low side connector to let some HC-12a out, I got foamy oil. That never happened before. Got more oil when
> I disconnected the bottle and gauge set.
>
> What did I do wrong? Add too much oil?
>
> I am annoyed that I will more than likely have to buy another compressor (out of warranty?) and another receiver dryer.
>
> These things are not that complicated.
> --
> Richard
> 76 Palm Beach
> SE Michigan
> www.PalmBeachGMC.com
>
>
> Coop Roller Cam 455, Howell TBI + EBL, 3.42 FD, Quadra Bag, Macerator, Manny Tranny etc.
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


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Re: [GMCnet] Problem with dash air conditioning refurbishement [message #284707 is a reply to message #284698] Wed, 12 August 2015 15:52 Go to previous messageGo to next message
powerjon is currently offline  powerjon   United States
Messages: 2446
Registered: January 2004
Karma: 5
Senior Member
Richard see my comments below.

JR Wright
GMC Great Laker MHC
GMC Eastern States
GMCGL Tech Editor
GMCMHI
78 GMC Buskirk 30’ Stretch
1975 GMC Avion (Under Reconstruction)
Michigan

> On Aug 12, 2015, at 2:43 PM, RJW wrote:
>
> Kind of a long story.
>
> Last year, I noticed that my dash air was no longer cooling. In the past I merely topped it of with HC-12a from the 30 lb cylinder I bought a few
> years ago. This time it would not take a charge and I noticed that the both high and low pressures were the same. I assumed a bad compressor.
>
> I decided that I should go with a new Sanden A-6 for numerous reasons. I ordered the compressor and receiver dryer from Applied and bought an
> expansion valve locally.
To confirm that you installed a Sanden S6 compressor or the Sanden 508 type compressor?
>
> Well I never got around to installing the parts until this year. Reason being I ran out of time last year getting ready to go to the Chippewa Falls
> rally. Then the ground froze and the water outside turned to ice causing me to postpone the project.
>
> Last week I finally got around to it. I did the following:
> 1) removed the old compressor, receiver dryer and expansion valve.
> 2) per Applied's recommendation, I drained the oil from the new compressor and refilled with 8 oz of Polyol Ester oil (retrofit oil). Which is
> supposed to be compatible with all types of oil.

8 oz of the oil might be too much as the Sanden is smaller in size. If you added more than your took out then you may have too much oil in the system.

I have not used this oil, but according to the literature it is compatible with R134 & R12 and Duracool refrigerants in a clean system, no cross contamination of oils.

https://en.wikipedia.org/wiki/Polyolester

How much oil did you drain out of the new compressor? What was the recommended amount of oil for the compressor? The Evap, condenser and Rec/Dry are typically 1 oz each.

http://www.sanden.com/objects/Compressor_Installation_Instructions.pdf

> 3) flushed out all lines, condenser and evaporator with the A/C flush kit I bought.
> 4) installed the compressor, new receiver dryer, expansion valve and old hoses with new O rings.
> 5) ran my vacuum pump on the system for 3 hours and checked for leaks overnight.
> 6) connected the 30# HC-12a bottle to the gauge set.
> 7) started up the engine
> 8) shorted the pressure switch connector to start the pump and heard it running
> 9) got it up to 30PSI low

30# is way too high a pressure on the Low side for HC-12A or Duracool. You kind of want to sneak up on about 24# @ 1500 RPM as the sweet spot. My guess is that you have a plug somewhere in the system. Your going to need to take it back apart and blow thru each hose and the condenser and evaporator and thru the rec/dry. The rec/dry can be reused if if blow thru ok.
>
> RESULT
> Instead of the comforting blast of cool air I got nothing. Noticed that both high and low sides had the same pressure reading.
>
> Added more HC-12a and still nothing and both sides have same pressure. Was the new pump bad out of the box?
>
> Also, noticed that when I loosened up the low side connector to let some HC-12a out, I got foamy oil. That never happened before. Got more oil when
> I disconnected the bottle and gauge set.
>
> What did I do wrong? Add too much oil?
As a guess it might be yes if you got oil foam and it is tough compressing a liquid.
>
> I am annoyed that I will more than likely have to buy another compressor (out of warranty?) and another receiver dryer.
Shouldn’g be ant thing wrong with the Rec/dry/
>
> These things are not that complicated.
> --
> Richard
> 76 Palm Beach
> SE Michigan
> www.PalmBeachGMC.com
>


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J.R. Wright
GMC GreatLaker
GMC Eastern States
GMCMI
78 30' Buskirk Stretch
75 Avion Under Reconstruction
Michigan
Re: Problem with dash air conditioning refurbishement [message #284742 is a reply to message #284698] Thu, 13 August 2015 01:02 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
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Registered: July 2004
Location: Minden nevada
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Senior Member
Are you certain the clutch is engaged? If the clutch is in fact engaged and your Gage's are connected properly and the manifold valves are closed I would say your compressor has bad valves or broken internal parts. If the expansion valve is restricted closed the low side will be in a vacuum and the high side will be over 100 . If the expansion valve is missing its internals the pressure would be pretty much equal but I doubt this.

Roy Keen Minden,NV 76 X Glenbrook
Re: Problem with dash air conditioning refurbishement [message #284775 is a reply to message #284698] Thu, 13 August 2015 10:15 Go to previous messageGo to next message
Chris Tyler is currently offline  Chris Tyler   United States
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Registered: September 2013
Location: Odessa FL
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Senior Member
I would think a restriction would cause a pressure differential or possibly deadheading the compressor, whereas NO restriction [ie bad exp valve] would leave it equal on both sides

76 Glenbrook
Re: Problem with dash air conditioning refurbishement [message #284781 is a reply to message #284775] Thu, 13 August 2015 10:44 Go to previous messageGo to next message
Keith V is currently offline  Keith V   United States
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Registered: March 2008
Location: Mounds View,MN
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Senior Member
make sure the clutch is actually engaging. You cannot tell by looking at it if it's like mine


Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
Re: Problem with dash air conditioning refurbishement [message #284786 is a reply to message #284742] Thu, 13 August 2015 11:40 Go to previous messageGo to next message
rjw   United States
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Registered: September 2005
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Senior Member
Thanks everyone for the feedback.

To confirm, it is supposed to be a S6 compressor. I drained out ~5 oz of oil and Nick at Applied said to refill with 8 oz of oil. They apparently find a lot of variability with the amount of oil that each compressor contains from the factory.

When I opened the valve of my refrigerant bottle, the gauge went to 30 PSI in just a few seconds. I think it should have taken longer to put in a full charge. With the pump running I applied a short burst that took it to close to 50 on both sides. That's when I decided to let some HC-12 out. At that time I noticed foamy oil coming out with the refrigerant. I let out just a little and went down to 25 psi. With no cooling and no clue as to what was was wrong, I called it quits. I had already spent too much time and had to get ready to go on a GMC trip the next day.

I am certain that the compressor does engage. I can hear it running when I use a paperclip to jump the contacts in the connector going to the pressure switch.

From what I've read here and other online sources it appears that if both sides have equal or almost equal pressure, the compressor is probably bad. That seems to be my situation.

Was it bad out of the box or did I do something to make it fail?

I sure hate to put out another $350 for a new compressor when the one I had was still new but apparently out of warranty. That will teach me to procrastinate on my projects with new parts.

Anyway, before I jump the gun and buy another compressor, I will open everything up and flush all the lines and other components as well as drain the compressor and refill. However, I suspect that won't change things.


Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com

Roller Cam 455, TBI+EBL, 3.42 FD, 4 Bag, Macerator, Lenzi (brakes, vacuum system, front end stuff), Manny Tranny, vacuum step, Tankless + OEM water heaters.
Re: Problem with dash air conditioning refurbishement [message #284793 is a reply to message #284786] Thu, 13 August 2015 12:32 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
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Location: Spanish Fort, AL
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Senior Member
"S6", is this the designator for the Sanden replacement for the A6?
Chasing a dead air compressor.
Tom, MS II


2012 Phoenix Cruiser model 2552 KA4CSG
Re: Problem with dash air conditioning refurbishement [message #284808 is a reply to message #284698] Thu, 13 August 2015 16:41 Go to previous messageGo to next message
zhagrieb is currently offline  zhagrieb   United States
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Location: Portland Oregon
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Senior Member
I replaced my expansion valve with one that "looked right" only to find it worked the reverse of what was needed. Found correct valve and all OK. Get one from Jim K, it will be correct. Glenn

Glenn Giere, Portland OR, K7GAG '73 "Moby the Motorhome" 26'

[Updated on: Thu, 13 August 2015 16:42]

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Re: Problem with dash air conditioning refurbishement [message #284820 is a reply to message #284698] Thu, 13 August 2015 19:17 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Location: Woodstock, IL
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After draining the old oil, don't you need to flush or the 2 oils will mix and make glop?

John Lebetski
Woodstock, IL
77 Eleganza II
Re: Problem with dash air conditioning refurbishement [message #284827 is a reply to message #284820] Thu, 13 August 2015 21:15 Go to previous messageGo to next message
Scott Nutter is currently offline  Scott Nutter   United States
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I've got to hand it to you gents, it never ceases me the amount of knowledge almost every one here has on almost every system. Growing up I never had AC. Let be home or auto. So needless to say, I could rebuild a 289, 327, 350, 390, or 396..but I would only be qualified to sweep the floors at a AC shop. I envy you guys..........keep passing the knowledge!!

Scott Nutter 1978 Royale Center Kitchen, Patterson 455, switch pitch tranny, 3.21 final drive, Quad bags, Dave Lenzi super duty mid axle disc brakes, tankless water heater, everything Lenzi. Alex Ferrera installed MSD Atomic EFI Houston, Texas
Re: Problem with dash air conditioning refurbishement [message #284831 is a reply to message #284820] Thu, 13 August 2015 21:54 Go to previous messageGo to next message
rjw   United States
Messages: 697
Registered: September 2005
Karma: 4
Senior Member
JohnL455 wrote on Thu, 13 August 2015 20:17
After draining the old oil, don't you need to flush or the 2 oils will mix and make glop?

It is my understanding that there are basically 3 types of AC oil:
1) mineral oil which is used with R12
2) PAG oil used with R134 which is incompatible with mineral oil.
3) Polyol Ester oil (aka retrofit oil) which is compatible with either of the above.

I used Polyol Ester oil for my attempted AC installation.


Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com

Roller Cam 455, TBI+EBL, 3.42 FD, 4 Bag, Macerator, Lenzi (brakes, vacuum system, front end stuff), Manny Tranny, vacuum step, Tankless + OEM water heaters.
Re: [GMCnet] Problem with dash air conditioning refurbishement [message #284833 is a reply to message #284827] Thu, 13 August 2015 22:00 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Location: Sydney, Australia
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Scott,

It is interesting the way "we" are perceived, to some we're "grumpy old men" and others "envy us."

I guess you could say we're a bunch of old wise guys! ;-)

Regards,
Rob M.
The Pedantic Mechanic


-----Original Message-----
From: Scott Nutter

I've got to hand it to you gents, it never ceases me the amount of knowledge almost every one here has on almost every system.
Growing up I never had AC. Let be home or auto. So needless to say, I could rebuild a 289, 327, 350, 390, or 396..but I would only
be qualified to sweep the floors at a AC shop. I envy you guys..........keep passing the knowledge!!
--
Scott


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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: Problem with dash air conditioning refurbishement [message #284845 is a reply to message #284698] Fri, 14 August 2015 08:10 Go to previous messageGo to next message
Rick Williams is currently offline  Rick Williams   United States
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Registered: July 2004
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Senior Member
I looked at Sanden's website and did not find any information on the S6. CoolPro claims to have developed it (http://www.s6compressor.com/products.html) and I think they are a subsidiary of Sanden but that is not easy to determine. I installed a Sanden SD7H15 about 5 years ago and it works fine. It is a 7 piston 155cc compressor. The A6 is 220cc as is the S6. The S6 is a 10 piston compressor. I am not sure why I spent time on this issue today because mine works fine but I guess I was just curious as to the origin of the S6. It was not an option when I pieced together my system based on information from Ken Henderson's Sanden conversion. If anyone is interested in a SD7H15 conversion, I can provide details. And Rob, I don't know which one I prefer, "wise guy" or "grumpy old man" but I am just glad to be here.

Rick


Rick Williams
Bliss, Michigan
1978 Eleganza II
Re: Problem with dash air conditioning refurbishement [message #285313 is a reply to message #284698] Tue, 18 August 2015 15:35 Go to previous messageGo to next message
rjw   United States
Messages: 697
Registered: September 2005
Karma: 4
Senior Member
rjw wrote on Wed, 12 August 2015 14:43
Kind of a long story.

Last year, I noticed that my dash air was no longer cooling. In the past I merely topped it of with HC-12a from the 30 lb cylinder I bought a few years ago. This time it would not take a charge and I noticed that the both high and low pressures were the same. I assumed a bad compressor.

I decided that I should go with a new Sanden A-6 for numerous reasons. I ordered the compressor and receiver dryer from Applied and bought an expansion valve locally.

Well I never got around to installing the parts until this year. Reason being I ran out of time last year getting ready to go to the Chippewa Falls rally. Then the ground froze and the water outside turned to ice causing me to postpone the project.

Last week I finally got around to it. I did the following:
1) removed the old compressor, receiver dryer and expansion valve.
2) per Applied's recommendation, I drained the oil from the new compressor and refilled with 8 oz of Polyol Ester oil (retrofit oil). Which is supposed to be compatible with all types of oil.
3) flushed out all lines, condenser and evaporator with the A/C flush kit I bought.
4) installed the compressor, new receiver dryer, expansion valve and old hoses with new O rings.
5) ran my vacuum pump on the system for 3 hours and checked for leaks overnight.
6) connected the 30# HC-12a bottle to the gauge set.
7) started up the engine
Cool shorted the pressure switch connector to start the pump and heard it running
9) got it up to 30PSI low

RESULT
Instead of the comforting blast of cool air I got nothing. Noticed that both high and low sides had the same pressure reading.

Added more HC-12a and still nothing and both sides have same pressure. Was the new pump bad out of the box?

Also, noticed that when I loosened up the low side connector to let some HC-12a out, I got foamy oil. That never happened before. Got more oil when I disconnected the bottle and gauge set.

What did I do wrong? Add too much oil?

I am annoyed that I will more than likely have to buy another compressor (out of warranty?) and another receiver dryer.

These things are not that complicated.

I solved my problem!

Turns out that it was my gauge set that was at fault. The shutoff valve for the high side was not shutting off. That caused the pressures on both sides to be the same (making me think bad compressor) with the low side valve open and I thought the high side closed. I fixed the high side valve so that it would close completely. After that I was able to bring up a charge, with the engine running to 25 PSI low side which I think is optimal?

I now get ~40 degree air from the center vent inside with outside temp being 85.

Now to make sure I don't have leaks. I hope I don't have a leak inside the box because I hate to take that apart again.


Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com

Roller Cam 455, TBI+EBL, 3.42 FD, 4 Bag, Macerator, Lenzi (brakes, vacuum system, front end stuff), Manny Tranny, vacuum step, Tankless + OEM water heaters.
Re: Problem with dash air conditioning refurbishement [message #285315 is a reply to message #284698] Tue, 18 August 2015 15:44 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Registered: October 2006
Location: Woodstock, IL
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Senior Member
Good thing you didn't explode the can. Glad you figured it out.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: Problem with dash air conditioning refurbishement [message #285322 is a reply to message #285315] Tue, 18 August 2015 17:47 Go to previous message
rjw   United States
Messages: 697
Registered: September 2005
Karma: 4
Senior Member
JohnL455 wrote on Tue, 18 August 2015 16:44
Good thing you didn't explode the can. Glad you figured it out.

I stopped before putting much of a charge in the system because I was concerned with the equal pressure and no cooling. There was never more than 50 psi on the high side (and low side). But a possible explosion would certainly be a real concern with the high side open and the compressor pumping the high side (and the refrigerant container) up to hundreds of PSI.

Scary to think about. I am glad I stopped as soon as I realized that things didn't look right.


Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com

Roller Cam 455, TBI+EBL, 3.42 FD, 4 Bag, Macerator, Lenzi (brakes, vacuum system, front end stuff), Manny Tranny, vacuum step, Tankless + OEM water heaters.
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