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AC Gauges [message #201464] Tue, 12 March 2013 21:32 Go to next message
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Re: [GMCnet] AC Gauges [message #201466 is a reply to message #201464] Tue, 12 March 2013 21:40 Go to previous messageGo to next message
hnielsen2 is currently offline  hnielsen2   United States
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email Steve Ferguson.
He is up on the A/C stuff.

All is well with my Lord
Howard
On Mar 12, 2013, at 7:32 PM, Joe Crutchfield <joe.crutchfield@hotmail.com> wrote:

>
>
> I have read several older threads regarding AC gauges and other AC topics and this is a question for some of the experienced AC folks.
>
> Even though I am a fairly good mechanic, electrician, and other wise handyman, I have no experience with AC - except enjoying its benefits on a hot day. I would like to at least learn enough to check and add refrigerant. I have three immediate projects that need AC expertise - my GMC, my new Vintage Air system I instaled on my 1972 pickup I am rebuilding, and a new AC unit for the house.
>
> I found this set of AC gauges and wondered if I could get feedback on whether they will do the job for the various refrigerants I will be needing. A cheap set at Harbor Freight is selling for about $60. now and it looks like they are for 134a only.
>
> Here is the set:
>
> http://www.hvacr-tools.com/product/bacharach-2002-5000-manifold-set-with-60-ryb-hoses-r-12-22-134a
>
> If this set is not what I need, I would appreciate your advice on what you think I need.
> --
> Joe Crutchfield,
> Watertown, TN,
> 77 Royale by Coachman, Rear Bath, 455, 3.07,
>
> "Strangers are just friends I haven't met yet" - Will Rogers.
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All is well with my Lord
Re: [GMCnet] AC Gauges [message #201468 is a reply to message #201464] Tue, 12 March 2013 21:46 Go to previous messageGo to next message
Gary Worobec is currently offline  Gary Worobec   United States
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Joe, you will also need a vacuum pump as well to both checks for leaks
before you fill the system and evacuate the system as well. Sometimes you
can find a deal on the gauges and pump as a set. I got this set and just
used it a couple of days ago on the coach. The next use will be on a Vintage
or Old air system for my 35 Dodge pickup later in the year.

http://tinyurl.com/abm5n3t


Thanks,

Gary and Joanne Worobec
1973 GMC Glacier
Anza, CA





-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Joe Crutchfield
Sent: Tuesday, March 12, 2013 7:32 PM
To: gmclist@temp.gmcnet.org
Subject: [GMCnet] AC Gauges



I have read several older threads regarding AC gauges and other AC topics
and this is a question for some of the experienced AC folks.

Even though I am a fairly good mechanic, electrician, and other wise
handyman, I have no experience with AC - except enjoying its benefits on a
hot day. I would like to at least learn enough to check and add
refrigerant. I have three immediate projects that need AC expertise - my
GMC, my new Vintage Air system I instaled on my 1972 pickup I am rebuilding,
and a new AC unit for the house.

I found this set of AC gauges and wondered if I could get feedback on
whether they will do the job for the various refrigerants I will be needing.
A cheap set at Harbor Freight is selling for about $60. now and it looks
like they are for 134a only.

Here is the set:

http://www.hvacr-tools.com/product/bacharach-2002-5000-manifold-set-with-60-
ryb-hoses-r-12-22-134a

If this set is not what I need, I would appreciate your advice on what you
think I need.
--
Joe Crutchfield,
Watertown, TN,
77 Royale by Coachman, Rear Bath, 455, 3.07,

"Strangers are just friends I haven't met yet" - Will Rogers.
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Re: [GMCnet] AC Gauges [message #201477 is a reply to message #201468] Tue, 12 March 2013 22:36 Go to previous messageGo to next message
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Re: [GMCnet] AC Gauges [message #201480 is a reply to message #201477] Tue, 12 March 2013 23:09 Go to previous messageGo to next message
Gary Worobec is currently offline  Gary Worobec   United States
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I totally removed the original system and put in a Danhard 24,000 BTU A/C
unit. It punches through the firewall and sits almost on top of the
radiator. New condenser, lines, drier but use a rebuilt OEM A6 lump for a
compressor. The gauge set I have is only for R-134. The system seems to work
fine. Lots of cold air now with no restrictions inside the dash. Just blasts
straight into the cockpit. I think you just need the correct adapters for
the gauges. The gauges and pump ought to be universal in application I would
think.


Thanks,

Gary and Joanne Worobec
1973 GMC Glacier
Anza, CA




-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Joe Crutchfield
Sent: Tuesday, March 12, 2013 8:37 PM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] AC Gauges



Thanks Howard and Gary.

Gary, do you know if these gauges will handle the different refrigerants I
will be using for auto and residential AC? My current AC system is 12 years
old and uses R22 - I think. The package AC unit I have been looking at for
the house says it is precharged with R410. Vintage Air told me to use 134a
in their system - so the gauges will work for that project.

Do you have the original AC system on your GMC and did you replace the
refrigerant with 134A?

Thanks
--
Joe Crutchfield,
Watertown, TN,
77 Royale by Coachman, Rear Bath, 455, 3.07,

"Strangers are just friends I haven't met yet" - Will Rogers.
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Re: AC Gauges [message #201482 is a reply to message #201464] Wed, 13 March 2013 00:42 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Here is the deal.

A set gauges is a set of gauges they do not know the difference between the various refrigerants. If you are reading pressure it is all the same. Some gauge sets have marks on the scale for the various pressure ranges for the various refrigerants. Who cares? All you want to do is read pressures.

The big difference in gauges for sale today is in the hose connection types. R12 (OEM GMC) uses a schrader type connection on both the high and low pressure sides. R-134 uses and different style and needs a different pair of hose connections.

So what do you want to do? Well get a set of gauges and buy a pair of adapters to screw on the hoses to match the opposite type. My gauges were originally for R-12 with schrader type ends. With those ends I can connect to any R-12 and R-22 connections direct. I also can connect direct to a vacuum pump or a large container of Duracool, r-12, r-22 or r-134 with the 3rd hose.

If I am doing a R-134 vehicle I have a pair of adapters that screw on the hose ends and now I can connect to the r-134 connections on a modern vehicle.

So if you buying a set of gauges, just make sure you also get a set of adapters to match the other connection types and you will be OK.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: AC Gauges [message #201484 is a reply to message #201482] Wed, 13 March 2013 00:46 Go to previous messageGo to next message
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Re: AC Gauges [message #201492 is a reply to message #201484] Wed, 13 March 2013 05:34 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
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Consider using Duracool in the GMC system. Many have changed over and are happy with the results. For a evacuated stock OEM, you will need a little less than 3 cans. Mine actually puts out cold air with the change over.
Search the site for deeper detail.
Tom, MS iI


2012 Phoenix Cruiser model 2552 KA4CSG

[Updated on: Wed, 13 March 2013 05:34]

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Re: [GMCnet] AC Gauges [message #201502 is a reply to message #201482] Wed, 13 March 2013 07:21 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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One additional important fact: Duracool (AKA HC-12a) uses R-134a-type
connectors. EPA rules supposedly require change to from R-12 to R-134a
type vehicle connectors before installing HC-12a.

Ken H.

On Wed, Mar 13, 2013 at 1:42 AM, Ken Burton wrote:

>
>
> Here is the deal.
>
> A set gauges is a set of gauges they do not know the difference between
> the various refrigerants. If you are reading pressure it is all the same.
> Some gauge sets have marks on the scale for the various pressure ranges
> for the various refrigerants. Who cares? All you want to do is read
> pressures.
>
> The big difference in gauges for sale today is in the hose connection
> types. R12 (OEM GMC) uses a schrader type connection on both the high and
> low pressure sides. R-134 uses and different style and needs a different
> pair of hose connections.
>
> So what do you want to do? Well get a set of gauges and buy a pair of
> adapters to screw on the hoses to match the opposite type. My gauges were
> originally for R-12 with schrader type ends. With those ends I can connect
> to any R-12 and R-22 connections direct. I also can connect direct to a
> vacuum pump or a large container of Duracool, r-12, r-22 or r-134 with the
> 3rd hose.
>
> If I am doing a R-134 vehicle I have a pair of adapters that screw on the
> hose ends and now I can connect to the r-134 connections on a modern
> vehicle.
>
> So if you buying a set of gauges, just make sure you also get a set of
> adapters to match the other connection types and you will be OK.
> --
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: AC Gauges [message #201504 is a reply to message #201482] Wed, 13 March 2013 07:33 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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Ken Burton wrote on Wed, 13 March 2013 00:42

... R12 (OEM GMC) uses a schrader type connection on both the high and low pressure sides. R-134 uses and different style and needs a different pair of hose connections. ...


I will embarrass my self and admit to you that the schrader valve R12 R24 hoses CAN be installed backward. Only one end will operate the schrader valve.

I couldn't figure out why my system wasn't taking a charge and asked a buddy to bring his gauges over. His worked and while the system charged he asked what happened to mine...looked at it a second and informed me I was a dumbass. Embarassed Embarassed Embarassed DUH!


Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: [GMCnet] AC Gauges [message #201512 is a reply to message #201464] Wed, 13 March 2013 08:15 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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Senior Member
Joe,

Do an eBay search and you'll find good a good quality set of gages there, I've seen Snap on gages sell CHEAP!

I reckon either one of these Harbor Freight pumps are OK:

Currently on sale for $89.99:
http://www.harborfreight.com/25-cfm-vacuum-pump-98076.html\
•75 micron/10 Pascal maximum vacuum

Currently on sale for $139.99:
http://www.harborfreight.com/two-stage-3-cfm-air-vacuum-pump-66466.html
•Two stage pump draws vacuum down to 25 micron

I would not buy one of these:

http://www.harborfreight.com/air-vacuum-pump-with-r134a-and-r12-connectors-96677.html

•Vacuum level: 28.3" of mercury at sea level (a hard vacuum at sea level would be 29.92" of mercury)

Regards,
Rob M.
 
-----Original Message-----
From: Joe Crutchfield

I have read several older threads regarding AC gauges and other AC topics and this is a question for some of the experienced AC
folks.

Even though I am a fairly good mechanic, electrician, and other wise handyman, I have no experience with AC - except enjoying its
benefits on a hot day. I would like to at least learn enough to check and add refrigerant. I have three immediate projects that
need AC expertise - my GMC, my new Vintage Air system I instaled on my 1972 pickup I am rebuilding, and a new AC unit for the house.


I found this set of AC gauges and wondered if I could get feedback on whether they will do the job for the various refrigerants I
will be needing. A cheap set at Harbor Freight is selling for about $60. now and it looks like they are for 134a only.

Here is the set:

http://www.hvacr-tools.com/product/bacharach-2002-5000-manifold-set-with-60-ryb-hoses-r-12-22-134a

If this set is not what I need, I would appreciate your advice on what you think I need.
--
Joe

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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: AC Gauges [message #201513 is a reply to message #201464] Wed, 13 March 2013 08:36 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Joe,

Actual usable advice, look at the Hazard Fright set 92649. The couplers screw onto the hoses with the same thread as is the standard R-134a (1/2-16 Acme). This makes the hoses easily serviceable. The couplers also have an external service valve depressor. This means you can get the coupler locked on the service fitting and then open the internal schrader valve. This is a really good feature. Just get the colors to match and be sure the attachments are tight when you assemble the set.

Gauges is gauges - Truth... They may have different vapor pressure scales, but that really does not matter very much. The problem is the connectors and hoses. Automotive use the new silly connectors. Those are still automotive only. The 1/2 Acme connector is getting some traction in the real world. So, while I still have my old gauge set hanging where it has all these years, I also have a newer set that will fit the new access fittings. What a PITA, and all because a guy had an equation upside down.

The Duracool and other HC-12a manufactures are fitting the cans with the R-134r standard thread. So, unless you have some special need, get a manifold and pump that are setup for 134.

It will be to your advantage to get the adapters that convert the old 1/4 flare service access fittings to the R-134 version for anything you are working on. Only a very few of us old geezers can even get on the old fitting these days and not many of us even still have any R-12 stock.

Apart from this whole thing being and unnecessary deception, it is much more smoke than mirror. The new connector for R-134a was to "Prevent the inadvertent release of refrigerant into the environment". (Actually, they prevent a good reefer guy from minimizing the release.)

Matt - going back to preparing for departure for Dothan.


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: [GMCnet] AC Gauges [message #201549 is a reply to message #201482] Wed, 13 March 2013 10:49 Go to previous messageGo to next message
k2gkk is currently offline  k2gkk   United States
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I am bringing my gauges and a supply of DuraCool to Dothan
(assuming I can get that far in my coach) in the hope that
I can find someone to help me get my dash A/C to work for
the homeward trip!

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
~~ ~ D C "Mac" Macdonald ~ ~~
~ ~ Amateur Radio - K2GKK ~ ~
~ ~ USAF and FAA, Retired ~ ~
~ ~ ~ Oklahoma City, OK ~ ~ ~
~~ ~ ~ "The Money Pit" ~ ~ ~~
~ ~ ~ ~ TZE166V101966 ~ ~ ~ ~
~ ~ ~ '76 ex-Palm Beach ~ ~ ~
~ www.gmcmhphotos.com/okclb ~
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
______________
*[ ]~~~[][ ][|\
*--OO--[]---O-*


> To: gmclist@temp.gmcnet.org
> From: n9cv@comcast.net
> Date: Wed, 13 Mar 2013 00:42:26 -0500
> Subject: Re: [GMCnet] AC Gauges
>
> Here is the deal.
>
> A set gauges is a set of gauges they do not know the difference between the various refrigerants. If you are reading pressure it is all the same. Some gauge sets have marks on the scale for the various pressure ranges for the various refrigerants. Who cares? All you want to do is read pressures.
>
> The big difference in gauges for sale today is in the hose connection types. R12 (OEM GMC) uses a schrader type connection on both the high and low pressure sides. R-134 uses and different style and needs a different pair of hose connections.
>
> So what do you want to do? Well get a set of gauges and buy a pair of adapters to screw on the hoses to match the opposite type. My gauges were originally for R-12 with schrader type ends. With those ends I can connect to any R-12 and R-22 connections direct. I also can connect direct to a vacuum pump or a large container of Duracool, r-12, r-22 or r-134 with the 3rd hose.
>
> If I am doing a R-134 vehicle I have a pair of adapters that screw on the hose ends and now I can connect to the r-134 connections on a modern vehicle.
>
> So if you buying a set of gauges, just make sure you also get a set of adapters to match the other connection types and you will be OK.
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana

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Re: AC Gauges [message #201577 is a reply to message #201513] Wed, 13 March 2013 13:51 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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I just looked at that set and it looks like it has the R-12 schrader type hoses and includes two R-134 adapters to go on those hoses. Now all you will need in addition is a good vacuum pump and maybe an adapter for the 3rd (center) hose.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: AC Gauges [message #201581 is a reply to message #201577] Wed, 13 March 2013 14:28 Go to previous messageGo to next message
X   United States
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.

[Updated on: Mon, 23 December 2013 19:15]

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Re: AC Gauges [message #201583 is a reply to message #201581] Wed, 13 March 2013 14:33 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
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Rob, I use the cheap $15 HF vacuum pump for a different use. To drain my water system, I connect it to the drain on the hot water tank. It pulls enough vacuum to completely drain the entire water system. This method has worked for 3 hard winters in Northern Virgina, and whatever they call winter here in Mississippi.
Re-purpose and reuse. A mind is a terrible thing to waste, mine is gone.
Tom, MS II


2012 Phoenix Cruiser model 2552 KA4CSG
Re: [GMCnet] AC Gauges [message #201587 is a reply to message #201583] Wed, 13 March 2013 14:50 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Tom,

That's an interesting idea.

Regards,
Rob M.

-----Original Message-----
From: Thomas Phipps

Rob, I use the cheap $15 HF vacuum pump for a different use. To drain my water system, I connect it to the drain on the hot water
tank. It pulls enough vacuum to completely drain the entire water system. This method has worked for 3 hard winters in Northern
Virgina, and whatever they call winter here in Mississippi.
Re-purpose and reuse. A mind is a terrible thing to waste, mine is gone.
Tom

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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: AC Gauges [message #201769 is a reply to message #201464] Fri, 15 March 2013 23:01 Go to previous messageGo to next message
Luvn737s is currently offline  Luvn737s   United States
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DUMB QUESTION ALERT-

Does the roof air need recharging and if so are they 134a, generally?



Randy
1973 26' Painted Desert
Ahwatukee (Phoenix) AZ
Re: [GMCnet] AC Gauges [message #201773 is a reply to message #201769] Fri, 15 March 2013 23:10 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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No,

The roof air is a sealed unit and does not have fittings like the dash air. IIRC it uses R-22.

Regards,
Rob M.

-----Original Message-----
From Randy

Does the roof air need recharging and if so are they 134a, generally?

Randy

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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: [GMCnet] AC Gauges [message #201787 is a reply to message #201773] Sat, 16 March 2013 07:05 Go to previous messageGo to previous message
tphipps is currently offline  tphipps   United States
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And, according to posts on the GMCnet, opening and recharging the roof air is an iffy proposition.
Tom, MS II


2012 Phoenix Cruiser model 2552 KA4CSG
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