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76 Birch air conditioning - I'm going in

DS
dave silva
Sat, Jul 17, 2021 12:16 PM

This coach was restored in 2013 and then sat for seven years. I've been slowly recommissioning it.

The AC worked.  Now it doesn't.  Apparently a very slow leak.  It has no pressure but it holds vacuum.

It had been converted to R134.  I have a case of duracool.

So what do i need to know besides adding duracool and crossing fingers ?

--
Dave & Ellen Silva
Hertford, NC

76  Birchaven, 1-ton and other stuff

Currently planning the Great american Road Trip Summer 2021

It's gonna take a lot of Adderall to get this thing right.

This coach was restored in 2013 and then sat for seven years. I've been slowly recommissioning it. The AC worked. Now it doesn't. Apparently a very slow leak. It has no pressure but it holds vacuum. It had been converted to R134. I have a case of duracool. So what do i need to know besides adding duracool and crossing fingers ? -- Dave & Ellen Silva Hertford, NC 76 Birchaven, 1-ton and other stuff Currently planning the Great american Road Trip Summer 2021 It's gonna take a lot of Adderall to get this thing right.
JH
James Hupy
Sat, Jul 17, 2021 1:48 PM

If you have R-134a, and it was professionally installed, they used an oil
specifically compatible with that refrigerant. It will NOT BE compatible
with either R-12 or Duracool type refrigerants.  The system must be pumped
down, the dessicant/dryer replaced, and thoroughly flushed of all that old
lubricant. If you have an OEM compressor, it should be drained and flushed,
and new lube filled. If you don't flush and replace the lube, be prepared
for a system full of sludge.
Jim Hupy
Salem, Oregon

On Sat, Jul 17, 2021, 5:17 AM dave silva admin@oldrv.net wrote:

This coach was restored in 2013 and then sat for seven years. I've been
slowly recommissioning it.

The AC worked.  Now it doesn't.  Apparently a very slow leak.  It has no
pressure but it holds vacuum.

It had been converted to R134.  I have a case of duracool.

So what do i need to know besides adding duracool and crossing fingers ?

--
Dave & Ellen Silva
Hertford, NC

76  Birchaven, 1-ton and other stuff

Currently planning the Great american Road Trip Summer 2021

It's gonna take a lot of Adderall to get this thing right.


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Unsubscribe or Change List Options:

If you have R-134a, and it was professionally installed, they used an oil specifically compatible with that refrigerant. It will NOT BE compatible with either R-12 or Duracool type refrigerants. The system must be pumped down, the dessicant/dryer replaced, and thoroughly flushed of all that old lubricant. If you have an OEM compressor, it should be drained and flushed, and new lube filled. If you don't flush and replace the lube, be prepared for a system full of sludge. Jim Hupy Salem, Oregon On Sat, Jul 17, 2021, 5:17 AM dave silva <admin@oldrv.net> wrote: > This coach was restored in 2013 and then sat for seven years. I've been > slowly recommissioning it. > > The AC worked. Now it doesn't. Apparently a very slow leak. It has no > pressure but it holds vacuum. > > It had been converted to R134. I have a case of duracool. > > So what do i need to know besides adding duracool and crossing fingers ? > > > -- > Dave & Ellen Silva > Hertford, NC > > 76 Birchaven, 1-ton and other stuff > > Currently planning the Great american Road Trip Summer 2021 > > It's gonna take a lot of Adderall to get this thing right. > > _______________________________________________ > GMCnet mailing list > Unsubscribe or Change List Options: >
ES
Emery Stora
Sat, Jul 17, 2021 2:05 PM

James
Duracool is compatible with the oil used with R12 and also compatible with the oil used with R134a.
If the system was properly converted for R134a then Duracool can be installed without changing anything.

Emery STORA
77 Kingsley
Frederick CO

On Jul 17, 2021, at 7:49 AM, James Hupy jamesh1296@gmail.com wrote:

If you have R-134a, and it was professionally installed, they used an oil
specifically compatible with that refrigerant. It will NOT BE compatible
with either R-12 or Duracool type refrigerants.  The system must be pumped
down, the dessicant/dryer replaced, and thoroughly flushed of all that old
lubricant. If you have an OEM compressor, it should be drained and flushed,
and new lube filled. If you don't flush and replace the lube, be prepared
for a system full of sludge.
Jim Hupy
Salem, Oregon

On Sat, Jul 17, 2021, 5:17 AM dave silva admin@oldrv.net wrote:

This coach was restored in 2013 and then sat for seven years. I've been
slowly recommissioning it.

The AC worked.  Now it doesn't.  Apparently a very slow leak.  It has no
pressure but it holds vacuum.

It had been converted to R134.  I have a case of duracool.

So what do i need to know besides adding duracool and crossing fingers ?

--
Dave & Ellen Silva
Hertford, NC

76  Birchaven, 1-ton and other stuff

Currently planning the Great american Road Trip Summer 2021

It's gonna take a lot of Adderall to get this thing right.


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GMCnet mailing list
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James Duracool is compatible with the oil used with R12 and also compatible with the oil used with R134a. If the system was properly converted for R134a then Duracool can be installed without changing anything. Emery STORA 77 Kingsley Frederick CO > On Jul 17, 2021, at 7:49 AM, James Hupy <jamesh1296@gmail.com> wrote: > > If you have R-134a, and it was professionally installed, they used an oil > specifically compatible with that refrigerant. It will NOT BE compatible > with either R-12 or Duracool type refrigerants. The system must be pumped > down, the dessicant/dryer replaced, and thoroughly flushed of all that old > lubricant. If you have an OEM compressor, it should be drained and flushed, > and new lube filled. If you don't flush and replace the lube, be prepared > for a system full of sludge. > Jim Hupy > Salem, Oregon > >> On Sat, Jul 17, 2021, 5:17 AM dave silva <admin@oldrv.net> wrote: >> >> This coach was restored in 2013 and then sat for seven years. I've been >> slowly recommissioning it. >> >> The AC worked. Now it doesn't. Apparently a very slow leak. It has no >> pressure but it holds vacuum. >> >> It had been converted to R134. I have a case of duracool. >> >> So what do i need to know besides adding duracool and crossing fingers ? >> >> >> -- >> Dave & Ellen Silva >> Hertford, NC >> >> 76 Birchaven, 1-ton and other stuff >> >> Currently planning the Great american Road Trip Summer 2021 >> >> It's gonna take a lot of Adderall to get this thing right. >> >> _______________________________________________ >> GMCnet mailing list >> Unsubscribe or Change List Options: >> > _______________________________________________ > GMCnet mailing list > Unsubscribe or Change List Options:
JH
James Hupy
Sat, Jul 17, 2021 2:56 PM

Au Contraire' Emery.
R-12 lube is mineral based.
R-134a lube is not mineral oil, but is something called PAG which is a
synthetic lube. According to the Rules and Laws, R-134a and R-12 cannot be
mixed, that goes for HC-12a  or "duracool" as well. Emery, you can do as
you wish, but those are the facts as I learned them from GM Training
School. Still have the books. I went and looked them up. Just what I was
taught.
Jim Hupy
Salem, Oregon

On Sat, Jul 17, 2021, 7:05 AM Emery Stora via Gmclist <
gmclist@list.gmcnet.org> wrote:

James
Duracool is compatible with the oil used with R12 and also compatible with
the oil used with R134a.
If the system was properly converted for R134a then Duracool can be
installed without changing anything.

Emery STORA
77 Kingsley
Frederick CO

On Jul 17, 2021, at 7:49 AM, James Hupy jamesh1296@gmail.com wrote:

If you have R-134a, and it was professionally installed, they used an

oil

specifically compatible with that refrigerant. It will NOT BE compatible
with either R-12 or Duracool type refrigerants.  The system must be

pumped

down, the dessicant/dryer replaced, and thoroughly flushed of all that

old

lubricant. If you have an OEM compressor, it should be drained and

flushed,

and new lube filled. If you don't flush and replace the lube, be prepared
for a system full of sludge.
Jim Hupy
Salem, Oregon

On Sat, Jul 17, 2021, 5:17 AM dave silva admin@oldrv.net wrote:

This coach was restored in 2013 and then sat for seven years. I've been
slowly recommissioning it.

The AC worked.  Now it doesn't.  Apparently a very slow leak.  It has no
pressure but it holds vacuum.

It had been converted to R134.  I have a case of duracool.

So what do i need to know besides adding duracool and crossing fingers ?

--
Dave & Ellen Silva
Hertford, NC

76  Birchaven, 1-ton and other stuff

Currently planning the Great american Road Trip Summer 2021

It's gonna take a lot of Adderall to get this thing right.


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GMCnet mailing list
Unsubscribe or Change List Options:


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Au Contraire' Emery. R-12 lube is mineral based. R-134a lube is not mineral oil, but is something called PAG which is a synthetic lube. According to the Rules and Laws, R-134a and R-12 cannot be mixed, that goes for HC-12a or "duracool" as well. Emery, you can do as you wish, but those are the facts as I learned them from GM Training School. Still have the books. I went and looked them up. Just what I was taught. Jim Hupy Salem, Oregon On Sat, Jul 17, 2021, 7:05 AM Emery Stora via Gmclist < gmclist@list.gmcnet.org> wrote: > James > Duracool is compatible with the oil used with R12 and also compatible with > the oil used with R134a. > If the system was properly converted for R134a then Duracool can be > installed without changing anything. > > Emery STORA > 77 Kingsley > Frederick CO > > > On Jul 17, 2021, at 7:49 AM, James Hupy <jamesh1296@gmail.com> wrote: > > > > If you have R-134a, and it was professionally installed, they used an > oil > > specifically compatible with that refrigerant. It will NOT BE compatible > > with either R-12 or Duracool type refrigerants. The system must be > pumped > > down, the dessicant/dryer replaced, and thoroughly flushed of all that > old > > lubricant. If you have an OEM compressor, it should be drained and > flushed, > > and new lube filled. If you don't flush and replace the lube, be prepared > > for a system full of sludge. > > Jim Hupy > > Salem, Oregon > > > >> On Sat, Jul 17, 2021, 5:17 AM dave silva <admin@oldrv.net> wrote: > >> > >> This coach was restored in 2013 and then sat for seven years. I've been > >> slowly recommissioning it. > >> > >> The AC worked. Now it doesn't. Apparently a very slow leak. It has no > >> pressure but it holds vacuum. > >> > >> It had been converted to R134. I have a case of duracool. > >> > >> So what do i need to know besides adding duracool and crossing fingers ? > >> > >> > >> -- > >> Dave & Ellen Silva > >> Hertford, NC > >> > >> 76 Birchaven, 1-ton and other stuff > >> > >> Currently planning the Great american Road Trip Summer 2021 > >> > >> It's gonna take a lot of Adderall to get this thing right. > >> > >> _______________________________________________ > >> GMCnet mailing list > >> Unsubscribe or Change List Options: > >> > > _______________________________________________ > > GMCnet mailing list > > Unsubscribe or Change List Options: > _______________________________________________ > GMCnet mailing list > Unsubscribe or Change List Options: >
JH
James Hupy
Sat, Jul 17, 2021 3:08 PM

The one oil that both refrigerants ARE compatible with is called POE,
which is Polyol Ester Oil.
If, when the R-134a was introduced into Dave's GMC that oil was used, then
HC-12a can be added to replace R-134a with no ill effects. Just Sayin, that
is a big IF.
Jim Hupy
Salem, Oregon

On Sat, Jul 17, 2021, 7:56 AM James Hupy jamesh1296@gmail.com wrote:

Au Contraire' Emery.
R-12 lube is mineral based.
R-134a lube is not mineral oil, but is something called PAG which is a
synthetic lube. According to the Rules and Laws, R-134a and R-12 cannot be
mixed, that goes for HC-12a  or "duracool" as well. Emery, you can do as
you wish, but those are the facts as I learned them from GM Training
School. Still have the books. I went and looked them up. Just what I was
taught.
Jim Hupy
Salem, Oregon

On Sat, Jul 17, 2021, 7:05 AM Emery Stora via Gmclist <
gmclist@list.gmcnet.org> wrote:

James
Duracool is compatible with the oil used with R12 and also compatible
with the oil used with R134a.
If the system was properly converted for R134a then Duracool can be
installed without changing anything.

Emery STORA
77 Kingsley
Frederick CO

On Jul 17, 2021, at 7:49 AM, James Hupy jamesh1296@gmail.com wrote:

If you have R-134a, and it was professionally installed, they used an

oil

specifically compatible with that refrigerant. It will NOT BE compatible
with either R-12 or Duracool type refrigerants.  The system must be

pumped

down, the dessicant/dryer replaced, and thoroughly flushed of all that

old

lubricant. If you have an OEM compressor, it should be drained and

flushed,

and new lube filled. If you don't flush and replace the lube, be

prepared

for a system full of sludge.
Jim Hupy
Salem, Oregon

On Sat, Jul 17, 2021, 5:17 AM dave silva admin@oldrv.net wrote:

This coach was restored in 2013 and then sat for seven years. I've been
slowly recommissioning it.

The AC worked.  Now it doesn't.  Apparently a very slow leak.  It has

no

pressure but it holds vacuum.

It had been converted to R134.  I have a case of duracool.

So what do i need to know besides adding duracool and crossing fingers

?

--
Dave & Ellen Silva
Hertford, NC

76  Birchaven, 1-ton and other stuff

Currently planning the Great american Road Trip Summer 2021

It's gonna take a lot of Adderall to get this thing right.


GMCnet mailing list
Unsubscribe or Change List Options:


GMCnet mailing list
Unsubscribe or Change List Options:


GMCnet mailing list
Unsubscribe or Change List Options:

The one oil that both refrigerants ARE compatible with is called POE, which is Polyol Ester Oil. If, when the R-134a was introduced into Dave's GMC that oil was used, then HC-12a can be added to replace R-134a with no ill effects. Just Sayin, that is a big IF. Jim Hupy Salem, Oregon On Sat, Jul 17, 2021, 7:56 AM James Hupy <jamesh1296@gmail.com> wrote: > Au Contraire' Emery. > R-12 lube is mineral based. > R-134a lube is not mineral oil, but is something called PAG which is a > synthetic lube. According to the Rules and Laws, R-134a and R-12 cannot be > mixed, that goes for HC-12a or "duracool" as well. Emery, you can do as > you wish, but those are the facts as I learned them from GM Training > School. Still have the books. I went and looked them up. Just what I was > taught. > Jim Hupy > Salem, Oregon > > On Sat, Jul 17, 2021, 7:05 AM Emery Stora via Gmclist < > gmclist@list.gmcnet.org> wrote: > >> James >> Duracool is compatible with the oil used with R12 and also compatible >> with the oil used with R134a. >> If the system was properly converted for R134a then Duracool can be >> installed without changing anything. >> >> Emery STORA >> 77 Kingsley >> Frederick CO >> >> > On Jul 17, 2021, at 7:49 AM, James Hupy <jamesh1296@gmail.com> wrote: >> > >> > If you have R-134a, and it was professionally installed, they used an >> oil >> > specifically compatible with that refrigerant. It will NOT BE compatible >> > with either R-12 or Duracool type refrigerants. The system must be >> pumped >> > down, the dessicant/dryer replaced, and thoroughly flushed of all that >> old >> > lubricant. If you have an OEM compressor, it should be drained and >> flushed, >> > and new lube filled. If you don't flush and replace the lube, be >> prepared >> > for a system full of sludge. >> > Jim Hupy >> > Salem, Oregon >> > >> >> On Sat, Jul 17, 2021, 5:17 AM dave silva <admin@oldrv.net> wrote: >> >> >> >> This coach was restored in 2013 and then sat for seven years. I've been >> >> slowly recommissioning it. >> >> >> >> The AC worked. Now it doesn't. Apparently a very slow leak. It has >> no >> >> pressure but it holds vacuum. >> >> >> >> It had been converted to R134. I have a case of duracool. >> >> >> >> So what do i need to know besides adding duracool and crossing fingers >> ? >> >> >> >> >> >> -- >> >> Dave & Ellen Silva >> >> Hertford, NC >> >> >> >> 76 Birchaven, 1-ton and other stuff >> >> >> >> Currently planning the Great american Road Trip Summer 2021 >> >> >> >> It's gonna take a lot of Adderall to get this thing right. >> >> >> >> _______________________________________________ >> >> GMCnet mailing list >> >> Unsubscribe or Change List Options: >> >> >> > _______________________________________________ >> > GMCnet mailing list >> > Unsubscribe or Change List Options: >> _______________________________________________ >> GMCnet mailing list >> Unsubscribe or Change List Options: >> >
TG
tom geiger
Sat, Jul 17, 2021 11:11 PM

Kinda preparing to go thru this as well.  I have a 76 Eleganza so in the same boat.  Did the PO do the recirculation mod on the air box?

Tom Geiger
76 Eleganza II
KCMO

Kinda preparing to go thru this as well. I have a 76 Eleganza so in the same boat. Did the PO do the recirculation mod on the air box? -- Tom Geiger 76 Eleganza II KCMO
DS
dave silva
Sat, Jul 17, 2021 11:16 PM

tgeiger wrote on Sat, 17 July 2021 18:11

Kinda preparing to go thru this as well.  I have a 76 Eleganza so in the same boat.  Did the PO do the recirculation mod on the air box?

No idea.The work was done by the COOP. Not sure what standard options are and i haven't asked  Jim B. about the AC

What is the recirc mod and how can i tell ?

--
Dave & Ellen Silva
Hertford, NC

76  Birchaven, 1-ton and other stuff

Currently planning the Great american Road Trip Summer 2021

It's gonna take a lot of Adderall to get this thing right.

tgeiger wrote on Sat, 17 July 2021 18:11 > Kinda preparing to go thru this as well. I have a 76 Eleganza so in the same boat. Did the PO do the recirculation mod on the air box? No idea.The work was done by the COOP. Not sure what standard options are and i haven't asked Jim B. about the AC What is the recirc mod and how can i tell ? -- Dave & Ellen Silva Hertford, NC 76 Birchaven, 1-ton and other stuff Currently planning the Great american Road Trip Summer 2021 It's gonna take a lot of Adderall to get this thing right.
TM
Tom McManus
Sun, Jul 18, 2021 8:27 AM

Dave
I would recommend replacing all the seals on the system.

Tom McManus
1977 Royale

Chesapeake VA

Dave I would recommend replacing all the seals on the system. -- Tom McManus 1977 Royale Chesapeake VA
JR
Jon Roche
Sun, Jul 18, 2021 12:55 PM

Dave,

You are gambling with $40 worth of duracool.

You can pull a vacuum, make sure it holds that vacuum.    Your patience on how long to watch the needle
Drop varies on how
Much you care about $40 or having to add more later.    I dont have patience so usually I only hold a vacuum for maybe an hour at
Most,
Most times it is however long i go inside to get something to eat
Or drink.

Then pop on a can,  fire up engine.  Short out the “high” pressure switch plug so compressor kicks on and let it take that can add the others and
then start watching pressures.  Get someone to get the rpms up.

You will find your $40 charge will last forever.  Or eventually
Might need another $6.99 can someday.  I have seen some last and my friend Ed we put
A can in just before summer.  This time i think i might know where our leak might be. (Valve core).  So will find one and try that.

You could go through alot
Of work and guessing to search out leaks.  Chances are $40 worth of duracool will probably keep you cool as needed.

Jon Roche
75 palm beach
EBL EFI, manny headers, Micro Level, rebuilt most of coach now.
St. Cloud, MN
http://lqqkatjon.blogspot.com/

Dave, You are gambling with $40 worth of duracool. You can pull a vacuum, make sure it holds that vacuum. Your patience on how long to watch the needle Drop varies on how Much you care about $40 or having to add more later. I dont have patience so usually I only hold a vacuum for maybe an hour at Most, Most times it is however long i go inside to get something to eat Or drink. Then pop on a can, fire up engine. Short out the “high” pressure switch plug so compressor kicks on and let it take that can add the others and then start watching pressures. Get someone to get the rpms up. You will find your $40 charge will last forever. Or eventually Might need another $6.99 can someday. I have seen some last and my friend Ed we put A can in just before summer. This time i think i might know where our leak might be. (Valve core). So will find one and try that. You could go through alot Of work and guessing to search out leaks. Chances are $40 worth of duracool will probably keep you cool as needed. -- Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
DS
dave silva
Sun, Jul 18, 2021 1:35 PM

lqqkatjon wrote on Sun, 18 July 2021 07:55

Dave,

You are gambling with $40 worth of duracool.

Then pop on a can,  fire up engine.  Short out the “high” pressure switch plug so compressor kicks on and let it take that can add the others
and then start watching pressures.  Get someone to get the rpms up.

Thanks, that's the info i was looking for.

It actually held vacuum for a long time, like overnight.

--
Dave & Ellen Silva
Hertford, NC

76  Birchaven, 1-ton and other stuff

Currently planning the Great american Road Trip Summer 2021

It's gonna take a lot of Adderall to get this thing right.

lqqkatjon wrote on Sun, 18 July 2021 07:55 > Dave, > > You are gambling with $40 worth of duracool. > > Then pop on a can, fire up engine. Short out the “high” pressure switch plug so compressor kicks on and let it take that can add the others > and then start watching pressures. Get someone to get the rpms up. Thanks, that's the info i was looking for. It actually held vacuum for a long time, like overnight. -- Dave & Ellen Silva Hertford, NC 76 Birchaven, 1-ton and other stuff Currently planning the Great american Road Trip Summer 2021 It's gonna take a lot of Adderall to get this thing right.