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Replacing AC compressor - Couple questions [message #344408] Sat, 22 June 2019 08:03 Go to next message
Will Albers is currently offline  Will Albers   United States
Messages: 183
Registered: November 2017
Location: Detroit MI (Belleville)
Karma: 2
Senior Member
My stock compressor more or less seized, so i have a S6 replacement about to go in. Would you consider a flush mandatory when swapping compressors? My thought here is that there are decades of oils built up in the system that should be removed. Am i over thinking it?

Also, on http://gmcmotorhome.info/heat.html - It states:

Here are some bits of information that we learned at Osoyoos: (5/5/5)
1 AC technicians do not like to use 134, it is harmful to their health.
2 You do not need a vacuum pump to charge with Hydrocarbon refrigerants like DuraCool (Propane).
3 In fact they work better if you do not pull a vacuum.
4 Propane will mix with whatever you have in your system. There's nothing to change.
5 Recover the existing refrigerant (most of our systems are already empty).
6 Add 3 cans of DuraCool

I'm very curious about #3. The link no longer works. Does anyone know why it works better without pulling a vaccum?


1978 Palm Beach.
Detroit Michigan
Re: Replacing AC compressor - Couple questions [message #344409 is a reply to message #344408] Sat, 22 June 2019 08:31 Go to previous messageGo to next message
C Boyd is currently offline  C Boyd   United States
Messages: 2629
Registered: April 2006
Karma: 18
Senior Member
Sir: I am not a qualified anything. Anytime your AC system is open to the atmosphere it gets air and moisture in it. Vacuuming the system removes the moisture which will freeze inside the lines and stop up the system.
As for 134-A being dangerous, I don't doubt that at all. However I use a PROAIR HFA (albuterol sulfate) inhalation aerosol for my COPD. The propellant used is 134-A.




Will Albers wrote on Sat, 22 June 2019 09:03
My stock compressor more or less seized, so i have a S6 replacement about to go in. Would you consider a flush mandatory when swapping compressors? My thought here is that there are decades of oils built up in the system that should be removed. Am i over thinking it?

Also, on http://gmcmotorhome.info/heat.html - It states:

Here are some bits of information that we learned at Osoyoos: (5/5/5)
1 AC technicians do not like to use 134, it is harmful to their health.
2 You do not need a vacuum pump to charge with Hydrocarbon refrigerants like DuraCool (Propane).
3 In fact they work better if you do not pull a vacuum.
4 Propane will mix with whatever you have in your system. There's nothing to change.
5 Recover the existing refrigerant (most of our systems are already empty).
6 Add 3 cans of DuraCool

I'm very curious about #3. The link no longer works. Does anyone know why it works better without pulling a vaccum?


C. Boyd
76 Crestmont
East Tennessee
Re: [GMCnet] Replacing AC compressor - Couple questions [message #344410 is a reply to message #344408] Sat, 22 June 2019 10:16 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member
I was at Osoyoos Canada in 05. The planked salmon was fantastic!

I did a few installs of Duracool while there.

I agree with your statements
except numbers 2 and 3.

There are times when you do need to evacuate the system. If is has been open to the atmosphere so as to allow air and moisture in it should be evacuated. If the system is still sealed and has pressure then most people look over their shoulder to make sure the air conditioning police are not looking and bleed off the old refrigerant and install Duracool. You can not recover what is in there unless you have the machine to do it.

As to working better if you don’t pull a vacuum that is exactly the opposite of what I believe. It will usually work but if you leave some of the old refrigerant in you will have a mixture of refrigerants and that will not work as efficiently as straight Duracool. So it is best to evacuate if you have a vacuum pump. If there is ang chance that there is water moisture in the system that should definitely be vacuumed out.

How can there be decades of oils built up in the system if you haven’t added any oil? The oil in there doesn’t degrade.

The only reason to flush is if you have a mixture of oils in the system. They can eventually interact and form “sludge” in the system. The last time I replaced a compressor, the new compressor contained oil suitable for R-134a and that would be mixed with the mineral oil used for R-12. So, I drained the oil from the new compressor and measured how much it contained. I then flushed out the compressor with naphtha or mineral spirits a couple of times and pressure blew it out with dry air. I then installed the same volume I drained out with mineral oil for air conditioners from NAPA.

By the way, it was discovered years back that R134a exposure can cause testicular cancer. That would scare any man!

Emery Stora
77 Kingsley
Frederick CO

> On Jun 22, 2019, at 7:03 AM, Will Albers via Gmclist wrote:
>
> My stock compressor more or less seized, so i have a S6 replacement about to go in. Would you consider a flush mandatory when swapping compressors? My
> thought here is that there are decades of oils built up in the system that should be removed. Am i over thinking it?
>
> Also, on http://gmcmotorhome.info/heat.html - It states:
>
> Here are some bits of information that we learned at Osoyoos: (5/5/5)
> 1 AC technicians do not like to use 134, it is harmful to their health.
> 2 You do not need a vacuum pump to charge with Hydrocarbon refrigerants like DuraCool (Propane).
> 3 In fact they work better if you do not pull a vacuum.
> 4 Propane will mix with whatever you have in your system. There's nothing to change.
> 5 Recover the existing refrigerant (most of our systems are already empty).
> 6 Add 3 cans of DuraCool
>
> I'm very curious about #3. The link no longer works. Does anyone know why it works better without pulling a vaccum?
> --
> 1978 Palm Beach.
> Detroit Michigan
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


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Re: [GMCnet] Replacing AC compressor - Couple questions [message #344414 is a reply to message #344410] Sat, 22 June 2019 11:33 Go to previous messageGo to next message
Jp Benson is currently offline  Jp Benson   United States
Messages: 649
Registered: October 2011
Location: Fla
Karma: 2
Senior Member
If the old compressor seized then I would definitely flush the system. Remove the old compressor and the filter/dryer. Flush the pipes etc. Install a new filter/dryer, install the replacement compressor, pull a vacuum and see if it holds overnight. If the vacuum holds then add duracool. Otherwise find the leak(s). As Emery mentioned make sure you have the correct oil charge.

JP
Re: [GMCnet] Replacing AC compressor - Couple questions [message #344435 is a reply to message #344410] Sat, 22 June 2019 21:56 Go to previous messageGo to next message
Dolph Santorine is currently offline  Dolph Santorine   United States
Messages: 1236
Registered: April 2011
Location: Wheeling, WV
Karma: -41
Senior Member
I’m with you Emery. I vacuum them down before charging.

I do a nitrogen purge and check for leaks at 300 psi because nitrogen is cheap, and it’s easier to identify bubbles than it is to look for fluorescent dye.

I don’t know about threats to my manhood from refrigerant, but I do know that inoperative AC poses significant threats from my wife.

Dolph Santorine

DE AD0LF

Wheeling, West Virginia

1977 ex-Palm Beach TZE167V100820
Howell EFI/EBL , Reaction Arms, Manny Transmission


> On Jun 22, 2019, at 11:16 AM, Emery Stora via Gmclist wrote:
>
> I was at Osoyoos Canada in 05. The planked salmon was fantastic!
>
> I did a few installs of Duracool while there.
>
> I agree with your statements
> except numbers 2 and 3.
>
> There are times when you do need to evacuate the system. If is has been open to the atmosphere so as to allow air and moisture in it should be evacuated. If the system is still sealed and has pressure then most people look over their shoulder to make sure the air conditioning police are not looking and bleed off the old refrigerant and install Duracool. You can not recover what is in there unless you have the machine to do it.
>
> As to working better if you don’t pull a vacuum that is exactly the opposite of what I believe. It will usually work but if you leave some of the old refrigerant in you will have a mixture of refrigerants and that will not work as efficiently as straight Duracool. So it is best to evacuate if you have a vacuum pump. If there is ang chance that there is water moisture in the system that should definitely be vacuumed out.
>
> How can there be decades of oils built up in the system if you haven’t added any oil? The oil in there doesn’t degrade.
>
> The only reason to flush is if you have a mixture of oils in the system. They can eventually interact and form “sludge” in the system. The last time I replaced a compressor, the new compressor contained oil suitable for R-134a and that would be mixed with the mineral oil used for R-12. So, I drained the oil from the new compressor and measured how much it contained. I then flushed out the compressor with naphtha or mineral spirits a couple of times and pressure blew it out with dry air. I then installed the same volume I drained out with mineral oil for air conditioners from NAPA.
>
> By the way, it was discovered years back that R134a exposure can cause testicular cancer. That would scare any man!
>
> Emery Stora
> 77 Kingsley
> Frederick CO
>
>> On Jun 22, 2019, at 7:03 AM, Will Albers via Gmclist wrote:
>>
>> My stock compressor more or less seized, so i have a S6 replacement about to go in. Would you consider a flush mandatory when swapping compressors? My
>> thought here is that there are decades of oils built up in the system that should be removed. Am i over thinking it?
>>
>> Also, on http://gmcmotorhome.info/heat.html - It states:
>>
>> Here are some bits of information that we learned at Osoyoos: (5/5/5)
>> 1 AC technicians do not like to use 134, it is harmful to their health.
>> 2 You do not need a vacuum pump to charge with Hydrocarbon refrigerants like DuraCool (Propane).
>> 3 In fact they work better if you do not pull a vacuum.
>> 4 Propane will mix with whatever you have in your system. There's nothing to change.
>> 5 Recover the existing refrigerant (most of our systems are already empty).
>> 6 Add 3 cans of DuraCool
>>
>> I'm very curious about #3. The link no longer works. Does anyone know why it works better without pulling a vaccum?
>> --
>> 1978 Palm Beach.
>> Detroit Michigan
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


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Re: [GMCnet] Replacing AC compressor - Couple questions [message #344438 is a reply to message #344410] Sun, 23 June 2019 05:10 Go to previous messageGo to next message
Will Albers is currently offline  Will Albers   United States
Messages: 183
Registered: November 2017
Location: Detroit MI (Belleville)
Karma: 2
Senior Member
Emory, answering your question on why i believe there is excess oil...

All of those quick over the counter a/c charge cans contain oil correct? I
believe its oil, coolant, and dye. I know my system had a minor leak, so i
wonder how many POs used the cheapest recharge can from kmart, only for the
refridgerant to leak, and leave the oils/dye at low points.

Again, i could be overthinking this.

Will

On Sat, Jun 22, 2019, 11:17 AM Emery Stora via Gmclist <
gmclist@list.gmcnet.org> wrote:

> I was at Osoyoos Canada in 05. The planked salmon was fantastic!
>
> I did a few installs of Duracool while there.
>
> I agree with your statements
> except numbers 2 and 3.
>
> There are times when you do need to evacuate the system. If is has been
> open to the atmosphere so as to allow air and moisture in it should be
> evacuated. If the system is still sealed and has pressure then most people
> look over their shoulder to make sure the air conditioning police are not
> looking and bleed off the old refrigerant and install Duracool. You can not
> recover what is in there unless you have the machine to do it.
>
> As to working better if you don’t pull a vacuum that is exactly the
> opposite of what I believe. It will usually work but if you leave some of
> the old refrigerant in you will have a mixture of refrigerants and that
> will not work as efficiently as straight Duracool. So it is best to
> evacuate if you have a vacuum pump. If there is ang chance that there is
> water moisture in the system that should definitely be vacuumed out.
>
> How can there be decades of oils built up in the system if you haven’t
> added any oil? The oil in there doesn’t degrade.
>
> The only reason to flush is if you have a mixture of oils in the system.
> They can eventually interact and form “sludge” in the system. The last time
> I replaced a compressor, the new compressor contained oil suitable for
> R-134a and that would be mixed with the mineral oil used for R-12. So, I
> drained the oil from the new compressor and measured how much it contained.
> I then flushed out the compressor with naphtha or mineral spirits a couple
> of times and pressure blew it out with dry air. I then installed the same
> volume I drained out with mineral oil for air conditioners from NAPA.
>
> By the way, it was discovered years back that R134a exposure can cause
> testicular cancer. That would scare any man!
>
> Emery Stora
> 77 Kingsley
> Frederick CO
>
>> On Jun 22, 2019, at 7:03 AM, Will Albers via Gmclist gmclist@list.gmcnet.org> wrote:
>>
>> My stock compressor more or less seized, so i have a S6 replacement
> about to go in. Would you consider a flush mandatory when swapping
> compressors? My
>> thought here is that there are decades of oils built up in the system
> that should be removed. Am i over thinking it?
>>
>> Also, on http://gmcmotorhome.info/heat.html - It states:
>>
>> Here are some bits of information that we learned at Osoyoos: (5/5/5)
>> 1 AC technicians do not like to use 134, it is harmful to their health.
>> 2 You do not need a vacuum pump to charge with Hydrocarbon refrigerants
> like DuraCool (Propane).
>> 3 In fact they work better if you do not pull a vacuum.
>> 4 Propane will mix with whatever you have in your system. There's
> nothing to change.
>> 5 Recover the existing refrigerant (most of our systems are already
> empty).
>> 6 Add 3 cans of DuraCool
>>
>> I'm very curious about #3. The link no longer works. Does anyone know
> why it works better without pulling a vaccum?
>> --
>> 1978 Palm Beach.
>> Detroit Michigan
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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1978 Palm Beach.
Detroit Michigan
Re: [GMCnet] Replacing AC compressor - Couple questions [message #344440 is a reply to message #344438] Sun, 23 June 2019 06:48 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member
No, most do not contain oils and dye. You have to pay more for those than for straight refrigerant.

If you have a leak the oil will usually also leak out.

If you suspect that you have excess oil they you should drain the condenser and evaporator and compressor and flush out those components and the hoses. Then replace the drier/accumulator. The GMC maintenance manual has a chart telling how much oil to add for each component. Then evacuate and check for leaks, then recharge.

Emery Stora

> On Jun 23, 2019, at 4:10 AM, Will via Gmclist wrote:
>
> Emory, answering your question on why i believe there is excess oil...
>
> All of those quick over the counter a/c charge cans contain oil correct? I
> believe its oil, coolant, and dye. I know my system had a minor leak, so i
> wonder how many POs used the cheapest recharge can from kmart, only for the
> refridgerant to leak, and leave the oils/dye at low points.
>
> Again, i could be overthinking this.
>
> Will
>
> On Sat, Jun 22, 2019, 11:17 AM Emery Stora via Gmclist gmclist@list.gmcnet.org> wrote:
>
>> I was at Osoyoos Canada in 05. The planked salmon was fantastic!
>>
>> I did a few installs of Duracool while there.
>>
>> I agree with your statements
>> except numbers 2 and 3.
>>
>> There are times when you do need to evacuate the system. If is has been
>> open to the atmosphere so as to allow air and moisture in it should be
>> evacuated. If the system is still sealed and has pressure then most people
>> look over their shoulder to make sure the air conditioning police are not
>> looking and bleed off the old refrigerant and install Duracool. You can not
>> recover what is in there unless you have the machine to do it.
>>
>> As to working better if you don’t pull a vacuum that is exactly the
>> opposite of what I believe. It will usually work but if you leave some of
>> the old refrigerant in you will have a mixture of refrigerants and that
>> will not work as efficiently as straight Duracool. So it is best to
>> evacuate if you have a vacuum pump. If there is ang chance that there is
>> water moisture in the system that should definitely be vacuumed out.
>>
>> How can there be decades of oils built up in the system if you haven’t
>> added any oil? The oil in there doesn’t degrade.
>>
>> The only reason to flush is if you have a mixture of oils in the system.
>> They can eventually interact and form “sludge” in the system. The last time
>> I replaced a compressor, the new compressor contained oil suitable for
>> R-134a and that would be mixed with the mineral oil used for R-12. So, I
>> drained the oil from the new compressor and measured how much it contained.
>> I then flushed out the compressor with naphtha or mineral spirits a couple
>> of times and pressure blew it out with dry air. I then installed the same
>> volume I drained out with mineral oil for air conditioners from NAPA.
>>
>> By the way, it was discovered years back that R134a exposure can cause
>> testicular cancer. That would scare any man!
>>
>> Emery Stora
>> 77 Kingsley
>> Frederick CO
>>
>>> On Jun 22, 2019, at 7:03 AM, Will Albers via Gmclist > gmclist@list.gmcnet.org> wrote:
>>>
>>> My stock compressor more or less seized, so i have a S6 replacement
>> about to go in. Would you consider a flush mandatory when swapping
>> compressors? My
>>> thought here is that there are decades of oils built up in the system
>> that should be removed. Am i over thinking it?
>>>
>>> Also, on http://gmcmotorhome.info/heat.html - It states:
>>>
>>> Here are some bits of information that we learned at Osoyoos: (5/5/5)
>>> 1 AC technicians do not like to use 134, it is harmful to their health.
>>> 2 You do not need a vacuum pump to charge with Hydrocarbon refrigerants
>> like DuraCool (Propane).
>>> 3 In fact they work better if you do not pull a vacuum.
>>> 4 Propane will mix with whatever you have in your system. There's
>> nothing to change.
>>> 5 Recover the existing refrigerant (most of our systems are already
>> empty).
>>> 6 Add 3 cans of DuraCool
>>>
>>> I'm very curious about #3. The link no longer works. Does anyone know
>> why it works better without pulling a vaccum?
>>> --
>>> 1978 Palm Beach.
>>> Detroit Michigan
>>>
>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


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Re: Replacing AC compressor - Couple questions [message #344479 is a reply to message #344408] Mon, 24 June 2019 07:47 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
Senior Member
If yopu are a cheapskate (guilty) and if you have the means, pull a vacuum overnight on the drier, and heat it with a heat lamp. This will remove the moisture trapped in it.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: [GMCnet] Replacing AC compressor - Couple questions [message #344485 is a reply to message #344479] Mon, 24 June 2019 09:29 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member
HOWEVER it is both a filter and a drier. You can get the moisture out but not any solids or particles. You could also flush the old oil from your engine oil filter and use it over but would you?

The savings you might gain with not replacing the air conditioner filter/drier would quickly disappear if you later have to replace it and recharge the system.

Emery Stora
7 Kingsley
Frederick CO

> On Jun 24, 2019, at 6:47 AM, Johnny Bridges via Gmclist wrote:
>
> If yopu are a cheapskate (guilty) and if you have the means, pull a vacuum overnight on the drier, and heat it with a heat lamp. This will remove the
> moisture trapped in it.
>
> --johnny
> --
> Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> I forgive them all, save those who hurt the dogs. They must answer to me in hell
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


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Re: [GMCnet] Replacing AC compressor - Couple questions [message #344486 is a reply to message #344485] Mon, 24 June 2019 09:38 Go to previous message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
My a/c tech and I tend to fight about the drier as I like to save $ on my
own coach, but experience dictate it it is not worth the $30 to gamble.

On Mon, Jun 24, 2019 at 7:30 AM Emery Stora via Gmclist <
gmclist@list.gmcnet.org> wrote:

> HOWEVER it is both a filter and a drier. You can get the moisture out but
> not any solids or particles. You could also flush the old oil from your
> engine oil filter and use it over but would you?
>
> The savings you might gain with not replacing the air conditioner
> filter/drier would quickly disappear if you later have to replace it and
> recharge the system.
>
> Emery Stora
> 7 Kingsley
> Frederick CO
>
>> On Jun 24, 2019, at 6:47 AM, Johnny Bridges via Gmclist gmclist@list.gmcnet.org> wrote:
>>
>> If yopu are a cheapskate (guilty) and if you have the means, pull a
> vacuum overnight on the drier, and heat it with a heat lamp. This will
> remove the
>> moisture trapped in it.
>>
>> --johnny
>> --
>> Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
>> Braselton, Ga.
>> I forgive them all, save those who hurt the dogs. They must answer to
> me in hell
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>


--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
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