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[GMCnet] Duracool installation pressures [message #174890] Thu, 28 June 2012 10:20 Go to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
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Senior Member
I think that some clarification is necessary regarding the low side pressure of Duracool.

Many have been quoting my statement that a pressure of 20 psi at 1500 RPM is the correct target for installation of Duracool.

HOWEVER, they do not give the whole story. When I first suggested this pressure on the GMCnet back in 2002 I had also said that this depends on the humidity where you use the GMC. I said that in high humidity conditions you might have to put in more Duracool in order to prevent freezing up of your evaporator coil. The next year I reported that on a trip to Florida I experienced this problem as there was very high humidity. I added a little more Duracool and the problem went away. This gave me a pressure of about 25 psi.

However, when I returned to NM and when I traveled to Arizona I found that I could get colder air conditioning if I went back to 20 psi. I could do this is because of the low humidity in those states.

I have also stated that the 20 psi target was with ambient temperatures of perhaps 90 and less. If the outside temperature is higher the pressure in the system will be higher so it might be necessary to add Duracool until the pressure was at 25 or so psi. You are not actually using any more Duracool but the measurement of the pressure in the system will be higher due to the higher temperatures. So, if you install it at, say 90 deg, to a 20 psi level and then later check the pressure when it is 100 or more you will find that there is indeed higher pressures in the system. So, if you are installing it at 100 deg and only put in 20 psi then you could possibly be undercharged at lower ambient temperatures.

If you have freezing of the evaporator you will know it. The humid air will cause ice to form on the fins in your heater box evaporator coil. When enough ice forms it will completely block the air flow through the coil. When this happened to me I thought that my blower motor had failed. To thaw the coils you can turn off the air conditioner but keep the fan on high. This will soon melt the ice and you will again get air flow through the air conditioning outlets. However, it will freeze up again after a while when you turn the air conditioner on again.

Emery Stora


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Re: [GMCnet] Duracool installation pressures [message #174891 is a reply to message #174890] Thu, 28 June 2012 10:24 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member
Some additional information:

If you use 3 six ounce cans of Duracool you will be very close to the proper charge. I have found that with the low humidity in NM I actually use a little less. Once you have the three cans in you can check your pressure and decide if you want to bleed off a little.

Emery Stora

On Jun 28, 2012, at 9:20 AM, Emery Stora wrote:

> I think that some clarification is necessary regarding the low side pressure of Duracool.
>
> Many have been quoting my statement that a pressure of 20 psi at 1500 RPM is the correct target for installation of Duracool.
>
> HOWEVER, they do not give the whole story. When I first suggested this pressure on the GMCnet back in 2002 I had also said that this depends on the humidity where you use the GMC. I said that in high humidity conditions you might have to put in more Duracool in order to prevent freezing up of your evaporator coil. The next year I reported that on a trip to Florida I experienced this problem as there was very high humidity. I added a little more Duracool and the problem went away. This gave me a pressure of about 25 psi.
>
> However, when I returned to NM and when I traveled to Arizona I found that I could get colder air conditioning if I went back to 20 psi. I could do this is because of the low humidity in those states.
>
> I have also stated that the 20 psi target was with ambient temperatures of perhaps 90 and less. If the outside temperature is higher the pressure in the system will be higher so it might be necessary to add Duracool until the pressure was at 25 or so psi. You are not actually using any more Duracool but the measurement of the pressure in the system will be higher due to the higher temperatures. So, if you install it at, say 90 deg, to a 20 psi level and then later check the pressure when it is 100 or more you will find that there is indeed higher pressures in the system. So, if you are installing it at 100 deg and only put in 20 psi then you could possibly be undercharged at lower ambient temperatures.
>
> If you have freezing of the evaporator you will know it. The humid air will cause ice to form on the fins in your heater box evaporator coil. When enough ice forms it will completely block the air flow through the coil. When this happened to me I thought that my blower motor had failed. To thaw the coils you can turn off the air conditioner but keep the fan on high. This will soon melt the ice and you will again get air flow through the air conditioning outlets. However, it will freeze up again after a while when you turn the air conditioner on again.
>
> Emery Stora
>
>

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Re: [GMCnet] Duracool installation pressures [message #174894 is a reply to message #174891] Thu, 28 June 2012 10:47 Go to previous messageGo to next message
Ray Erspamer is currently offline  Ray Erspamer   United States
Messages: 1707
Registered: May 2007
Location: Milwaukee Wisconsin
Karma: -3
Senior Member
Emery, I have great cooling with the Duracool but I get an occasional belt
squeal which seems like compressor lock up......maybe once every 20 to 30
minutes.....could I be over-charged ??? I need to recheck the pressure but
when I charged I followed the 20PSI at 1500 RPM

Ray


Ray & Lisa
78 Royale "Great Lakes Eagle"
Center Kitchen TZE368V101144
Wauwatosa, Wisconsin 53226
Email: 78GMC-Royale@att.net
414-745-3188
Web Site: http://ray-lisa.page.tl/




________________________________
From: Emery Stora <emerystora@mac.com>
To: gmclist@temp.gmcnet.org
Sent: Thu, June 28, 2012 10:24:45 AM
Subject: Re: [GMCnet] Duracool installation pressures

Some additional information:

If you use 3 six ounce cans of Duracool you will be very close to the proper
charge. I have found that with the low humidity in NM I actually use a little
less. Once you have the three cans in you can check your pressure and decide if
you want to bleed off a little.

Emery Stora

On Jun 28, 2012, at 9:20 AM, Emery Stora wrote:

> I think that some clarification is necessary regarding the low side pressure of
>Duracool.
>
> Many have been quoting my statement that a pressure of 20 psi at 1500 RPM is
>the correct target for installation of Duracool.
>
> HOWEVER, they do not give the whole story. When I first suggested this
>pressure on the GMCnet back in 2002 I had also said that this depends on the
>humidity where you use the GMC. I said that in high humidity conditions you
>might have to put in more Duracool in order to prevent freezing up of your
>evaporator coil. The next year I reported that on a trip to Florida I
>experienced this problem as there was very high humidity. I added a little more
>Duracool and the problem went away. This gave me a pressure of about 25 psi.
>
> However, when I returned to NM and when I traveled to Arizona I found that I
>could get colder air conditioning if I went back to 20 psi. I could do this is
>because of the low humidity in those states.
>
> I have also stated that the 20 psi target was with ambient temperatures of
>perhaps 90 and less. If the outside temperature is higher the pressure in the
>system will be higher so it might be necessary to add Duracool until the
>pressure was at 25 or so psi. You are not actually using any more Duracool but
>the measurement of the pressure in the system will be higher due to the higher
>temperatures. So, if you install it at, say 90 deg, to a 20 psi level and then
>later check the pressure when it is 100 or more you will find that there is
>indeed higher pressures in the system. So, if you are installing it at 100 deg
>and only put in 20 psi then you could possibly be undercharged at lower ambient
>temperatures.
>
> If you have freezing of the evaporator you will know it. The humid air will
>cause ice to form on the fins in your heater box evaporator coil. When enough
>ice forms it will completely block the air flow through the coil. When this
>happened to me I thought that my blower motor had failed. To thaw the coils you
>can turn off the air conditioner but keep the fan on high. This will soon melt
>the ice and you will again get air flow through the air conditioning outlets.
>However, it will freeze up again after a while when you turn the air conditioner
>on again.
>
> Emery Stora
>
>

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Ray Erspamer 78 GMC Royale Center Kitchen 403, 3.70 Final Drive Holley Sniper Quadrajet EFI System, Holley Hyperspark Ignition System 414-484-9431
Re: [GMCnet] Duracool installation pressures [message #174897 is a reply to message #174891] Thu, 28 June 2012 10:56 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
Messages: 2126
Registered: July 2004
Location: Minden nevada
Karma: 6
Senior Member
[quote title=emerystora wrote on Thu, 28 June 2012 08:24]Some additional information:

If you use 3 six ounce cans of Duracool you will be very close to the proper charge. I have found that with the low humidity in NM I actually use a little less. Once you have the three cans in you can check your pressure and decide if you want to bleed off a little.

Emery Stora

On Jun 28, 2012, at 9:20 AM, Emery Stora wrote:

> I think that some clarification is necessary regarding the low side pressure of Duracool.
>
> Many have been quoting my statement that a pressure of 20 psi at 1500 RPM is the correct target for installation of Duracool.
>
> HOWEVER, they do not give the whole story. When I first suggested this pressure on the GMCnet back in 2002 I had also said that this depends on the humidity where you use the GMC. I said that in high humidity conditions you might have to put in more Duracool in order to prevent freezing up of your evaporator coil. The next year I reported that on a trip to Florida I experienced this problem as there was very high humidity. I added a little more Duracool and the problem went away. This gave me a pressure of about 25 psi.
>
> However, when I returned to NM and when I traveled to Arizona I found that I could get colder air conditioning if I went back to 20 psi. I could do this is because of the low humidity in those states.
>
> I have also stated that the 20 psi target was with ambient temperatures of perhaps 90 and less. If the outside temperature is higher the pressure in the system will be higher so it might be necessary to add Duracool until the pressure was at 25 or so psi. You are not actually using any more Duracool but the measurement of the pressure in the system will be higher due to the higher temperatures. So, if you install it at, say 90 deg, to a 20 psi level and then later check the pressure when it is 100 or more you will find that there is indeed higher pressures in the system. So, if you are installing it at 100 deg and only put in 20 psi then you could possibly be undercharged at lower ambient temperatures.
>
> If you have freezing of the evaporator you will know it. The humid air will cause ice to form on the fins in your heater box evaporator coil. When enough ice forms it will completely block the air flow through the coil. When this happened to me I thought that my blower motor had failed. To thaw the coils you can turn off the air conditioner but keep the fan on high. This will soon melt the ice and you will again get air flow through the air conditioning outlets. However, it will freeze up again after a while when you turn the air conditioner on again.
>
> Emery Stora
>

Good that you posted that Emery . It should help some folks that are a tad short on there charge. Especially those with SOB's or Auto's that seam to run a little higher suction pressure then our GMC's.


Roy Keen Minden,NV 76 X Glenbrook
Re: [GMCnet] Duracool installation pressures [message #174899 is a reply to message #174890] Thu, 28 June 2012 11:04 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
Messages: 4508
Registered: April 2011
Karma: 39
Senior Member
Anybody running Duracool in a system with multiple evaporators? How much Duracool did it take to get the pressure right?
Re: [GMCnet] Duracool installation pressures [message #174901 is a reply to message #174899] Thu, 28 June 2012 11:08 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member
I have an additional 18,000 btu evaporator and 3 cans still work fine.

After going through the expansion valve the evaporator is essentially filled with vapor so it really doesn't take much, if any, more liquid Duracool.

Emery Stora

On Jun 28, 2012, at 10:04 AM, "A." <markbb1@netzero.com> wrote:

>
>
> Anybody running Duracool in a system with multiple evaporators? How much Duracool did it take to get the pressure right?
> --
> '73 23' CanyonLands
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Re: [GMCnet] Duracool installation pressures [message #174904 is a reply to message #174894] Thu, 28 June 2012 11:13 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member
Ray

I doubt that you have it overcharged. I would suspect your belt or the tension on the belt. The belt could be glazed from slipping. I suggest that you get a new belt (make sure it is 11 mm wide) and tension it properly. While the belt is off you should also clean the pulleys with some solvent to make sure there is no residual on them.

This might solve your problem.



Emery Stora

On Jun 28, 2012, at 9:47 AM, Ray Erspamer <78gmc-royale@att.net> wrote:

> Emery, I have great cooling with the Duracool but I get an occasional belt
> squeal which seems like compressor lock up......maybe once every 20 to 30
> minutes.....could I be over-charged ??? I need to recheck the pressure but
> when I charged I followed the 20PSI at 1500 RPM
>
> Ray
>
>
> Ray & Lisa
> 78 Royale "Great Lakes Eagle"
> Center Kitchen TZE368V101144
> Wauwatosa, Wisconsin 53226
> Email: 78GMC-Royale@att.net
> 414-745-3188
> Web Site: http://ray-lisa.page.tl/
>
>
>
>
> ________________________________
> From: Emery Stora <emerystora@mac.com>
> To: gmclist@temp.gmcnet.org
> Sent: Thu, June 28, 2012 10:24:45 AM
> Subject: Re: [GMCnet] Duracool installation pressures
>
> Some additional information:
>
> If you use 3 six ounce cans of Duracool you will be very close to the proper
> charge. I have found that with the low humidity in NM I actually use a little
> less. Once you have the three cans in you can check your pressure and decide if
> you want to bleed off a little.
>
> Emery Stora
>
> On Jun 28, 2012, at 9:20 AM, Emery Stora wrote:
>
>> I think that some clarification is necessary regarding the low side pressure of
>> Duracool.
>>
>> Many have been quoting my statement that a pressure of 20 psi at 1500 RPM is
>> the correct target for installation of Duracool.
>>
>> HOWEVER, they do not give the whole story. When I first suggested this
>> pressure on the GMCnet back in 2002 I had also said that this depends on the
>> humidity where you use the GMC. I said that in high humidity conditions you
>> might have to put in more Duracool in order to prevent freezing up of your
>> evaporator coil. The next year I reported that on a trip to Florida I
>> experienced this problem as there was very high humidity. I added a little more
>> Duracool and the problem went away. This gave me a pressure of about 25 psi.
>>
>> However, when I returned to NM and when I traveled to Arizona I found that I
>> could get colder air conditioning if I went back to 20 psi. I could do this is
>> because of the low humidity in those states.
>>
>> I have also stated that the 20 psi target was with ambient temperatures of
>> perhaps 90 and less. If the outside temperature is higher the pressure in the
>> system will be higher so it might be necessary to add Duracool until the
>> pressure was at 25 or so psi. You are not actually using any more Duracool but
>> the measurement of the pressure in the system will be higher due to the higher
>> temperatures. So, if you install it at, say 90 deg, to a 20 psi level and then
>> later check the pressure when it is 100 or more you will find that there is
>> indeed higher pressures in the system. So, if you are installing it at 100 deg
>> and only put in 20 psi then you could possibly be undercharged at lower ambient
>> temperatures.
>>
>> If you have freezing of the evaporator you will know it. The humid air will
>> cause ice to form on the fins in your heater box evaporator coil. When enough
>> ice forms it will completely block the air flow through the coil. When this
>> happened to me I thought that my blower motor had failed. To thaw the coils you
>> can turn off the air conditioner but keep the fan on high. This will soon melt
>> the ice and you will again get air flow through the air conditioning outlets.
>> However, it will freeze up again after a while when you turn the air conditioner
>> on again.
>>
>> Emery Stora
>>
>>
>
> _______________________________________________
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Re: [GMCnet] Duracool installation pressures [message #174909 is a reply to message #174904] Thu, 28 June 2012 11:28 Go to previous messageGo to next message
Ray Erspamer is currently offline  Ray Erspamer   United States
Messages: 1707
Registered: May 2007
Location: Milwaukee Wisconsin
Karma: -3
Senior Member
Will do, thanks Emery.

Ray


Ray & Lisa
78 Royale "Great Lakes Eagle"
Center Kitchen TZE368V101144
Wauwatosa, Wisconsin 53226
Email: 78GMC-Royale@att.net
414-745-3188
Web Site: http://ray-lisa.page.tl/




________________________________
From: Emery Stora <emerystora@mac.com>
To: "gmclist@temp.gmcnet.org" <gmclist@temp.gmcnet.org>
Sent: Thu, June 28, 2012 11:13:25 AM
Subject: Re: [GMCnet] Duracool installation pressures

Ray

I doubt that you have it overcharged. I would suspect your belt or the tension
on the belt. The belt could be glazed from slipping. I suggest that you get a
new belt (make sure it is 11 mm wide) and tension it properly. While the belt is
off you should also clean the pulleys with some solvent to make sure there is no
residual on them.


This might solve your problem.



Emery Stora

On Jun 28, 2012, at 9:47 AM, Ray Erspamer <78gmc-royale@att.net> wrote:

> Emery, I have great cooling with the Duracool but I get an occasional belt
> squeal which seems like compressor lock up......maybe once every 20 to 30
> minutes.....could I be over-charged ??? I need to recheck the pressure but
> when I charged I followed the 20PSI at 1500 RPM
>
> Ray
>
>
> Ray & Lisa
> 78 Royale "Great Lakes Eagle"
> Center Kitchen TZE368V101144
> Wauwatosa, Wisconsin 53226
> Email: 78GMC-Royale@att.net
> 414-745-3188
> Web Site: http://ray-lisa.page.tl/
>
>
>
>
> ________________________________
> From: Emery Stora <emerystora@mac.com>
> To: gmclist@temp.gmcnet.org
> Sent: Thu, June 28, 2012 10:24:45 AM
> Subject: Re: [GMCnet] Duracool installation pressures
>
> Some additional information:
>
> If you use 3 six ounce cans of Duracool you will be very close to the proper
> charge. I have found that with the low humidity in NM I actually use a little

> less. Once you have the three cans in you can check your pressure and decide
>if
>
> you want to bleed off a little.
>
> Emery Stora
>
> On Jun 28, 2012, at 9:20 AM, Emery Stora wrote:
>
>> I think that some clarification is necessary regarding the low side pressure of
>>
>> Duracool.
>>
>> Many have been quoting my statement that a pressure of 20 psi at 1500 RPM is
>> the correct target for installation of Duracool.
>>
>> HOWEVER, they do not give the whole story. When I first suggested this
>> pressure on the GMCnet back in 2002 I had also said that this depends on the
>> humidity where you use the GMC. I said that in high humidity conditions you
>> might have to put in more Duracool in order to prevent freezing up of your
>> evaporator coil. The next year I reported that on a trip to Florida I
>> experienced this problem as there was very high humidity. I added a little
>>more
>>
>> Duracool and the problem went away. This gave me a pressure of about 25 psi.
>>
>> However, when I returned to NM and when I traveled to Arizona I found that I
>> could get colder air conditioning if I went back to 20 psi. I could do this is
>>
>> because of the low humidity in those states.
>>
>> I have also stated that the 20 psi target was with ambient temperatures of
>> perhaps 90 and less. If the outside temperature is higher the pressure in the
>
>> system will be higher so it might be necessary to add Duracool until the
>> pressure was at 25 or so psi. You are not actually using any more Duracool but
>>
>> the measurement of the pressure in the system will be higher due to the higher
>
>> temperatures. So, if you install it at, say 90 deg, to a 20 psi level and then
>>
>> later check the pressure when it is 100 or more you will find that there is
>> indeed higher pressures in the system. So, if you are installing it at 100 deg
>>
>> and only put in 20 psi then you could possibly be undercharged at lower ambient
>>
>> temperatures.
>>
>> If you have freezing of the evaporator you will know it. The humid air will
>> cause ice to form on the fins in your heater box evaporator coil. When enough
>
>> ice forms it will completely block the air flow through the coil. When this
>> happened to me I thought that my blower motor had failed. To thaw the coils
>>you
>>
>> can turn off the air conditioner but keep the fan on high. This will soon melt
>>
>> the ice and you will again get air flow through the air conditioning outlets.
>
>> However, it will freeze up again after a while when you turn the air
>>conditioner
>>
>> on again.
>>
>> Emery Stora
>>
>>
>
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Ray Erspamer 78 GMC Royale Center Kitchen 403, 3.70 Final Drive Holley Sniper Quadrajet EFI System, Holley Hyperspark Ignition System 414-484-9431
Re: [GMCnet] Duracool installation pressures [message #174963 is a reply to message #174890] Thu, 28 June 2012 20:59 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
It would be a help if somebody would weigh the amount of various refrigerants to get a given suction pressure out of the GMC A/C. 
 
--johnny
'76 23' transmode norria
'76 palm beach
 

From: Emery Stora <emerystora@mac.com>
To: gmclist@temp.gmcnet.org
Sent: Thursday, June 28, 2012 11:20 AM
Subject: [GMCnet] Duracool installation pressures

I think that some clarification is necessary regarding the low side pressure of Duracool.

Many have been quoting my statement that a pressure of 20 psi at 1500 RPM is the correct target for installation of Duracool.

HOWEVER, they do not give the whole story.  When I first suggested this pressure on the GMCnet back in 2002 I had also said that this depends on the humidity where you use the GMC.  I said that in high humidity conditions you might have to put in more Duracool in order to prevent freezing up of your evaporator coil.  The next year I reported that on a trip to Florida I experienced this problem as there was very high humidity.  I added a little more Duracool and the problem went away.  This gave me a pressure of about 25 psi.

However, when I returned to NM and when I traveled to Arizona I found that I could get colder air conditioning if I went back to 20 psi.  I could do this is because of the low humidity in those states.

I have also stated that the 20 psi target was with ambient temperatures of perhaps 90 and less.  If the outside temperature is higher the pressure in the system will be higher so it might be necessary to add Duracool until the pressure was at 25 or so psi.  You are not actually using any more Duracool but the measurement of the pressure in the system will be higher due to the higher temperatures.  So, if you install it at, say 90 deg, to a 20 psi level and then later check the pressure when it is 100 or more you will find that there is indeed higher pressures in the system.  So, if you are installing it at 100 deg and only put in 20 psi then you could possibly be undercharged at lower ambient temperatures.

If you have freezing of the evaporator you will know it.  The humid air will cause ice to form on the fins in your heater box evaporator coil.  When enough ice forms it will completely block the air flow through the coil.  When this happened to me I thought that my blower motor had failed.  To thaw the coils you can turn off the air conditioner but keep the fan on high.  This will soon melt the ice and you will again get air flow through the air conditioning outlets.  However, it will freeze up again after a while when you turn the air conditioner on again.

Emery Stora


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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] Duracool installation pressures [message #174967 is a reply to message #174963] Thu, 28 June 2012 21:05 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member
That would be quite an undertaking. Why don't you take on the project??? That "somebody" could be you!!!

Emery Stora

On Jun 28, 2012, at 7:59 PM, Johnny Bridges wrote:

> It would be a help if somebody would weigh the amount of various refrigerants to get a given suction pressure out of the GMC A/C.
>
> --johnny
> '76 23' transmode norria
> '76 palm beach
>
>
> From: Emery Stora <emerystora@mac.com>
> To: gmclist@temp.gmcnet.org
> Sent: Thursday, June 28, 2012 11:20 AM
> Subject: [GMCnet] Duracool installation pressures
>
> I think that some clarification is necessary regarding the low side pressure of Duracool.
>
> Many have been quoting my statement that a pressure of 20 psi at 1500 RPM is the correct target for installation of Duracool.
>
> HOWEVER, they do not give the whole story. When I first suggested this pressure on the GMCnet back in 2002 I had also said that this depends on the humidity where you use the GMC. I said that in high humidity conditions you might have to put in more Duracool in order to prevent freezing up of your evaporator coil. The next year I reported that on a trip to Florida I experienced this problem as there was very high humidity. I added a little more Duracool and the problem went away. This gave me a pressure of about 25 psi.
>
> However, when I returned to NM and when I traveled to Arizona I found that I could get colder air conditioning if I went back to 20 psi. I could do this is because of the low humidity in those states.
>
> I have also stated that the 20 psi target was with ambient temperatures of perhaps 90 and less. If the outside temperature is higher the pressure in the system will be higher so it might be necessary to add Duracool until the pressure was at 25 or so psi. You are not actually using any more Duracool but the measurement of the pressure in the system will be higher due to the higher temperatures. So, if you install it at, say 90 deg, to a 20 psi level and then later check the pressure when it is 100 or more you will find that there is indeed higher pressures in the system. So, if you are installing it at 100 deg and only put in 20 psi then you could possibly be undercharged at lower ambient temperatures.
>
> If you have freezing of the evaporator you will know it. The humid air will cause ice to form on the fins in your heater box evaporator coil. When enough ice forms it will completely block the air flow through the coil. When this happened to me I thought that my blower motor had failed. To thaw the coils you can turn off the air conditioner but keep the fan on high. This will soon melt the ice and you will again get air flow through the air conditioning outlets. However, it will freeze up again after a while when you turn the air conditioner on again.
>
> Emery Stora
>
>
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Re: [GMCnet] Duracool installation pressures [message #174969 is a reply to message #174901] Thu, 28 June 2012 21:10 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
Emory -
 
Where did you mount the second evap?
 
--johnny
'76 23' trandmode norris
'76 palm beach

From: Emery Stora <emerystora@mac.com>
To: "gmclist@temp.gmcnet.org" <gmclist@temp.gmcnet.org>
Sent: Thursday, June 28, 2012 12:08 PM
Subject: Re: [GMCnet] Duracool installation pressures

I have an additional 18,000 btu evaporator and 3 cans still work fine.

After going through the expansion valve the evaporator is essentially filled with vapor so it really doesn't take much, if any, more liquid Duracool.

Emery Stora

On Jun 28, 2012, at 10:04 AM, "A." <markbb1@netzero.com> wrote:

>
>
> Anybody running Duracool in a system with multiple evaporators?  How much Duracool did it take to get the pressure right?
> --
> '73 23' CanyonLands
> _______________________________________________
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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] Duracool installation pressures [message #174973 is a reply to message #174969] Thu, 28 June 2012 21:30 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member
I think that I did this about 8 years ago and posted pictures and instructions and parts list here:

http://www.gmcmhphotos.com/photos/g3356-aux-air-conditioner-evaporator.html

Emery Stora

On Jun 28, 2012, at 8:10 PM, Johnny Bridges wrote:

> Emory -
>
> Where did you mount the second evap?
>
> --johnny
> '76 23' trandmode norris
> '76 palm beach
>
> From: Emery Stora <emerystora@mac.com>
> To: "gmclist@temp.gmcnet.org" <gmclist@temp.gmcnet.org>
> Sent: Thursday, June 28, 2012 12:08 PM
> Subject: Re: [GMCnet] Duracool installation pressures
>
> I have an additional 18,000 btu evaporator and 3 cans still work fine.
>
> After going through the expansion valve the evaporator is essentially filled with vapor so it really doesn't take much, if any, more liquid Duracool.
>
> Emery Stora
>
> On Jun 28, 2012, at 10:04 AM, "A." <markbb1@netzero.com> wrote:
>
>>
>>
>> Anybody running Duracool in a system with multiple evaporators? How much Duracool did it take to get the pressure right?
>> --
>> '73 23' CanyonLands
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> _______________________________________________
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Re: [GMCnet] Duracool installation pressures [message #174975 is a reply to message #174967] Thu, 28 June 2012 21:39 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
I don't have a service scale... wish I did, but not $200 worth.
 
--johnny
'76 23' transmode norris
'76 palm beach
 

From: Emery Stora <emerystora@mac.com>
To: gmclist@temp.gmcnet.org
Sent: Thursday, June 28, 2012 10:05 PM
Subject: Re: [GMCnet] Duracool installation pressures

That would be quite an undertaking.  Why don't you take on the project???  That "somebody" could be you!!!

Emery Stora

On Jun 28, 2012, at 7:59 PM, Johnny Bridges wrote:

> It would be a help if somebody would weigh the amount of various refrigerants to get a given suction pressure out of the GMC A/C. 

> --johnny
> '76 23' transmode norria
> '76 palm beach

>
> From: Emery Stora <emerystora@mac.com>
> To: gmclist@temp.gmcnet.org
> Sent: Thursday, June 28, 2012 11:20 AM
> Subject: [GMCnet] Duracool installation pressures
>
> I think that some clarification is necessary regarding the low side pressure of Duracool.
>
> Many have been quoting my statement that a pressure of 20 psi at 1500 RPM is the correct target for installation of Duracool.
>
> HOWEVER, they do not give the whole story.  When I first suggested this pressure on the GMCnet back in 2002 I had also said that this depends on the humidity where you use the GMC.  I said that in high humidity conditions you might have to put in more Duracool in order to prevent freezing up of your evaporator coil.  The next year I reported that on a trip to Florida I experienced this problem as there was very high humidity.  I added a little more Duracool and the problem went away.  This gave me a pressure of about 25 psi.
>
> However, when I returned to NM and when I traveled to Arizona I found that I could get colder air conditioning if I went back to 20 psi.  I could do this is because of the low humidity in those states.
>
> I have also stated that the 20 psi target was with ambient temperatures of perhaps 90 and less.  If the outside temperature is higher the pressure in the system will be higher so it might be necessary to add Duracool until the pressure was at 25 or so psi.  You are not actually using any more Duracool but the measurement of the pressure in the system will be higher due to the higher temperatures.  So, if you install it at, say 90 deg, to a 20 psi level and then later check the pressure when it is 100 or more you will find that there is indeed higher pressures in the system.  So, if you are installing it at 100 deg and only put in 20 psi then you could possibly be undercharged at lower ambient temperatures.
>
> If you have freezing of the evaporator you will know it.  The humid air will cause ice to form on the fins in your heater box evaporator coil.  When enough ice forms it will completely block the air flow through the coil.  When this happened to me I thought that my blower motor had failed.  To thaw the coils you can turn off the air conditioner but keep the fan on high.  This will soon melt the ice and you will again get air flow through the air conditioning outlets.  However, it will freeze up again after a while when you turn the air conditioner on again.
>
> Emery Stora
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
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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] Duracool installation pressures [message #174977 is a reply to message #174973] Thu, 28 June 2012 21:42 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
Thanks!  wasn';t here at the time.  That's a good looking install.
 
--johnny
 
'76 23' trandmode norris
'76 palm beach

From: Emery Stora <emerystora@mac.com>
To: gmclist@temp.gmcnet.org
Sent: Thursday, June 28, 2012 10:30 PM
Subject: Re: [GMCnet] Duracool installation pressures

I think that I did this about 8 years ago and posted pictures and instructions and parts list here:

http://www.gmcmhphotos.com/photos/g3356-aux-air-conditioner-evaporator.html

Emery Stora

On Jun 28, 2012, at 8:10 PM, Johnny Bridges wrote:

> Emory -

> Where did you mount the second evap?

> --johnny
> '76 23' trandmode norris
> '76 palm beach
>
> From: Emery Stora <emerystora@mac.com>
> To: "gmclist@temp.gmcnet.org" <gmclist@temp.gmcnet.org>
> Sent: Thursday, June 28, 2012 12:08 PM
> Subject: Re: [GMCnet] Duracool installation pressures
>
> I have an additional 18,000 btu evaporator and 3 cans still work fine.
>
> After going through the expansion valve the evaporator is essentially filled with vapor so it really doesn't take much, if any, more liquid Duracool.
>
> Emery Stora
>
> On Jun 28, 2012, at 10:04 AM, "A." <markbb1@netzero.com> wrote:
>
>>
>>
>> Anybody running Duracool in a system with multiple evaporators?  How much Duracool did it take to get the pressure right?
>> --
>> '73 23' CanyonLands
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> _______________________________________________
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> Unsubscribe or Change List Options:
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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] Duracool installation pressures [message #174978 is a reply to message #174963] Thu, 28 June 2012 22:16 Go to previous messageGo to next message
Dennis S is currently offline  Dennis S   United States
Messages: 3046
Registered: November 2005
Karma: 2
Senior Member
Johnny Bridges wrote on Thu, 28 June 2012 20:59

It would be a help if somebody would weigh the amount of various refrigerants to get a given suction pressure out of the GMC A/C. 
 
--johnny
'76 23' transmode norria
'76 palm beach




Having never used Duracool -- but I thought a "six ounce" can of Duracool was a weight -- rather than a volume?


Dennis


Dennis S
73 Painted Desert 230
Memphis TN Metro
Re: [GMCnet] Duracool installation pressures [message #174982 is a reply to message #174978] Thu, 28 June 2012 22:50 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Dennis,

Click on link below and go to page 4:

http://www.duracool.com/Duracool_Parts_and_Accessories_2006_Catalogue_LR.pdf

Regards,
Rob M.

-----Original Message-----
From: Dennis Sexton

Having never used Duracool -- but I thought a "six ounce" can of Duracool was a weight -- rather than a volume?

Dennis

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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] Duracool installation pressures [message #174985 is a reply to message #174982] Thu, 28 June 2012 23:12 Go to previous messageGo to next message
Dennis S is currently offline  Dennis S   United States
Messages: 3046
Registered: November 2005
Karma: 2
Senior Member
Rob,

Thank you -- good information, and I also found this --

DURACOOLŽ products are extremely efficient. DURACOOL 12aŽ requires only 35% of the charge, by weight, of CFC-12 (R-12), or 40% of the charge, by weight of HFC-134a (R-134a). DURACOOL 22aŽ and DURACOOL 502aŽ require only 40% of the charge, by weight, of R-22 and R-502, respectively. This is interpreted as follows:

DURACOOL 12aŽ
6 ounce can = 17 ounces of CFC-12 (R-12) or 15 ounces of HFC-134a.


Dennis

Robert Mueller wrote on Thu, 28 June 2012 22:50

Dennis,

Click on link below and go to page 4:

http://www.duracool.com/Duracool_Parts_and_Accessories_2006_Catalogue_LR.pdf

Regards,
Rob M.

-----Original Message-----
From: Dennis Sexton

Having never used Duracool -- but I thought a "six ounce" can of Duracool was a weight -- rather than a volume?

Dennis

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Dennis S
73 Painted Desert 230
Memphis TN Metro
Re: [GMCnet] Duracool installation pressures [message #174987 is a reply to message #174975] Fri, 29 June 2012 01:29 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
Johnny Bridges wrote on Thu, 28 June 2012 21:39

I don't have a service scale... wish I did, but not $200 worth.
 
--johnny
'76 23' transmode norris
'76 palm beach



You do not need one. I use a Harbor Freight one for my 30 pound container of R-134. Set the container on the scale and watch the numbers.

For Gene "Harbor Freight tools are junk"

But this scale suits my needs.

http://www.harborfreight.com/70-lb-32-kg-digital-postal-scale-95069.html

I think I paid $29.00 on sale for it a couple of years ago.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Duracool installation pressures [message #175016 is a reply to message #174963] Fri, 29 June 2012 11:19 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
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Senior Member
[quote title=Johnny Bridges wrote on Thu, 28 June 2012 18:59]It would be a help if somebody would weigh the amount of various refrigerants to get a given suction pressure out of the GMC A/C. 
 
--johnny
'76 23' transmode norria
'76 palm beach
 

Good luck getting an accurate weight for Duracool.


Roy Keen Minden,NV 76 X Glenbrook
Re: [GMCnet] Duracool installation pressures [message #175020 is a reply to message #175016] Fri, 29 June 2012 11:35 Go to previous messageGo to previous message
C Boyd is currently offline  C Boyd   United States
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Gentlemen: As you know my learnen comes from the shade tree and not many books. An old ac man that dad worked with came to the house in my young days and was chargings Moms ac in her Olds. I asked him how did he know how much freon to add? He splained to me about how acs can have slightly different size orifaces and how some compressors are better than others then said if the inlet hose to the compressor is sweating that particular ac is doing the best it can. So even using gauges I charge it till the line is sweating at the compressor. He also said you need a fan blowing on the condensor when charging at 1200-1500 rpm.
your milage may vary..




[quote title=roy1 wrote on Fri, 29 June 2012 12:19]
Johnny Bridges wrote on Thu, 28 June 2012 18:59

It would be a help if somebody would weigh the amount of various refrigerants to get a given suction pressure out of the GMC A/C. 
 
--johnny
'76 23' transmode norria
'76 palm beach
 

Good luck getting an accurate weight for Duracool.



C. Boyd
76 Crestmont
East Tennessee
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