Go Back   Ford Truck Enthusiasts Forums > Misc. > Cooling, Heating, Ventilation & A/C
Sign in using an external account
Register Forgot Password?


Welcome to Ford-Trucks Forums!
Welcome to Ford-Trucks.com.

You are currently viewing our forums as a guest, which gives you limited access to view most discussions and access our other features. By joining our community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join the Ford-Trucks Forums community today!





 
Reply
 
 
 
 
LinkBack Thread Tools Search this Thread
  #1  
Old 06-05-2006, 04:45 PM
surveyguy surveyguy is offline
Senior User
 
Join Date: Jun 2006
Posts: 372
surveyguy is starting off with a positive reputation.
how much refrigerant?

Just installed A/C in my F150. Came out of an '87, I have a '94. I replaced the o-rings, and charged it up with 30 oz of 134 and oil. Anyone know if I should go for 20# 30#, 40# on the low side? So far it's cool, but not ice-cold. Also, it is cycled on 100% of the time right now. It cycled on-and-off while I was putting in the R134, but after I got about 20 oz in, it stayed on continually.

Last edited by surveyguy; 06-05-2006 at 05:10 PM.
Reply With Quote
  #2  
Old 06-06-2006, 12:01 PM
rusty70f100 rusty70f100 is offline
Post Fiend
 
Join Date: Jan 2003
Location: Iowa
Posts: 8,600
rusty70f100 is gaining momentum as a positive member of FTE.rusty70f100 is gaining momentum as a positive member of FTE.
The pressure on the low side depends on the ambient temperature. I'd put a thermometer in front of the grille and measure it there.

Here's the information from the chart that I have:

Degrees (F) / Low side gauge pressure

65F / 25-35psi
70F / 35-40psi
75F / 35-45psi
80F / 40-50psi
85F / 45-55psi
90F / 45-55psi
95F / 50-55psi
100+F / 50-55psi

Usually what I just do though, is charge until it doesn't cycle going down the highway with the AC on full blast.

Also there's a low pressure cycling switch, that should plug into a port on the accumulator / drier. This has an adjustment screw between the two prongs. I believe for a retrofitted R12 system you want to turn that out (counterclockwise) approximately one turn. I'd do that first, then charge.
Reply With Quote
  #3  
Old 06-06-2006, 03:22 PM
surveyguy surveyguy is offline
Senior User
 
Join Date: Jun 2006
Posts: 372
surveyguy is starting off with a positive reputation.
ah, thanks! I charged it to about 25# at about 70F last night. It wouldn't cycle off very often on full blast sitting in the driveway with the accellorator pressed a little bit. I will turn out that screw a little bit and give it a try before adding more r134
Reply With Quote
  #4  
Old 06-06-2006, 04:13 PM
CowboyBilly9Mile's Avatar
CowboyBilly9Mile CowboyBilly9Mile is offline
Post Fiend
 
Join Date: Feb 2003
Location: Eastern WA
Posts: 6,940
CowboyBilly9Mile is a name known to allCowboyBilly9Mile is a name known to allCowboyBilly9Mile is a name known to allCowboyBilly9Mile is a name known to allCowboyBilly9Mile is a name known to allCowboyBilly9Mile is a name known to all
Careful as you tweak that low pressure cutout switch. The reason is because, at the typical suction side pressure of around 35psi, the evap core temp is roughly the same. You drop that suction side pressure down (and thus the temp) and hold it there too long and you will turn the evaporator into a block of ice. The odds of this happening will increase on humid days as well as cooler days.
Reply With Quote
  #5  
Old 06-06-2006, 04:16 PM
surveyguy surveyguy is offline
Senior User
 
Join Date: Jun 2006
Posts: 372
surveyguy is starting off with a positive reputation.
ok, well, in the 5 minutes I had it running, the accumulator was frosting up pretty good. Maybe I'll leave it there. I just wonder why it was not cycling on and off, just seems to stay on 90% of the time. I'll take it for a test drive tonight and see if it cycles on-and-off.
Reply With Quote
  #6  
Old 06-06-2006, 06:04 PM
mantta's Avatar
mantta mantta is offline
Posting Guru
 
Join Date: Feb 2001
Location: Keweenaw Bay, MI
Posts: 1,721
mantta is gaining momentum as a positive member of FTE.
If the accumulator is frosting up it is still low on refrigerant. It should be cold and have condensation building up on it but not frosted. If it frosts up, your evaporator will freeze and all the condensate that builds up and freezes will stop the air flow.
__________________
ENCS(SS), (SW), USN RET (E-8)
Keweenaw Bay, MI
U.S. Navy (Submarine Service) 60-80
2010 Ford F-150 4WD Lariat Ext Cab
1999 Lincoln Town Car Ecec Series
1930 Model "A" Coupe
Reply With Quote
  #7  
Old 06-07-2006, 10:07 AM
surveyguy surveyguy is offline
Senior User
 
Join Date: Jun 2006
Posts: 372
surveyguy is starting off with a positive reputation.
ah, thanks! I put one more can in last night. When it is on (compressor clutch engaged) it's reading about 30# now. Maybe still more? Compressor still running 100% of the time, even when I drove down the road last night. That is at 65 degrees outside. Thanks so much everyone!!
Reply With Quote
  #8  
Old 06-07-2006, 10:22 AM
mantta's Avatar
mantta mantta is offline
Posting Guru
 
Join Date: Feb 2001
Location: Keweenaw Bay, MI
Posts: 1,721
mantta is gaining momentum as a positive member of FTE.
I hope you pulled a good vacuum on it before you charged it. My 88 holds 52 ounces of refrigeran (3.25 lbs). That is from the shop manual.
__________________
ENCS(SS), (SW), USN RET (E-8)
Keweenaw Bay, MI
U.S. Navy (Submarine Service) 60-80
2010 Ford F-150 4WD Lariat Ext Cab
1999 Lincoln Town Car Ecec Series
1930 Model "A" Coupe
Reply With Quote
  #9  
Old 06-07-2006, 10:47 AM
surveyguy surveyguy is offline
Senior User
 
Join Date: Jun 2006
Posts: 372
surveyguy is starting off with a positive reputation.
what will you loose if you don't pull a vacuum, just volume of refrigerant? I have 50oz in it right now.
Reply With Quote
  #10  
Old 06-07-2006, 11:39 AM
jtmerritt jtmerritt is offline
Senior User
 
Join Date: Feb 2003
Location: Cincinnati, Ohio
Posts: 494
jtmerritt is starting off with a positive reputation.
If you don't pull a vacuum you run the risk of air and moisture in the system which besides displacing freon and reducing overall cooling will react with the freon and eventually kill the compressor.

John
__________________
99.5 XLT PSD SC SB 4X4 Woodland Green.
Reply With Quote
  #11  
Old 06-07-2006, 11:42 AM
mantta's Avatar
mantta mantta is offline
Posting Guru
 
Join Date: Feb 2001
Location: Keweenaw Bay, MI
Posts: 1,721
mantta is gaining momentum as a positive member of FTE.
It is not a good idea to put refrigerant into an empty system without pulling a vacuum because;
1. There will be air in the system that will not condense and it will cause your compressor discharge pressure to be very high.
2. The air in the system will cause oxidents and acids in the system that will corrode internal parts of the compressor.
3. Air in the system has moisture in it and that moisture will condense into waterin the system and the water will emulsify the oil in the compressor.
__________________
ENCS(SS), (SW), USN RET (E-8)
Keweenaw Bay, MI
U.S. Navy (Submarine Service) 60-80
2010 Ford F-150 4WD Lariat Ext Cab
1999 Lincoln Town Car Ecec Series
1930 Model "A" Coupe
Reply With Quote
  #12  
Old 06-07-2006, 11:43 AM
surveyguy surveyguy is offline
Senior User
 
Join Date: Jun 2006
Posts: 372
surveyguy is starting off with a positive reputation.
ew boy, thanks!
Reply With Quote
Old 06-07-2006, 11:43 AM
 
 
 
Reply

Go Back   Ford Truck Enthusiasts Forums > Misc. > Cooling, Heating, Ventilation & A/C

Tags
1987, 1999, 2003, 2006, 351, 54, ac, e150, expedition, f150, ford, hold, quantity, r134a, refrigerant, volume

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

Forum Jump



All times are GMT -5. The time now is 01:07 PM.


Powered by vBulletin® Version 3.8.7 AC1
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Advertising - Terms of Use - Privacy Statement - Jobs
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. FordŽ is a registered trademark of the Ford Motor Company.

vbulletin Admin Backup