Home Ford Ranger Forum Tech Articles Other Articles Featured Rangers Readers Rangers Classifieds Shirts & Decals Parts Store

Ford Ranger Discussion Forum  

Go Back   The Ranger Station Forums > Help Forums - Styling & Electrical > Heating & Air Conditioning

Reply
 
Thread Tools Display Modes
Old 02-10-2010, 06:45 PM   #1
Little Red
Junior Member
 
Join Date: Sep 2008
Posts: 60
Vehicle Year: 1997 2000
Vehicle Make: Ford
Vehicle Model: Ranger, All stock F150 XLT
I use this vehicle for: Daily Trans.
Rep Power: 19
Little Red is on a distinguished road
Default A/C compressor question

It's in the teens outside and my compressor is running while in defrost or blending with floor heat. My owners guide says it shouldn't run under 50 deg. Where is the thermostat or temp control for the clutch? I wonder if someone didn't just bypass it. I'm the 2nd owner but I don't know who worked on it before. Thanks
Little Red is offline   Reply With Quote
Forum Notices (Not shown to 'Premium Members')

 SPRING ONLINE MAGAZINE!

 Check out the latest articles

 Want to become a Premium Member & not see these notices? Click HERE.

Old 02-10-2010, 08:57 PM   #2
LittleHorse
Member
 
LittleHorse's Avatar
 
Join Date: Jan 2009
Location: Pryor, OK
Posts: 964
Vehicle Year: 1990
Vehicle Make: Ford
Vehicle Model: Bronco II
I use this vehicle for: Staining my Driveway
Rep Power: 19
LittleHorse is on a distinguished road
Default

a lot of newer systems run the compressor during defrost because

A) it keeps oil on the seals so they don't shrink up and leak

and

B) by running the compressor, your evaporator is causing moisture in your cab to condense on it and drain out the bottom of the evap box. This reduces enhances the defrost by reducing the amount of water that is available to condense on your windshield and windows.

There is a low pressure switch near the accumulator that will cut off the compressor if the suction pressure gets low enough that the compressor shouldn't operate. There's a possibility that someone could have bypassed it if the switch broke and wasn't allowing the AC to come on. I'm not familiar with the layout on a '97 but on my '90 the accumulator is right in front of the evaporator/heater box and the switch is right in the line coming out of the top of the accumulator. If the switch has nothing plugged into it or you find the plug with a jumper, then it's been bypassed. If it's not bypassed, you shouldn't have anything to worry about.


I'm an engineer for a manufacturer of commercial and industrial air conditioning systems, in case you were wondering whether this random guy on the internet knows what he's talking about.
__________________
Joe - 2005 Jeep LWB TJ - 2006 Toyota Matrix XR
Quote:
Originally Posted by AllanD
If you wanna be weirded out look at the mechanical details of the way cats fornicate.
LittleHorse is offline   Reply With Quote
Old 02-10-2010, 09:18 PM   #3
Little Red
Junior Member
 
Join Date: Sep 2008
Posts: 60
Vehicle Year: 1997 2000
Vehicle Make: Ford
Vehicle Model: Ranger, All stock F150 XLT
I use this vehicle for: Daily Trans.
Rep Power: 19
Little Red is on a distinguished road
Default

I'm an ex HVAC tech myself and also a shadetree mechanic. Went to GM Training Center in Pittsburgh when I was younger so I know what you're talking about. I didn't want to try to show what I know(which humbley.. a lot of people know more). I know some vehicles definately have a temp switch and my owners guide says my 97 has one but I can't find it.My Chiltons don't show it in the wiring diagrams. I know why the Compressor runs in defrost mode also. I'm a little rusty so I guess I'll have to trace the wiring out and see. I just don't see an A/C system working efficiently in the teens when it is designed to work at it's best when it's summertime.I guess a little dehumidifying is helpful anyway.Thanks for your post. Anybody else?
Little Red is offline   Reply With Quote
Old 02-11-2010, 07:54 AM   #4
Little Red
Junior Member
 
Join Date: Sep 2008
Posts: 60
Vehicle Year: 1997 2000
Vehicle Make: Ford
Vehicle Model: Ranger, All stock F150 XLT
I use this vehicle for: Daily Trans.
Rep Power: 19
Little Red is on a distinguished road
Default

Littlehorse, I found this on my Ford CD that I forgot I had. See, I told you I'm gettin' rusty. Now I know where to look.
(The A/C cycling switch (19E561) is mounted on a Schrader valve-type fitting on the side of the suction accumulator/drier (19C836) in Aerostar vehicles, and on the top of the suction accumulator/drier in Ranger and Explorer vehicles. A valve depressor, located inside the threaded end of the A/C cycling switch, depresses the Schrader valve stem as the A/C cycling switch is mounted and allows the suction pressure inside the accumulator/drier housing to control operation. The electrical contacts are normally open when the suction pressure is at or below 231 psi; they will close when the suction pressure rises to approximately 40-60 psi or above. Lower ambient temperatures (below 8C or 46F), during cold weather seasons, will also open the contacts due to the pressure/temperature relationship of the refrigerant in the system.) The compressor cycles normally in summer so the switch is functioning. Why it won't open in winter is the question. No big deal, just cabin fever setting in. I need something to tinker with.
Little Red is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

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 Off

Forum Jump




All times are GMT -5. The time now is 06:38 PM.




1999-2014 / 959 Media LLC / All Rights Reserved