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Old 12-13-2007, 05:48 PM   #1
jpabberton
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AC Help-what is this?

Can anyone tell me what this is called? When I jump it the compressor runs but when I take the jumper out and plug the harness in to the switch nothing happens. I had the system recharged. I adjusted the screw. Can I take this out without draining the system? Can I purchase this at a parts store? Summers coming and I need AC (I live in Phoenix).
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Old 12-13-2007, 05:55 PM   #2
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Re: AC Help-what is this?

It's a binary pressure switch. It it supposed to prevent the compressor from running when the pressure is to low or to high.

R/
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Old 12-13-2007, 06:18 PM   #3
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Re: AC Help-what is this?

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Originally Posted by Hart_Rod View Post
It's a binary pressure switch. It it supposed to prevent the compressor from running when the pressure is to low or to high.

R/

WHAT HE SIAD IS EXACTLY RIGHT. ITS AN A/C PRESSURE SWITCH DESIGNED TO HELP PROTECT THE COMPRESSOR
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Old 12-13-2007, 06:31 PM   #4
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Re: AC Help-what is this?

Its called a low pressure switch at the parts store if you ever want to replace it.
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Old 12-13-2007, 06:33 PM   #5
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Re: AC Help-what is this?

Thanks. When I remove it will all the freon leak out? Do they go bad?
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Old 12-13-2007, 06:36 PM   #6
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Re: AC Help-what is this?

They do go bad. Usually they are removable and have a schraeder valve, so you won't have any leaks with it removed.
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Old 12-13-2007, 06:36 PM   #7
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Re: AC Help-what is this?

if they over or under pressurized your system, thats why its not kicking on. Sometimes when youre charging your system you jumper that switch so that your compressor will kick on and suck in the R143a refrigerant
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Old 12-14-2007, 09:56 PM   #8
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Re: AC Help-what is this?

Those switches are bad for failing. I've put 3 on the 71 since recharging it this past spring. All three were new too!
No it want loose the charge when taken off.
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Get out and drive the truck this summer and have some fun!
It sucks not being able to hear!

LWB trucks rule, if you don't think so measure your SWB!
After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.
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Old 12-15-2007, 01:11 AM   #9
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Re: AC Help-what is this?

Isnt that a POA eliminator kit?
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Old 12-19-2007, 06:49 PM   #10
jpabberton
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Re: AC Help-what is this?

After some grief I got a new switch at the parts store, but the threads were fine and mine threads are coarse. I found another one and replaced it, $9.00. Make sure the plastic is black in color, not white. I think the white has the fine threads.

Anyways, it nows runs intermittedly. What does the screw adjustment do?

Thanks for the help.
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Old 12-19-2007, 11:58 PM   #11
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Re: AC Help-what is this?

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Originally Posted by oldspowered67C10 View Post
Isnt that a POA eliminator kit?
That's what it looks like to me. Some one removed the POA and replaced it with the kit. With that kit, the switch controls the evaporator pressure by turning the compressor on and off. Has anyone with one of those kits ever used a relay in the circut to the clutch? The amp load from the clutch is pretty high, and that might be causing repeat switch failures.
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Last edited by Bob B.; 12-20-2007 at 12:01 AM.
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Old 12-20-2007, 02:21 AM   #12
Andy4639
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Re: AC Help-what is this?

Here is what I did. Bought a acumalator with the low pressure switch already installed. It screw's right into the tube coming out of the evaperator box. I cut just enough of the bracket that held the POA assembly orignally to hold the acumlator. I also took the drier out of the system. That is 30 year old technology and I decided to update the system to 134-A too. It works great!

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1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver
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2013,14 and 2016 Hot Rod Pour Tour


http://upstategmtrucks.com/



Get out and drive the truck this summer and have some fun!
It sucks not being able to hear!

LWB trucks rule, if you don't think so measure your SWB!
After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.

Last edited by Andy4639; 12-20-2007 at 02:24 AM.
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