When my ac or heat is on something under the hood clicks on and off every 30 seconds or so... Any thoughts on what it could be?

 

Thats your compressor clicking

 

What would make it click if the ac blows cold and everything works fine. I know that they click when they are low or to full on freon but i dont think that is the case.

 

Im not sure what causes it, i just know my old 94' did it and everything ran fine

 

My truck has done it for 70,000 miles (since I bought it) and I have not had any problems with my A/C. I think its supposed to do it...i think...

 

the ac pump doesnt run all the time it has a clutch system in it so the pulley can turn with out turning the ac pump

 

What is the outside air temp? If it is cool then there will no be effective heat transfer in the evaporator. The colder it gets, the more this will happen. It is normal for it to cycle on and off frequently in the cold weather. Cold does not have to be 32 deg either. 60 deg will cycle the compressor frequently.

 

Well I have only had it a few months so weather was cool..

 

The a/c pump will come on and stay on to cool the cab off, once it cools the cab off it will cycle on and off to keep the air cool and dry.If its very cool where you are them the compressor doesn't need to stay on all the time so it just cycles.

 

You have nothing to worry about. Now if the cab was not cooling down it would indicate you were low on freon.

 

wtf are you talking about that is total bs. the rangers dont have limit control.


what i said above is correct

 

The A/C compressor cycles because the a/c pressure (ACP) switch tells it to so the evaporator doesnt freeze. if there is high load on the system (warm or humid day) the pressure drops slower so it cycles longer. if the system is low on charge or there is low load on the system, the compressor cycles fast

A valve depressor, located inside the threaded end of the A/C cycling switch, presses in on the Schrader valve stem.
This allows the suction pressure inside the suction accumulator/drier to control the operation of the A/C cycling switch.
The electrical switch contacts open when the suction pressure drops to 152-193 kPa (22-28 psi).
The contacts close when the suction pressure rises to 276-324 kPa (40-47 psi).
When the A/C cycling switch contacts close, the signal to energize the A/C clutch is sent to the wide open throttle A/C cutoff relay.
When the A/C cycling switch contacts open, the A/C clutch field coil is deenergized and compressor operation stops.
The A/C cycling switch will control the A/C evaporator core pressure at a point where the plate/fin surface temperature will be maintained slightly above freezing.
This prevents icing of the A/C evaporator core and blockage of airflow.

 

^^^ thank you lol they probably wont understand that to technical lol

 

Of course all that happens simply put because at lower temps there is a less efficient heat exchange in the condenser and evaporator. I am a former NAVY refrigeration tech and you lost me.

You are correct though.

 

lol, those are not my words, they are straight out of the 1999 ranger workshop manual. i was trying to explain it in my words but i failed and deleted it

 

here

https://www.ranger-forums.com/f15/g-m-c-switch-94174/

 

It was absoutely correct. I am just wondering, when's the test. I feel so unprepared.

 

haha...i had a 250 question final on a/c two weeks ago...i still have it memorized, just cant word it like the manual

 

god i dont look forward to that test i will be having you take the online test for me

 

Nice

 

you dont take those online...haha

 

o god

 

LOL