Can someone tell me what the normal operation is like for the A/C compressor clutch?

I just went out and turned on the truck and then the AC (Max). The compressor clutch kicks on and off about 5 times and then stays on for the 6th. It did this on 3 consecutive attempts at turning A/C from OFF to Max A/C.

Is this normal or should it go on the first time and stay on?

 

The A/C compressor clutch is cycled on and off based on system pressure to maintain an evaporator coil temperature just above the freezing point of water. This is done to keep the evaporator from icing up.

The "on" cycle durations vary with different conditions but short "on" durations of just a second or two usually mean that the refrigerant charge is low.

 

Which I pressume would most likely point to a leak in the system?

 

My clutch keeps clicking on and off without the A/C running. Should I have it checked and recharged?

 

The compressor is allowed to operate in more modes than just the A/C modes.

AC compressor operation allowed:
Max AC
AC
Vent/Floor
Floor/Defrost
Defrost

AC compressor operation not allowed:
Vent only
Floor only
Off

Recharging it will not change the above. If desired, it is not difficult to add a dash switch to disable compressor operation. Just remember that the compressor should be operated on a regular basis, even in cool weather, to keep the seals and internal compressor components properly lubricated.

 

IIRC, when you go to MAX A/C the compressor will only kick on when it needs to cool down the recycled interior air

 

The amount of time that the A/C compressor clutch is on or off is determined only by the A/C Cycling pressure switch - it is preset to keep the evaporator coil fin temperature above the freezing point of water (an evaporator coil coated with ice is extremely inefficient).

That means that the compressor clutch can cycle on and off in any position of the mode selector that commands compressor operation.

There is no thermostat in the Ranger A/C system and the A/C system does not cycle to maintain any particular temperature in the interior, regardless of mode. A comfortable interior temperature can be maintained by modulating the HVAC blower speed and/or by running the heater against the A/C.

 

ahhh! See, you do learn something new everyday! Thanks!