Ford F150 - Climate Control - does the compressor stay on in all modes?

1997 F150 v6. It seems the compessor is on in every districbution mode: Both AC & AC Max (normal), Vent, Panel & Floor, Floor, Defrost (normal). From my experience with other systems, the compessor is only active when in AC or defost mode. The manual I have does not directly say, but seems to indicate the compessor is on in all modes of districbutiion. Under tips it says: Drive with climate control system on ( in either the heating or air conditioning mode) to reduce humidity in your vehical. I would imageine to reduce hunidity the compessor must be on. Any ideas what is normal for this vehical.

If this is not normal, what is the likely cause of the compessor staying on. The compessor does turn off when the heating and cooling switch is turned off. I can definately feel the compessor kick in when driving slow in gear.

The compressor is supposed to operate in all positions except 'Panel', 'Floor' and 'Off'.

As the manuals states, air conditioning is more than an air cooling system. It also removes humidity by directing incoming air over the cooling coils first (to condense the humidity out) and then through the heater core to warm it up again. This allows you to dry the air without changing the temperature...

Another advantage to having the compressor run in non A/C positions is that it circulates compressor oil to keep the seals from drying out.

When the temperature drops below 50F (10C) the compressor has no effect.

Thank for replying.
When the temperature drops below 50F (10C) the compressor has no effect.What happens below 50F? Does the compressor turn off? I thought the AC would drop the temp approximately 40 degrees from whatever temperature was coming across the coil.

Today on the way home from work, I tried the different modes of operations and they worked as you said. Thank You.

I have two Ford vehicles and both owner's manuals say the A/C has no effect at around 50 degrees and lower. I don't know for sure, but I'm guessing the cold causes the operating pressures in the system drop to a point where the low pressure switch cuts off the compressor so it just cycles now and then. (A/C operating pressures go up as the outside temperature increases and they go down when the outside temperature decreases).

Perhaps there's an A/C tech who can answer for sure?

Thanks. My main concern was being able to run the outside air without the compessor on all the time. Now that I know how the switching settings work, I am good to go.

Fresh air with A/C is called "NORM"; recirc with A/C is "MAX" (the most fuel-efficient A/C mode); fresh w/o A/C is VENT or FLOOR.