A/C Temperature Gauge?

[Mike G.]

Is there a temperature sensor for the A/C? The question comes not from a
problem but just interest in how the system works. If I put the fan on high
with the A/C on the coldest setting does it cycle on and off more frequently
from the additional heat added to the system or will it cycle on and off
just as often if the fan is on low?

Thanks,

Mike

 

[hbarta]

Is there a temperature sensor for the A/C? The question comes not from a
problem but just interest in how the system works. If I put the fan on high
with the A/C on the coldest setting does it cycle on and off more frequently
from the additional heat added to the system or will it cycle on and off
just as often if the fan is on low?

There is a sensor of some sort. The systems I'm familiar with (VW,
circa 1975) have an expansion valve with a 'pig tail' that stuck in to
the evporator (the heat exchanger that cools inside air.) The job of
the expansion valve was to control temperature in the evaporator so
that it did not go below freezing and plug with ice. The 'pig tail'
was a sealed tube that contained refrigerant (?) and it controlled
the expansion valve - a needle valve - through a bellows.

An air temperature valve cycled the compressor on and off to maintain
cold air.

I don't know how much the systems have changed since, but I suspect
they may be a bit more involved these days.