"L.W. (ßill) Hughes III" wrote in message: We have swap coolers out here in
our deserts, but I can't imagine
how water could be used to cool a refrigerant, how it could be more
efficient than just a regular condenser cooled by air being blown through
it. Would it still use something like freon to take the heat out of the
building?'


Water is not the refrigerant. The water is used instead of air on the
condenser. Water is used in a lot of system that have a high heat load.
The water helps condense the refrigerant back into a liquid after it has
been compressed. The liquid refrigerant then passes through a metering
device (capillary tube, orifice, expansion valve) to feed the evaporator.
The air that passes over the evaporator transfers heat with the refrigerant.
This turns the freon back to a gas. It then gets compressed again and the
cycle starts over.

If water is used on the condenser, the water is either disposed or recycled
in a closed loop system. Water can come from the city supply and use to
supply water to your water heater. What not used is sent to the sewer,
drain or pumped into the ground. If ground water is used, water is pumped
to the condenser and back to the ground.

If the system is closed loop, the water is circulated from the condenser in
to a tower called a cooling water tower. Air then cools the water back off
and it is pumped back to system. Make up water is needed and the water must
be chemically treated to prevent algae and conductivity problems with the
metal. The cooling water tower usually has a fan that pulls air upward
while the water drains downward.

These type of system are used where they may be one unit supplying multiple
evaporators. This allows individual zones to be adjust their temperature
without affecting other zones. In order for the unit to run properly there
is probably a spill back line that is adjusted to allow minimum refrigerant
flow yet will close down when a load is needed, This is one problem area on
the units is the spill back valve. They can stick in one position thus
causing HVAC problems.

Sarge