In article 0CZQb.121066$nt4.532531@attbi_s51,
Wood Butcher wrote:
A dehumidifier will add MORE heat than a electric resistance heater
with the same power consumption.

It's obvious that all watts consumed by the dehumidifier will stay in
the garage as heat. What is not so obvious is that when water vapor
condenses into a liquid it gives up heat (just the opposite of what
happens when it evaporates).

Yawp. *lots* of heat.

Approximately 970 BTUs _per_pound_ of water condensed. That's enough
heat to raise the temperature of 10 lbs of water by nearly 100 F.

Or, 8,200 BTUs per gallon of condensate.

For the metric crowd, 540 calories per gram. Enough to raise 10 grams
of water by 54 C.

There is also the heat pump effect of
removing heat energy from the cold condensate if it is piped down
a drain.

The effect of this is _trivial_ in comparison to the condensation.

If the water is at 20F below 'room temperature', that's a whopping
TWENTY BTUs per pound of water that goes down the drain. About 1/5
of 1% of the energy released by condensation. Hardly worth mentioning.


Art

"Fred the Red Shirt" wrote in message

A dehumidifier will also help to heat the garage, just as much as
any electric resistance heater with the same power consumption.