British thermal unit: a unit of heat equal to the amount of heat required to raise one pound of water one degree Fahrenheit at one atmosphere

A BTU is a BTU. I guess a 12,000 BTU would cool more than an 8,000 BTU unit.

V

I know that a BTU is a BTU; however it depends on how efficiently those BTU's are being used. An 8,000 BTU Portable A/C will not cool the same area as effectively as an 8,000 BTU window unit.

A Portable A/C works differently than a window unit. A single hose Portable A/C uses the room air to recirculate which the condenser cools and blows back into the room, while the window unit pulls air from the outside, cools it and blows it into the room. Fresh outdoor air is a more efficient way for a condenser to cool and use air.

I am not sure if I am understanding. My window units do not bring in outside air and cool it. Rather it recirculates air from the room, drawing it in and around the chilled coils and then blowing it back out to the room. Always bringing in outside air to cool would be rather inefficient if the air was 95 degrees and you only had a 15 degree drop through the AC unit then the lowest you would get the room temperature is 80 degrees. However if you recirculate the air, then it gets progressively cooler.

The heat is wasted outside on the window unit.

I think the portable works similarly except it has to blow the waste heat out the hose from the back instead of just letting it be passively exchanged to the outdoor air.

aceh, have you been talking to my grandmother? :-)

A window unit does not work the way you described. For one thing, on any air conditioner, it's the evaporator that cools the room air, not the condenser. The condenser dumps the collected heat.

Have a look at

. The partition is shown partially cut away, but in actuality it extends across the width of the unit in front of the compressor to keep the indoor and outdoor airflow path separated. Room air is pulled by the blower through the filter and evaporator in front of the unit and blown back into the room. The separate outdoor fan pulls outdoor air into the grills on the outside of the unit's cabinet, and blows it through the condenser at the rear.

Some window units have a fresh air setting, which opens a small panel through which a very small amount of outdoor air is supposed to be brought into the room, but most of them don't have much effect.

Sorry for screwing up by passing on bad information. That's what I get for not checking out the facts for myself. Thanks for clearing this up for me.

However; isn't it true that an 8,000 BTU Portable A/C will NOT perform the same (i.e. cool the same area) as well as an 8,000 BTU window unit?