Portable A/C

rgatijnet1 wrote:

wwest wrote:

Sorry, you simply CANNOT exhaust living space airflow without it being replenished. Mother Nature, you know, HATES a vacuum.

If I were you, I would not get one.
Since I am me, and have several years of experience with my portable heat pump/AC unit, I think I will keep it. Nothing beats actual experience, which is why I got rid of my double hose unit and went with a single hose unit. :B

1.) In the 2 hose unit the incoming outside air, HOT air, passes through the CONDENSER in order to COOL the pressurized refrigerant within. A portion of that airflow bypasses he condenser and is used to cool the compressor. All of intake air, now heated, is then EXHAUSTED via the second hose. Yes, there is often 2 blower motors, but the gain in system efficiency easily overcomes any extra heat, if any, generated in the process.

Using a single blower means the blowers must run at the highest speed required of either. HOT outside, the condenser cooling blower MUST run at HIGH speed. This conflicts with the evaporator blower since the slower it runs the greater will be the cooling gain through the evaporator.

2.) As the linked article states:

A single hose A/C takes some of the cool air from the room and uses it to cool down the compressor(***1)..and then shoots it outside. Not only does this waste a significant proportion of the already-cooled air, it creates what is known as "negative pressure" in the room. In order to replace the air lost through the exhaust, warm air from adjacent rooms(***2) will seep in, which decreases the overall cooling efficiency.

***1. Typo.. should say condenser, compressor cooling is secondary. Condenser needs to remove ~10-12,000 BTU into that airflow, compressor heat represents maybe 300 BTU.

***2. And ultimately from the HOT atmosphere outside the home/RV.