It worked very well down to around 40 degF outside. I had the unit rigged to a waterbed thermostat in the aquarium. The unit would hold the tank at max temp (i think it was 90F) until it got cold enough outside to force defrost. As long as it was above freezing outside, the unit would defrost itself and start back up again.
The warm water spray defrost worked well, and got the unit working down into the 20's. With the fish tank as a heat store, it kept my sunroom and living room heated pretty well for a winter. It was a really huge learning experience for such a small rig.
The next season brought a need for cooling, so I retired that rig and found a 9000 btu portable ac unit on cl for cheap and began experimenting with it. I also began playing with window units. These trials eventually led me to build a window shaker heat pump that worked well down to near zero degF. It used a 15kbtu compressor originally made to go in an rv ceiling/roof unit.
I have now caught the bug and cannot help but hack together phase changing monsters. This stuff is amazing! I wish I would've learned about it when I was 10.
|