3 ms·
> There are other problems with an oversized system as well (Not an expert but I've dealt with HVAC enough) Short cycling is another problem. The system cools
by MisterTea 4y ago
> There are other problems with an oversized system as well
(Not an expert but I've dealt with HVAC enough) Short cycling is another problem. The system cools the room air faster than the air can absorb heat from the objects in the room and the structure itself. This causes the thermostat to cut out prematurely. The air then quickly warms from absorbing heat causing the thermostat to cycle on. The room again cools too fast and thermostat cuts off. That constant on-off cycling can damage the refrigeration compressor. Plus like you said, the humidity is not controlled so the room is cool and humid which is much less comfortable (to me at least.)
- criddell 4y agoWouldn't variable speed systems alleviate some of the issues with short cycling? It seems like this is something that automation could help. A variable speed system could learn what the neutral setting is for different indoor-outdoor temperature gradients and cool the space slowly enough to avoid short cycling. But then I dropped out of thermodynamics when I was in school, so I really have no idea what I'm talking about. Edit: After looking, I think everything is already in place. Our thermostat also measures humidity, so there's no reason it would run the A/C at a level that would make condensation a problem.
- lfowles 4y agoOne note I remember from my research, variable speed systems are tightly coupled to the thermostat so you may not be able to use an easily automated thermostat. My thermostat shows humidity (Mitsubishi MHK2), but as far as I can tell that doesn't factor into when/how hard the AC runs.