Quote:
Originally Posted by dremd
I've been thinking a lot about tube in tube heat exchanger construction, and realized the guys running plastic external tubes are doing heat only so their heat exchangers are COLD (duh). Mine would be hot, so I'd need copped at least on the hot side.
Maybe 10 feet copper-copper then the rest copper-PEX with a thermal cut off.
|
If you added to the existing condensor, you could run copper plus plastic with no worries of overheating anything. The existing condensor capacity would temper the hot gas and convert it to warm liquid. The coaxial exchanger would work in liquid-liquid exchange mode, cooling and subcooling the liquid line to very close to the well or bayou water temperature, effectively raising your SEER close to its maximum attainable value.
Quote:
Originally Posted by dremd
More thoughts, maybe what would be equally energy saving would be web connected thermostat (NEST at least looks pimp) such that the cooling could be switched to a lower setting several hours prior to arriving. I suppose either a contactor, or a solid state relay with a bit of re-wiring would make that happen. This would also have the benefit of getting the thermostat away from the A/C this making it much more accurate. Anybody have any experience doing such a "conversion" to a window unit?
|
If you can wire up a remote starter for a car alarm, you can control the window unit. Just replace the thermostat (if knob-type) with relay contacts or use transistors (if digital-type) to assume control of the compressor relay.
Quote:
Originally Posted by dremd
As another note, sorry for the terribly slow response, for some reason I didn't get a forum notification, I probably have this thread open in a browser window someplace.
|
The maximum energy efficiency you can get out of these units depends on many factors. The most important is your incoming water temperature. If the well source is much cooler than the bayou source, it would provide a better heat sink. The next most important factor is the metering device. A txv would match the evaporator load much better than the existing cap tube. Both of these factors add complexity and expense to the units. They may or may not end up paying for themselves quickly.
In contrast, air-sealing and well-insulating a leaky, uninsulated building will always pay themselves back many times over and over without any upgrade of your heating or cooling source. A small solar roof vent would do magic for this little house IMHO. Especially on a sunny summer holiday weekend.