put the condenser for defrost mode inside the car.

[QueenBee]

Miss Piggy misunderstands. I'm not arguing that the condenser placement would be a problem, I'm saying that moisture will build up in the cabin in Winter in *either* case, if fresh air is excluded.

I presume by fresh air you mean outside air. So your argument is that excluding outside air will cause the drain tube to freeze and moisture to build up? Not sure how outside air is going to keep the drain tube from freezing.

In any case I have no idea how whatever point you are poorly attempting to make has anything to do with the OPs idea.

[johnrhansen]

Lb I agree with you. Fresh air should continue to enter the car as it does now. Just run it across the condenser first. I was thinking about it again, and I think the easiest way to do it is leave the condenser outside the car drawing cold air, but draw it from up high away from road moisture. Make it a sealed unit so that its exhaust air could go into the fresh air port in the winter, and rejected outside during the summer. The freah air intake is also selectable. The condenser outlet in the winter, and a second fresh air port in the summer. Then your head pressures and compressor load is not changed either. The only difference is the resistance heater isn't drawing as much power to replace the heat lost over the evaporator coils.

[Nubo]

Miss Piggy misunderstands. I'm not arguing that the condenser placement would be a problem, I'm saying that moisture will build up in the cabin in Winter in *either* case, if fresh air is excluded.

This was not proposed. As I understood it, "recirculates cabin air through both the condenser and the evaporator" in the OP, was simply referring to the condenser and evaporator being in the same airspace. It wasn't necessarily a proposal to exclude outside air (a.k.a. "recirculate mode"). Condenser placement and recirculate mode aren't mutually exclusive.

[Levenkay]

In my simplistic view, the only thing wrong with the cabin air (neglecting oxygen depletion) is the buildup of exhaled moisture. If you mechanically remove that moisture (by running the cabin air over a cooling "expansion" coil, allow the condensed water to run off & exit the cabin, then heat the dried air back up again by allowing it to run over the heating "compression" coils, how is that not better, energy-wise, than having to constantly heat a steady flow of cold external air up to the desired cabin temperature?

[dsny]

What about a cheap portable 120vac plug-in or battery-operated air conditioning unit, or heat pump?

Or speaking of exhaled breath: what about a full body suit to trap body moisture? This would be in the style of the stillsuit of course (i.e., full body suits that hydrate for life on Dune, a desert planet). This has been invented, right?

Would not bring up the Dune suit except that of course this is the kind of tech. that you expect to be showing up nowadays. Something like... [fumbles around in the couch pillows]... the Subzero Warm Breath Mask?

[BrockWI]

Basically moving everything "inside" would be like running a traditional dehumidifier. I wonder how well it could keep up with the humidity in the air.

Got me to thinking of throwing a 120vac dehumidifier in the back with a 2kw inverter and a big 8D battery to find out

[dsny]

Basically moving everything "inside" would be like running a traditional dehumidifier. I wonder how well it could keep up with the humidity in the air.

Got me to thinking of throwing a 120vac dehumidifier in the back with a 2kw inverter and a big 8D battery to find out

Yes. About the dehumidifier though. It seems the "operating temperature" of dehumidifiers is typically somewhat limited. E.g this dehumidifer:

"Temperature operating range: 5 - 32 °C"

https://www.amazon.co.uk/dp/B0026P6OMA/

Is this true? Will the dehumidifier pull out water below 5C? Or is it that in situations where it is below 0C outside the cabin would get above 5C quickly enough through the heater use?

[jkwilborn]

It's always interesting to note how some people always come up with ways that would hurt operation in other areas. Of course living in the SW Deserts we commonly hit 80 deg and above at end of March or at least by April and we start seeing 100 deg weather that lasts until beginning of October. Even the winters here are very mild compared to many parts of the country.

[Younio]

Guys, I think Tesla read this thread as they did just that witht their octovalve heatpump
[youtube]https://youtu.be/rgmBpEQtJ1s[/youtube]