New Gradient window inverter heat pump.

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Brian26

Minister of Fire
Sep 20, 2013
694
Branford, CT
Looks a lot like the Midea design but this one claims it will also provide heat. It supposedly operates just like a split system.

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Looks like minisplit with different packaging. No reason it can not put out heat, its just needs reversing valves and variable speed cold climate compressor if its in cold climate.
 
Wouldn't even need a reversing valve if the build it so you could just pick the unit up and flip it around in the window! Air conditioner on the inside, blowing hot air out the window - as shown above. Or flip it around, with the box outside, and the small duct blowing hot air inside for 'heat pump'.

Though, around here, that would mean about two months of constant flipping back and forth! It would also make more sense if the 'box' was the heat pump portion - that way you'd have all your compressors, fans, etc on the inside of the house - making even more heat. Then when it was time for cooling, the 'box' would be on the outside - taking all the heat with it and only blowing cool air in, kind of like... well, a standard window air conditioner.

Also would be curious how they handle condenser coil air. That is one thing that is always terrible about 'portable' air conditioners...they take a good portion of your cool room air to blow over the condenser, then that hot air gets blown outside. There would be ideal ways to handle it, but seeing "San Francisco based start-up...." tells me all I need to know!
 
Okay you win ;) I imagine all the apartment dwellers rotating their units and then suing when they inevitably drop them down to the sidewalk. Most of the noisy stuff is best kept outdoors including the condenser coil so I think I would vote for a reversing valve.
 
Okay you win ;) I imagine all the apartment dwellers rotating their units and then suing when they inevitably drop them down to the sidewalk. Most of the noisy stuff is best kept outdoors including the condenser coil so I think I would vote for a reversing valve.
And then there is the condensate issue.
 
Most of those indoor units have sump and pump and have to discharge to a drain.
 
Most if not all window units have a gravity drain outdoors from the back of the unit. I am curious if a pump will be used. That is another point of failure and clogging, especially due to accumulated dust.
 
Okay you win ;) I imagine all the apartment dwellers rotating their units and then suing when they inevitably drop them down to the sidewalk. Most of the noisy stuff is best kept outdoors including the condenser coil so I think I would vote for a reversing valve.

True - I forgot that you can't expect anyone to be responsible anymore! :oops:

Condensate handling is interesting. Some of the newer window AC's I have encountered actually catch the condensate in a trough and use it as a 'pre-cooling' step for the hot gas coming out of the compressor. (Well, actually, my 1973 Whirlpool central AC did that too... so maybe this is 'lost' technology?)

Makes sense - you have a source of cold water, why waste that potential by letting it drip on the ground. Ideally, you could put that condensate to full use by completely evaporating it, then you'd capture not only the 'cold' of the condensate, but latent heat of vaporization of the water, too. So if done properly, you wouldn't even need a pump - you'd just have warm/humid air discharging off the condenser coils.
 
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Most if not all window units have a gravity drain outdoors from the back of the unit.
I was reading a the manual on a new regular unit. Said noise of water hitting metal was ok. Next sentence was if you pulled the plug out of the shallow drain pan efficiency would go down. So I assume they are flinging water from the pan on the outdoor tube or coil with a fan.

Why don’t mini splits use the condensation?

Evan