Keith a/c unit

[NewMoon]

Has anyone installed this unit or a competitor in the recent past? 

How do they work? Cost installed? Time frame?

[LANCECASPER]

5 hours ago, NewMoon said:

Has anyone installed this unit or a competitor in the recent past? 

How do they work? Cost installed? Time frame?

I've seen a Keith unit in a Cessna yers ago, but they were never STC'd for a Mooney. Keith went through a lot of ownership changes, not even sure if they are made anymore.

I used a portable A/C in the Bravo I had that's discussed partway through this thread: 

 

[1980Mooney]

Keith was acquired by Meggitt (Addison Tx) and not to be confused with Meggitt PLC UK in 2006

Meggitt (Addison, Tx) was acquired by Air Comm Corp (Colorado) in 2013

Air Comm Corp today only seems to only advertise air conditioning systems for rotorcraft on their website.   They do show Support for A/C on Cessna 182, 206, Twins, and Citations, also Cirrus, also Piper Navajo. 

No Mooney

ACC | Air Comm Corporation

The competing Kelly (lighter by 26 lbs) draws 50 amps max at 28 volts.  

Aircraft Air Conditioning Archives - Kelly Aero

 

[A64Pilot]

My God, 50 amps at 28V? Surely that’s locked rotor amps, that can’t be running amps?

Actually as I think about it to get a decent output it would likely take that kind of power draw, but can any alternator make that continuously and run the airplane?

That’s 1400 Watts, who has an alternator that can make that kind of power? I’m nearly certain that if you did that a single belt couldn’t hold that kind of power.

AC we had on the Thrush pulled 100 AMPS at 28V, but we had a 250 Amp starter generator on the PT6’s and a 400 Amp on the Garrets.

https://zeesystemsinc.com/air-conditioning/

[1980Mooney]

3 hours ago, A64Pilot said:

My God, 50 amps at 28V? Surely that’s locked rotor amps, that can’t be running amps?

Actually as I think about it to get a decent output it would likely take that kind of power draw, but can any alternator make that continuously and run the airplane?

That’s 1400 Watts, who has an alternator that can make that kind of power? I’m nearly certain that if you did that a single belt couldn’t hold that kind of power.

AC we had on the Thrush pulled 100 AMPS at 28V, but we had a 250 Amp starter generator on the PT6’s and a 400 Amp on the Garrets.

https://zeesystemsinc.com/air-conditioning/

They say 45 Amps continuous operation (50 amps peak). That’s about 1,260 watts continuous. They claim it provides 12,000 BTU/Hour cooling. 
 

If you go to Home Depot and look at the portable 120 volt air conditioners that have a DOE rating (real vs marketing hype) of 12,000 BTU/Hr you will see that they also use the same or more watts.
 

So not a big surprise. Electric air conditioning is a huge draw for the limited electrical systems on most planes. 

[A64Pilot]

Yes but, there is always a but.

Spend more money and you can get quite a bit more efficient than a Home Depot window unit, more cooling / less power

Tesla’s heat pump has pushed that about as far as possible I think, but I can’t find info on its power draw anywhere

After I gave it some thought I realized the AC in a single cockpit Ag plane pulls 100 Amps at 28V, now they of course stay down in the heat, but this 100 Amp AC isn’t excessive, you don’t ever turn it off, and that’s a single cockpit airplane, no insulation though and pretty much no roof, but still it never gets as cool as a car can.

So after some thought I don’t think a “real” electric AC in a single engine GA airplane is possible, best you can get I think is nice cool air blowing on you but it’s never getting like a car where you can set it at 70 and really get the interior to 70? There just isn’t enough available power.

I’ve contemplated one a few times under the theory of running it for an hour in the hangar and getting temps down before going flying, but haven’t done it, and if you need 50 amps at 28V, that’s 100 amps at 14V, and That's just not possible

[A64Pilot]

Seems there is some more data now on the Tesla heat pump, appears amp draw is usually around 3 to 4 KW on a hot day and it can pull 7.5 KW max. That 3 to 4 KW was the car sitting still facing into the sun, sitting matters as Tesla cools the motor with the heat pump.

 I’m going to guess an automobile needs at least 3 KW of cooling to shed the heat load of sitting in the sun to cool down. And a Mooney is comparable to a small car, and I don’t see us getting 3 KW from alternator(s)