Dual evaporators

[Cropduster]

First time on forum. I’m having trouble cooling the cockpit of a crop duster. We have a Sandin 508 compressor, a dual core 32,000 btu condenser with a pusher and puller fans, and an under dash evaporator. It works fine until temp gets up over 90 and then it’s just tolerable. My question is can I run a second evaporator under the seat by teeing off of the #6 line coming from the drier?

[bohica2xo]

Yep, no different than running dual evaporators in a Suburban with rear A/C.

Does your current evaporator use a TXV or an orifice tube?

What is the compressor RPM at flying speeds?

[Cropduster]

It uses expansion valve. Not sure of compressor RPM. It’s powered by a 3 hp 24 volt motor.

[bohica2xo]

Well then you just have to hope you have enough refrigerant mass flow. Electric motor / refrigeration compressor systems in aircraft are their own special snake pit...

We did this just about a year ago:

https://autoacforum.com/viewtopic.php?f ... t=aircraft