Safe to say she’s (literally) put out to pasture. She’s in one corner, another citation and a freighter falcon in others.

Just in time for summer. Optimized the a/c system. 50F drop from ambient. Hangar is at 78. The cabin was ice cold in 10 minutes. That’s a win!

That's too cold, it will ice up. Anything below freezing will do that.

It suggests your expansion valves are set too high which will make your compressor work really hard and wear out sooner.

Mike C.

Yes, I agree….but I doubt that evaporator is going to freeze in a heat soaked airplane with a cabin temp of 180F. It’s fine for now.

One thing at a time, Mike C. LOL

Ahhhh...actually Nishaunt, Mike is correct. You should be targeting a 30ish degree drop across the system.

We fixed a freon leak at the compressor, flushed the system, and replaced the receiver dryer all per the MM.

I think most of the instructions in the manuals for charging the system are outdated compared to what we know now. I'm not just looking for a high side and low side number. I also want to know high side and low side temps. I charged the system with enough freon to get a 10 degree subcool on the high side and an evaporator core temp of 34 F.

It's charged right and it works great. My goal was a 30F drop to ambient but I got way more. I'll take it!

Speaking of ac...I'm the not so proud owner of the world's ugliest evap cores.

Ace Thermal Systems have decreed that these are now proprietary Piaggio parts and refuse to sell me replacements.



Currently unravelling the Ace/AirComm/Meggitt/JB/Keith/EnviroSystems parts commonality and working on a solution.

You mean standing in the hellhole watching for bubbles in a sight glass isn't scientific enough for you?

Nothing a fin comb and some time can’t fix!

Chip-

So Ace never got PMA for your STC? Or was it someone else's STC that is now orphaned?

I've run into this in the past. Sometimes it takes a statement on your part that you will conform it for your STC.

There are parts shared between the old Keith/JB STC and the Piaggio STC.

Ace Thermal Systems refuse to acknowledge the older STC documents. Tarver told me that Ace are pretty much the worst company in aviation and I now understand what he means.

Probably a dumb question, but could you get a Piaggio owner/shop to do the purchase/exchange? IJSC in Tulsa may be able to help as they do both Citations and Piaggios.

Any chance these work for your application? They look like they are in good shape.

JBS275-5
https://baspartsales.com/jbs275-5-keith ... LEGTPMnDwm

JBS275-6
https://baspartsales.com/jbs275-6-keith ... KTJCEqoKnJ

My guy at Ace says they are waiting on PMA for their 501 STC. Maybe once they have that it'll be easier to get new parts, but I bet they'll be exceptionally expensive.

So likely yes to both in some fashion or another...but I'm not interested in beating them with money until they submit.