BeechTalk - BT

Username Protected · **Posted:** 10 Aug 2016, 11:16

Has anyone done the Steinbach and Associates "ConversionAir" conversion to R134a? We are looking at the kit for the Navajo.

What has the experience been? Does the system blow colder air than the last time it was working on R12? Reliable?

I know the benefits of MX and servicing by switching to this kit. Just wondering about the cooling capacity.

Thanks!

Username Protected · **Posted:** 13 Aug 2016, 08:58

No one?

Parts ordered and arrived. The conversion begins in earnest on Monday. Will report back on the outcome.

Username Protected · **Posted:** 13 Aug 2016, 09:38

Run vacuum on the system with a pump for a day, 2 is better. Deep vacuum will draw moisture out.
We used a A/C System Guru on the Cheyenne II 10-12 years ago. He greatly improved the system and sealed up a couple leaky points.
If your system wasn't working efficiently before with R-12 it might have issues that will still be there just converting to the 134.

Username Protected · **Posted:** 13 Aug 2016, 16:44

Username Protected wrote:

Run vacuum on the system with a pump for a day, 2 is better. Deep vacuum will draw moisture out.
We used a A/C System Guru on the Cheyenne II 10-12 years ago. He greatly improved the system and sealed up a couple leaky points.
If your system wasn't working efficiently before with R-12 it might have issues that will still be there just converting to the 134.

Cleaning the evaporator and condenser coils can also give a big boost in performance.

Username Protected · **Posted:** 14 Aug 2016, 04:44

Username Protected wrote:

Run vacuum on the system with a pump for a day, 2 is better. Deep vacuum will draw moisture out.
We used a A/C System Guru on the Cheyenne II 10-12 years ago. He greatly improved the system and sealed up a couple leaky points.
If your system wasn't working efficiently before with R-12 it might have issues that will still be there just converting to the 134.

Cleaning the evaporator and condenser coils can also give a big boost in performance.

Username Protected · **Posted:** 14 Aug 2016, 04:45

Username Protected wrote:

Run vacuum on the system with a pump for a day, 2 is better. Deep vacuum will draw moisture out.
We used a A/C System Guru on the Cheyenne II 10-12 years ago. He greatly improved the system and sealed up a couple leaky points.
If your system wasn't working efficiently before with R-12 it might have issues that will still be there just converting to the 134.

Yeah...I will talk to the guys about this. A huge advantage to the conversion is the ability to use our service cart.

Username Protected · **Posted:** 14 Aug 2016, 06:12

Username Protected wrote:

Externally or internally? I read that a good flush is necessary internally on both evaprators and the condenser. But I could see an external flush would be good also.

Internal flush is needed if you are converting from R-12 R-134a (or with any internal contamination), but an external cleaning of the coil fins is really important too.

A layer of dust on the coil fins can dramatically lower cooling performance.

There are special spray on coil cleaners (made to foam and safe for aluminum) but Simple Green Extreme is good too.

My A/C was just not as cool as it used to be even after evacuating and weighing in the right amount of refrigerant. Once I cleaned the coil fins it was better than ever.

Username Protected · **Posted:** 15 Aug 2016, 00:05

Username Protected wrote:

Externally or internally? I read that a good flush is necessary internally on both evaprators and the condenser. But I could see an external flush would be good also.

Internal flush is needed if you are converting from R-12 R-134a (or with any internal contamination), but an external cleaning of the coil fins is really important too.

A layer of dust on the coil fins can dramatically lower cooling performance.

There are special spray on coil cleaners (made to foam and safe for aluminum) but Simple Green Extreme is good too.

My A/C was just not as cool as it used to be even after evacuating and weighing in the right amount of refrigerant. Once I cleaned the coil fins it was better than ever.

Username Protected · **Posted:** 18 Aug 2016, 19:12

Conversion done. Kit is pretty straight forward. Lots of time needed to do everything. Blows 55 degree air now. But Piper's way of moving the air from the evaprators to the vents is horseshit. Typical of a plane designed in the 60s. Next time it needs interior, there must be a better way.

Will fly the plane Sunday and Monday, so will report back.

As a side note, flew a PA34-220T with G600, 530w and 430w. Pretty slick set up! I have a lot of G1000 time, but give this the edge. For flexibility. GPSS interface to older KAP150 worked great.

Username Protected · **Posted:** 21 Aug 2016, 17:39

Short flight today, but hot here. Definitely was cooling down the cabin on the ground and one hop around the pattern was very comfortable. It doesn't blow freezing cold air like a car, but I think that has more to do with the crappy ducting and evaporator box than anything.

Multiple cans of cleaner to get the evaprators and condensers clean inside. Evaprators got a soak in water and comb job. Lots of dirt and hair on the outsides.

Biggest thing to me, is we now have a "modern" system that can be easily serviced. Beats trying to find black market freon.

A hot day tomorrow (90s), so it will get a workout.

CB

Username Protected · **Posted:** 21 Aug 2016, 19:17

When we had the Cheyenne II the book said the A/C would cool 20 F below outside temp max on a good day. Would've been written when it was new so 25 years later best was probably 15 cooler than outside.
Glad its working better for you.