converting OTR a/c to 134

[dj]

hey everyone its me again....any inputs on converting the OTR a/c system to 134?

[Geoff]

Do you want instructions?

--Geoff

[luvrbus]

It is going to cost you some big $$$$$$ to do it BTDT it is nothing like changing a car over where you change the oil,add fitting and Freon 

[buswarrior]

MCI had a complete technical bulletin detailing the "proper" methods, back when this was a big deal and R12 was scrapped.

Way down the road now, many AC techs kept wondering if it was all really necessary...

The oil and the gas and a new drier, yes... the o-rings and seals were the ones that some wondered if it really mattered.

FWIW?

happy coaching!
buswarrior

[luvrbus]

LOL you need to call Carrier with the compressor model number to you may get a big surprise like a $5G surprise 

[Geoff]

If you are using R-22 there is "eco-friendly" on eBay that is environmently friendly, 1:2.5 ratio stronger, and cheaper than R-22.

--Geoff

[J_E]

If it's R-22, as mentioned there is an alternative.  Typically referred to as MO99, it's R-438A.  It's comparable to R-22, but a little less costly and is supposed to be a fairly easy process to replace R-22.   Without a license, R-22 will run $70-100 per lb for residential AC service, not sure what it would run at a shop.

[Hi yo silver]

I had good results and performance with Freeze 12. ThermoKing proved to be a helpful vendor.

[Boomer]

If you have been running R-12 you can get by with good results with Freeze 12. It is a direct changeover.  If you want to change to 134 it will cost you.  Compressor oil change (3 times), change all hoses, filter drier and around 30 lbs. of refrigerant.  Plus labor of course.  Back in the day we ran a fleet of
MC-9's in a climate that ranged from 0F to 110F, some with O5G compressors, some with 5F30 compressors.  The 5F30's with Freeze 12 outperformed the O5G's on R-134. Maintenance was crucial, especially cleaning the condensers.

[daddysgirl]

If you have been running R-12 you can get by with good results with Freeze 12. It is a direct changeover.  If you want to change to 134 it will cost you.  Compressor oil change (3 times), change all hoses, filter drier and around 30 lbs. of refrigerant.  Plus labor of course.  Back in the day we ran a fleet of
MC-9's in a climate that ranged from 0F to 110F, some with O5G compressors, some with 5F30 compressors.  The 5F30's with Freeze 12 outperformed the O5G's on R-134. Maintenance was crucial, especially cleaning the condensers.

We did just the opposite back in 2006. The 5F30 was dead. Dad had a new 05G. However, we had to change the compressor mount. adjustment bar, high side line, discharge valve, suction valve, drier, etc.. It runs R-134 and will freeze everyone in the bus except me (but that's a windshield tint adjustment issue).
It takes 24lbs from empty, and thankfully dad had the equipment so I can check and charge it at home. But I could not agree more with your point on maintenance. I have a strongly held belief that maintenance is critical for everything. Every. Single. Thing.