Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: nitehawk on May 12, 2017, 09:01:20 am

Title: 1989 GV Dash Air Freon Capacity
Post by: nitehawk on May 12, 2017, 09:01:20 am
I realize I am reaching out there when I ask what the freon capacity is for a 1989 GV Dash AC but I cannot find the info anywhere. So I am hoping someone here knows.
Title: Re: 1989 GV Dash Air Freon Capacity
Post by: stump on May 12, 2017, 09:12:00 am
Are You still R-12? or has it been converted to 134a?
Title: Re: 1989 GV Dash Air Freon Capacity
Post by: craneman on May 12, 2017, 09:14:14 am
You really don't need that information to get the system up and running. I tried the volume method with the information from Beam Alarm and my pressures seemed off. Put a thermometer in the dash register and charged until I had sweat at the compressor on the low side, then fine tuned to get the coldest air. The thermostat shuts my compressor off at 40 deg. at the dash.
Title: Re: 1989 GV Dash Air Freon Capacity
Post by: craneman on May 12, 2017, 09:20:20 am
Are You still R-12? or has it been converted to 134a?
I didn't ask that question. Hope it has been converted otherwise price prohibitive on r-12. It can be converted but the method I posted was for r-134a To convert from r-12 to r-134a the refrigerant oil has to be changed and 80% of the amount of r-12 used put in with r-134a. Which brings it back to needing the factory volume to do it without having to do trial and error on the charge.
 I believe it was around 1994 r134a was required in cars.
Title: Re: 1989 GV Dash Air Freon Capacity
Post by: kenhat on May 12, 2017, 09:25:35 am
Nighthawk,

I had a receipt from Oregon Motor Coach where they drained the freon (4 ounces) and refilled with 6.5lb. I used that figure when I changed out my compressor. About 10 cans. That seemed like a lot but there is about 80ft of hose back and forth to the compressor . It was too much. Had to drain out quite a bit then added a little before it would cool. I have to give a shout out to master technician Dave Katsuki for help in getting it going.

I agree with @craneman just add till the dash temp starts falling. It takes longer but it works.

Edit: I'd start with 4 or 5 cans then start keeping an eye on the dash temp.

see ya
ken
Title: Re: 1989 GV Dash Air Freon Capacity
Post by: stump on May 12, 2017, 09:55:44 am
I have a 100# tank of R-12 But I'm still going to convert over to 134a just because it is readily available.
Speaking of refrigerant. R-22 which is probably in your house has gone up wholesale to about 600.00 for a 30# jug. Which is going to make servicing home units prohibitive requiring a system upgrade to R410a.
Title: Re: 1989 GV Dash Air Freon Capacity
Post by: craneman on May 12, 2017, 10:15:11 am
Stump, 100#!!!
I thought I was the only hoarder. I bought the 12 oz. cans for 50 cents back in the 60's then bought 30# bottles and never used the cans.
Title: Re: 1989 GV Dash Air Freon Capacity
Post by: nitehawk on May 12, 2017, 12:29:30 pm
Sorry you guys with the R-12 stash/hoard/potential goldmine. My coach and Triple nickle's coach have both been converted to R-134A
But thanks for the information.
Title: Re: 1989 GV Dash Air Freon Capacity
Post by: craneman on May 12, 2017, 12:36:06 pm
Then my first reply is where to start. Ken's starting count would be a good start.
Title: Re: 1989 GV Dash Air Freon Capacity
Post by: Kemahjohn on May 12, 2017, 04:21:11 pm
I had a 1990 Grandvilla and was told by Foretravel that it required between 6-6.5 lbs of R-12 for full charge.  There are R-12 alternatives that work fine in the R-12 system that do not require system conversion.  Google R-12 replacement.  RedTech is the name that comes to mind.
If you call Foretravel they will give you the details on the charge required when using R-12.
Title: Re: 1989 GV Dash Air Freon Capacity
Post by: Kemahjohn on May 12, 2017, 04:24:20 pm
Here is a link to redtech R12a

RED TEK - 12a Refrigerant (http://www.redtek.com/win_12a_refintro.html)
Title: Re: 1989 GV Dash Air Freon Capacity
Post by: TexasPop on May 12, 2017, 11:05:17 pm
First, I want to thank everyone that supports this forum for all of their time and hard work.  You've been TREMENDOUS help in steering me to my first RV as I am now the proud owner of a "Baby" (2 month old to me) 1987 GV Oshkosh.

Hopefully this will help, my 40' was professionally converted in '99 to R-134a.  The sticker says to charge to 3 lbs. 0 oz.
Title: Re: 1989 GV Dash Air Freon Capacity
Post by: Protech Racing on May 14, 2017, 12:51:01 pm
 I put the gauge on one fitting and charge the other, engine off, to about 110#.  Then start it up and make sure the compressor turns.  Start reading the gauges and the vent temps , adding carefully .
Title: Re: 1989 GV Dash Air Freon Capacity
Post by: nitehawk on May 14, 2017, 01:23:50 pm
By the way, I opened the small access door up front, on the pass side, and there is a sticker on the Atwood AC/heater box that says 454 Chevrolet. And the dash controls are Ford. No wonder the darn system works so lousy!! They just can't agree!! >:D
Title: Re: 1989 GV Dash Air Freon Capacity
Post by: Kemahjohn on May 14, 2017, 03:21:20 pm
Yep, they used a big block Chevy system except for the compressor which is larger, and the Ford dash mounted goodies.