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Topic: How many pounds of freon (Read 944 times) previous topic - next topic

How many pounds of freon

Does any one know how many pounds of freon does it take to fill dash AC on a 2003 u320
Ac guy is asking me

Re: How many pounds of freon

Reply #1 –
I recently did our 1998 U320.  I added until the system reached proper pressure for the  outside temperature.  I had to swap gauge sets in the process, so my count is probably not accurate.

Irrelevant unless the system is evacuated.
Matt B
1998 u-320

Re: How many pounds of freon

Reply #2 –
Put a thermometer in the dash register and get it to 40 deg. at high idle is what I did. Pressures don't match for automobiles on my coach.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: How many pounds of freon

Reply #3 –
Quote from: craneman –
Put a thermometer in the dash register and get it to 40 deg. at high idle is what I did. Pressures don't match for automobiles on my coach.

Yup, just bought a bunch of cans, started putting them in, till dash was cold at around 40 FH. Actually as a FT tech, that is how we charged them. I have gauges, but for R12. Don't have adapters.

One can watch the drier window, and watch for slight bubbles in the glass (opposite of R12, where you watch for a clear glass, no bubbles.). But the drier is petty hard to see.

Also, you can feel the cold and heat in the 2 lines at the compressor.
I added 2 cans last year, and my system cools great now
Chris
Chris and Tammy White  CDA Idaho
Previous owners 1997 U295 36' 3126 Cat 300 HP Build # 4998
Former Foretravel tech & RVIA certified tech
Former owner Custom Satellite home/RV satellites 
Former owner Vans LTD  van conversions
Unemployed, panhandler, drag racer NHRA #6348

Re: How many pounds of freon

Reply #4 –
Did a evac, blew out the old oil, added new oil and my u320 took close to 5 lbs to reach full performance. If you're using cans, watch the oz measure, some cans are not a full pound and no more that 2 cans with leak detector, the rest pure freon.
🤯

Re: How many pounds of freon

Reply #5 –
I would really recommend changing the receiver dryer. Last couple coaches I did both had corrosion inside the dryer. I can't tell you why but preventative maintenance never hurts

Parker 3520-016 Receiver dryer

Scott

Re: How many pounds of freon

Reply #6 –
Quote from: dsd –
I would really recommend changing the receiver dryer. Last couple coaches I did both had corrosion inside the dryer. I can't tell you why but preventative maintenance never hurts

Parker 3520-016 Receiver dryer

Scott

  ^.^d  ^.^d  Anytime an AC system is open to the elements its a good practice to replace the receiver dyer / Accumulator. This device is the filter of the system, not to include many also carry a dessicant element to capture stray moisture which is detrimental to any ac system.

As for proper system charge, as long as the suction line is cold to the touch at idle,  your safe. I have built several auto systems from scratch over the past 30+ years and never had one fail or have issues as long as the suction line is cold at idle. Any good tech that knows ac systems, is familiar with suction side pressures and temperatures....personally I have not paid anyone to do ac work for me since I was a teen as I was taught by an ASE master tech at the time. If I were paying someone to do so, I would avoid anyone that all they ask is what is its capacity. Their is WAY more to doing an ac system properly than just the capacity.
Mike in AL
2001 U295
8.3 ISC 350
Build 5918

Re: How many pounds of freon

Reply #7 –
While we were making a visit to Scott's (DSD) home, air conditioner had never worked right and had thrown money at it to no avail.  We checked the system out and I ordered a new condenser fan, dryer and up in the dash, a valve that I can't remember the name of and I ordered a new A/C compressor.  Yes, dollars spent, but know it was done right!  Scott evacuated the system and to my recollection, put in 17 lbs of freon.  We now have an A/C with cold air.  Thanks to Scott and his experience, we are now happy cool campers going down the road!
Joe & Dottie Allen
Sold!  December 2023.      2000 U320; build # 5645
Our coach " Maxine"
Motorcade #  15922;  Escapee 150950; FMCA F330833; Boondockers Welcome;  Harvest Hosts;  Thousand Trails
'98 U320 from 2000-'06
USAF '62-'66

"Do not spoil what you have by desiring what you have not; remember that what you now have was once among the things you only hoped for." ―Epicurus

Re: How many pounds of freon

Reply #8 –
Quote from: juicesqueezer –
While we were making a visit to Scott's (DSD) home, air conditioner had never worked right and had thrown money at it to no avail.  We checked the system out and I ordered a new condenser fan, dryer and up in the dash, a valve that I can't remember the name of and I ordered a new A/C compressor.  Yes, dollars spent, but know it was done right!  Scott evacuated the system and to my recollection, put in 17 lbs of freon.  We now have an A/C with cold air.  Thanks to Scott and his experience, we are now happy cool campers going down the road!
Reciever dryer, like 17 pounds of flush,  compressor and oil, and about 5-7 lbs of freon, I dont remember. Charged to peak cooling temperature. You will need to have the freon recovered sometime and the receiver dryer replaced again. Also on your dryer has a visible desiccant viewing window. If it's pink again time to do it again. Blue okay.  Generally receiver dryers dont have that option, but the link I supplied earlier does. Very nice add on.
Scott

Re: How many pounds of freon

Reply #10 –
Quote from: WS6_Keith –
What fan did you buy Joe?  Was it a direct replacement?
I have an exact same fan as we installed on joes coach at the house if you are in vegas. Actually I have two
16 INCH ULTRA ELECTRIC 165 WATT COOLING FAN FFD16-3000CFM UPTO 25MPH WIND SPEEDS
Wasn't big enough for my Bronco Pulling thru too deep of stacked radiators. Engine radiator3" condenser 1", engine oil cooler and trans oil cooler

Re: How many pounds of freon

Reply #11 –
134a Replacement - Enviro-Safe Products

i used 3 cans of this r-134 replacement. It was freezing me out yesterday on the way home. I've used this product before and it has worked great. They are near Peoria, IL if anyone wants to stop into the store, but they also ship.
1991 U300 Side Aisle 6V92 Silver #3897
2004 U320 40' #6246