did a search on chassis ac recharge...only found old posts...need current info on recharging my breakaway system at home. What to use? How to do it? where to buy what I need? any suggestions for do-it-yourself.

I assume you mean the engine/dash system. You no doubt have a R134a system; that refrigerant is readily available. The fittings are different for R134a than for R12 (different sizes, too.)

Recharging correctly requires a manifold and gages ($100-150); the "kits" at auto repair stores are inadequate for proper recharging. Typically, the Barth will take 2.75 lbs R134a.

Rule-of-thumb: Charge to ~30 psi suction pressure; the "kits" have a gage, but it's of questionable accuracy.

However, you may have issues other than loss of refrigerant; without the manifold (and knowledge), you can't tell what's wrong with he system. If there's a leak, that can be detected with UV dye in the refrigerant. A leak can deplete the compressor oil, which means a flush and refill.

Bottom line: If you don't understand refrigeration, get a qualified technician to check the system before you take on the maintenance yourself.

remove all old r-12 put need refrig in make sure to add die and put oil in first kits readily availabe over counter 30$ proabally with out leaks under 50 $

I have a '94 Breakaway and it has R12, I didn't do that conversion because the efficiency of R134 is not as good as the R12, the system only took right at 2 lbs.

I take mine to a qualified shop, I don't mess with it there are so many areas that can leak and cause trouble, I believe I'm better off to have some who knows what they are doing work on it.

System cooled OK in LV last week with temperatures over 100 most days.

I will assume no leaks, but over the years you have had seepage. Here is what I did on our '92 with R-12. If you have R-134 then things are simpler as it is available everywhere.

First for the legal. If your system has R12 the law requires a licensed tech to deal with it.

I bought a set of gauges available at Harbor Freight for about $50.

Next I orders a case of enviro-safe. This is a hydro-carbon product that will mix with either R12 or R134 and will use either oil.

If is not requered to evaculate the system, so now you simply fill the system. The low presure side will be 25-40 lbs and the high side about 150 or less.

Since the hydro-carbon molucules are larger than either R12 or R134 molucules seepage will be less than before.

One final thing. If you do not have a low pressure shut down, install one. They make one the simply screws on the low pressure fill.

good information...how do I tell if system now has R12 or R134? If I use the enviro-safe, sounds like it doesn't matter, but I would like to know anyway. Is the enviro-safe available at Canadian auto parts suppliers? thanks guys

Look at the charging nipples. R-12 will have screw on fittings while R-134A will have quick disconnect type (if they were converted properly). By law they had to be changed in the US, don't know about Canada. Now for the difference: You should evacuate all R-12 and then flush with appropriate stuff. The oil in the compressor used for R-12 is not compatible with R-134A - it coagulates and will block the expansion value and gum up the dryer. R-12 is taken down to about 15 to 25 lbs at optimum because it freezes at a lower point than R-134. So if you mix the two the R-134A will in liquid form when the R-12 is still a vapor. That will reduce your cooling and raise your high side pressures above optimum. R0134A requires ester oil and it should be in a clean system. Always change the receiver dryer when you change or open the system. It will normally come with the low pressure safety switch mentioned above. R-134A will take about 80% of the quantity of charge in you R-12 system so a 2 lb R-12 will be about 1-3/4 lbs of R-134A. When charging the system with R-134A it is best to use the 80% rule and then add only until the sight gauge shows no bubbles (system on MAX and engine at 1,000 to 1,200 rpm). Overcharging of R-134A is a bad thing as it reduces the expansion and condensing process efficiency and causes freeze up of the lines.
Most coach systems will not cool the unit because they are too small and don't move enough air. I replaced the condenser (at the engine) with a 40,000 BTU commercial unit made by FrigiKing for airport vans and that not only added a lot of capacity (6 lbs of R-134a), it lowered the high side pressure to reduce the load on the compressor. (It does cost about $750 though plus labor). Since I am in Texas and you are in BC it is probably overkill for you, unless you go to Arizona for the winter.

if u still want to go r-12 have acess to about a case

I have a 72 Chevy Nova that needs some R-12. Could I get 4lbs?

The hydro-carbon replacements were available in Canada before the USA. So just use google and you will find a number of mfgers up there.

Hi 98 Barth Monarch

I just had my Air checked/recharged. The guy said it took just over 3 lbs. He said the high and low reading were fine. The reason I took it was that it starts out blowing very cold and then after a while it warms up where there is no cold at all. However if I stop for a while the unit blows cold again.

I had a VW bug with air con, in Thailand, and had a slow leak. When the freon got a little low it started out cold but then as the system heated up it would only blow cool air.

In the case of the Barth the recharge did not help. I think the condenser/temp probe is freezing up. Could be mouse nest in the exchanger or some dirt causing the unit to freeze up. I think the access to the exchanger is via the entry way panels.

Tom

This sounds like the expansion valve. On that, there is a capillary tube that opens the valve when the evaporator is near freezing. The symptoms you describe fit that diagnosis quite well.

Cap tubes are constant metering of the refrigerant.

TXV's open and close to automatically control the flow of refrigerant. The bulb off the head controls the flow. As the line warms up, the needle valve opens to allow more refrigerant and as the line cools, it closes to reduce the flow.

I read up on this and indeed the problem is most likely the expansion valve. They state this happens when waster gets into the system. The system was evacuated then recharged, I think.

If the water was taken out then the system should be fine.

Tom

need ur address bill !