I just completed a trip from Houston to LA and then to INDY using only the dash air to cool the coach. What made this possible was my diesel mechanic shop inspected the system after I put a 40,000 BTU condenser in place of the 5,000 that was mounted under the engine compartment. The Barth approach was to run a mile of rubber ac lines and use the stainless steel screw clamps everywhere. He told me he had pressurized the system and it had no leaks after three days of sitting around and that the screw clamps always leak when vibration is added on the road. I had the system slowly leak down last fall while driving and just refilled it. Although it was expensive - they removed all the lines and put new crimp type OEM connections at every junction and after 6 thousand miles I still get 50 degree air at any outside temperature. I did have to remember to always turn on the rear fan motor or it would freeze up, but we had complete comfort and even had to turn down the fan on the dash after about 100 miles each morning. This may be of interest to those rebuilding or improving their systems. Avoid crew clamps on ac systems.
Tom

quote:

Originally posted by Tom K:
Avoid crew clamps on ac systems.
Tom

I wonder how the constant torque worm-drive screw clamps would do. I also avoid the regular screw clamps and use either an Oetiker or the constant torque clamps whenever possible.

Tom: do you still have the vintage air maxi cool system? I am already pretty annoyed with mine...(half the battle is I am letting mechannics figure this stuff out and it gets expensive). If you do, does this unit work for heat as well?

My coach has the Acme Auto system with two evaporators and fan assemblies. One in the dash and the second in the port side hallway at the rear bedroom. Both are heat or cool and in fact the fan switch that controls the aft system says Aux Heat, but it is only a fan. The temp is controlled by the dash slider to the front unit. If heat is needed in the rear then the aft propane furnace takes care of that. I have installed Vintage Air Maxi Cool systems, they are much more modern than what is in the Barth and they usually have heat-defrost and cool. The newer units are electrically controlled and do not need vacuum to operate the various flap motors that direct the air flow. Vintage also uses quick couplers and ships their units fully charged but after while they will slowly leak down. Depending on how difficult it is to reach all the connections a good shop will have a portable swage tool that allows hydraulic crimping at the work site. If you are experiencing loss of cooling and the hoses are installed with clamps then I would suspect them. For the test that was done on mine the mechanic charged the system with 300 psi of nitrogen and monitored pressure. After three days it was still at 300 so the clamps were the weak link. When the engine was running (with R-134a installed) the pressure began to drop about 2 psi each fifteen minutes. After replacement with swaged connections that problem went away. In you area ask the locals where they buy their ac hoses, compressors and tools. There is someone who is the wholesale supply and they know who has the equipment to fix your problems. If not check around and see if you can use a major city as a two day or so stop while on a trip and see if this type of service is available.

Tom,
I must say I am thoroughly impressed with your improvement and results from your dash air. I haven't had my coach a year yet and from previous coaches I've owned I haven't yet taken the time to even study my dash air (manuals). So far this HOT summer I've just ran the jenny and overheads. However we have similar coaches and have to ask you if you had the entire system gone through at some point. My coach is a little older and basically 20 years old now, I suspect if I wanted to tackle a project as you've done I'd first need to ensure my current system is solid. Mine has the GM style push buttons and slider control cold to hot. I see the rear fan control but haven't used it. Also I guess mine was set up for R-12 and hope it now has R134 in it.
I would really like any additional insight you could give on this upgrade for I live down in the heat as well; fortunately I'm at nearly 1900 ft ASL and we have little humidity.
BTW I grew up in League City, and we moved to Brady from Kemah in 2006.
Any additional data, such as how you sourced and sized the larger condenser coil would be appreciated.
Outstanding upgrade!

If you have a clear pathway to run tubing, I would replace most of the rubber hose with Type K copper tubing and rubber hose at vibration points(i.e. compressor) with the swaged fittings. Use high grade silver solder ~20% on the fittings. I agree hose clamps were never designed for high pressure air conditioning systems.

I like the idea of rigid tubing swaged to flexible (rubber etc) at the compressor. I just replumbed my entire 85 year old, 2 story house here in the Heart of Texas and the plumber used PEX. When I upgrade dash air in the future I was hoping to be able to use PEX for my long runs fitted to the flex fittings at the compressor. But my study of PEX doesn't show it handling the heat and pressure required on the high side. Boy if it was... I will probably use the Type K Copper when I tackle the project.
Thanks Ed

BTW: Are the folks in the Beaumont/Port A/Orange ready to secede yet? Here in Central Texas it is discussed a lot...

quote:

Originally posted by Stratosurfer:
BTW: Are the folks in the Beaumont/Port A/Orange ready to secede yet? Here in Central Texas it is discussed a lot...

Will you allow Yankees Me to join you down in Texas without being considered an illegal alien?

quote:

Will you allow Yankees Me to join you down in Texas without being considered an illegal alien?

All are welcome down here who determine to make their own way! Despite Houston, Dallas/Fortworth and Austin San Antonio: Texas is still a rural state: folks here like guns and freedom and don't like taxes so much. If you like that: we will like you! Come on down! Can't tell you how many 'Yankee' accents down here now. Yankees that love Guns Freedom and not so much governmental control are Texans at heart anyhow!

When Texas goes, I think Louisiana will too. If not, Texas is 103 miles west of here. We can get there before the gates close at the Sabine!

We have been ready to secede, at least for the last 8 months or so. As a fellow cajun, we have plenty of room, come on over and laissez les bon temps rouller!

Stratosurfer: The large condenser comes from Pro Air (sum whair up Nort") see: http://www.proairllc.com/condensers.html. I am using the 105 stainless steel unit which fit nicely in place of the puny condenser that came with the coach. It requires some new mount straps but will bolt to the same places the old one did - the muffler support housing and the floor of the engine compartment. I can take some pics if you intend to do thsi yourself. The swaged connections are your first job however as leaks will defeat any other upgrades.

Tom,
Thanks for all. I would certainly appreciate any pics you could take. Interestingly enough my coach with the R12 fitting are already swaged, I just need to find out if they hold any pressure for my dash air is not working and on the list to get back on line.
I am amazed that such a larger condenser core fit where the smaller one went. Mine is located below the engine compartment floor starboard side aft. I don't see how it gets any airflow except the electric fans. The air going through the engine compartment won't draft through it: I may have to move it somewhere.
This is a fairly large project as I need to get the dash air blowing, the engine water heating working; I'm going to let my mech look at before I commit to it...
How many evaporator cores does your coach have? I only see the one in my dash.

The intake air is through a dedicated vent door below the engine on the starboard side aft. The electric fan pulls air in and exhausts it under the engine.

On my coach there is an evaporator in the bedroom located at the bottom of the stack of drawers. Inside the door is the a/c and motor heat that is controlled by the dash air. There is a switch on the port side of the drivers chair marked AUX HEAT and that is the fan switch for that unit. It should be on whenever the dash air s on because it will freeze up (when everything is working properly).
The replacement coil is about twice as thick but only a few inches larger in height. I am attaching pictures but since I have not figured out how to link to that other site Bill NY has created he may move them.

Stratosurfer: I sent the pictures to photobucket and to Bill N.Y. because I can't figure out how to do this correctly. I don't know if the link will work but here is what I have: http://s451.photobucket.com/albums/qq238/hawk-57/
If this does not work I asked Bill to see how we can fix it.
tom

quote:

Originally posted by Tom K:
Stratosurfer: I sent the pictures to photobucket and to Bill N.Y. because I can't figure out how to do this correctly.

They are up now. Just got back from a wet weekend in the Pocono's