Air Conditioning Problems

Hello to all:
My wife and I (and five kids, under age 7) recently acquired a beautiful 1993 Prevost Country Coach in great overall condition. I picked her up in Dallas and drove back up to our home in New Jersey. The Coach was a dream...but a very hot dream. The over the road air conditioning did now work, forcing me to use the generator to run the basement and other two coach air conditioners as I trekked through Louisiana, Georgia, etc. They kept the coach cool in the morning and evening but were not able to compete with the heat and humidity of the south during the day. Also, I found that the both the front air conditioner (above driver head to the right) and the unit in the kitchen over the sink area both drip water after about 2 hours use. I took the coach to the Prevost service center in New Jersey and they supposedly serviced the over the road air conditioner turning it from blowing only hot air to blowing moderately cool air but certainly no cold air. My family and I recently moved down to Tampa and I must say that though I love the coach, it was a miserably hot trip with the five kids and the wife. I need to know if anyone has any advice about upgrading the air-conditioning and know of any good service people who might be able to do the work in Tampa. Thanks, Mike

Mike,
Give these guys a call. They should be fairly close to you. Thay are sponsers of POG and everyone who has used them has been happy.

http://www.coachworx.net/

Coach Worx, LLC
Entrances from both:
4501-B Ulmerton Road
or 13790-B Roosevelt Blvd
Clearwater, FL 33762
Phone: (727) 571-1133
Fax: (727) 571-1150

Phone Hours: Monday - Friday 7:00 a.m. to 5:00 p.m.
Email: coachworx@verizon.net

Mike,
I agree about Coachworx. My OTR air was not up to par so I had them check it out. It was 5 lbs short on R12 freon. They do excellent work.

My OTR air is so cold, I could hang meat in it during this hot spell. My cruiseairs will NOT keep the coach cool even if all 4 are running.
Ron

Mike,

Welcome aboard, it will get better....Coachworx is your best bet, Rick and boys will take good care of you.

Thanks so much guys. I sent them an email...we'll see what a complete air conditioning overhaul is going to cost me. I expect it to be ugly.

Mike,

Just a couple points to help you with the A/C...

Does your dash air work? The dash air has a separate compressor from the CC OTR and is independent. It is most likely still using R-12, but Coachworx will explain all of that.

The CC OTR has the condenser mounted under the bus in front of the axle and is prone to get dinged up and suffers from road debris. You probably have a bad leak somewhere in the system and they will find it using high pressure nitrogen. Also, when your system is up and running, it's best to use the high fan settings for all the locations as they have a tendency to freeze over on low fan settings. I experienced all of this and just wanted to pass along a little more info to confuse you!:p

Thanks for the info Tom. Prevost of South Plainsfield, NJ, completed a service on the OTR A/C two weeks ago and improved its performance slightly. It went from blowing only hot air to blowing mildly cool air but no cold air. Maybe they didn't check for leaks? I have emailed Coachworx as now the bus is in Tampa and close to their location. This is a great group of people and we are happy to have so much knowledgeable help. Mike

Mike, We have a 93 CC as well and also live in Florida (where its been cooler than New England). We have changed out the condensor units on two of our three Cruise Airs (the front two, behind the bumper, are new) and still use the 17 year old bedroom unit every summer night and it works great. Liberty Coach in Stuart is our best source for service as they are just down the road from us. They recently changed out the middle or galley ac, both the condensor and the evaporator units as "stop leak" had been added to the unit a couple of years ago and it had dimminished the cooling to the point that it was no longer satisfactory. When parked, the two front units do a great job if charged properly and the coils and filters are kept clean. The over the road CC system works fine, but as Tom points out, keep the fans on high or they will freeze up. It is a much smaller system than many of the Liberty coaches have for "over the road" air, and will struggle in real hot, sunny enviroments.

I'm sure your going to enjoy your new coach and will have fun learning about it. Feel free to give a shout if I can ever be of assistance.

Thanks for the info Mike. If you are trekking through the south during the day will the OTR air keep you cool enough or do you run the generator to run your cruise airs? Also, did you convert your OTR to the R134a? Our bedroom unit also works very well and keeps the bedroom cold but the rest of the coach is always hot. I've emailed Coachworx as others have suggested and will schedule an evaluation soon. Thanks, Mike

Mike,

Discussions about OTR and other air conditioning options on this forum have brought out the boxing gloves. But I'm tough and can take the abuse so here is the truth about OTR and all other choices. First, you have no choice. If you select a certain converter, with rare exception you get the AC systems that converter has deemed appropriate. This is not to say any converter is wrong, but to make very clear that as a buyer, unless you order a coach new, to your specifications you are likely to get what the converter typically builds. Having said that, if you want OTR your coach will be a Liberty, or one of the rare few OTR equipped built by other than Liberty.

Over the road (OTR) air is built by Prevost and is intended to keep a bus load of passengers comfortable traveling through the southwest in the mid summer heat. It is somewhere over 80,000 BTU of cooling capacity. To address your question regarding cooling all you have to do is determine how much cooling capacity other systems have. Cruise Airs and roof airs typically are around 13,000 to 15,000 each. Some coaches have "package" systems that are bay mounted and two are typically used. Each package system is around 26,000 BTU. I do not know what driver's air or the Country Coach air conditioning capacity is, but neither is the equivalent of the Prevost OTR.

All auxiliary AC units will run off the coach generators or shore power. There is nothing preventing you from running down the road with the generator running as many AC units as you see fit, but if you plan on doing that remember that roof airs are more apt to run efficiently since they are picking up ambient air for the condensing unit instead of heated air radiating from the highway.

No matter what you select keep in mind that every installed system has to be working correctly and if the performance of any AC system is compromised such as due to low coolant level or insufficient cooling it will not work to your satisfaction. Our coaches have a lot of glass and a hot engine keeping things warm and it takes a lot of AC to overcome those heat loads.

I have OTR and on a return trip on July 4th the OTR quit. I resorted to using the generator to run my Cruise Airs. Since I lost my driver's air when the OTR quit I can tell you the folks in the back were comfortable, but I was driving into the sun and I did not get enough cool air flow to get comfortable. The outside temps were in the low 90's. I fixed the OTR (it was a bad relay) and on the trip to Maine it had to be adjusted up because it works so effectively. I would not be without it.

Others with Prevost installed driver's air and the CC AC system have been happy, but the key is to make sure those systems and the Cruise Airs you have are working right. As to converting to R134, keep in mind it is not as efficient as R12, and if you can get R12 (still available often very cheap because there are now so few R12 systems around) I would definitely stick with it. R134 can find leaks R12 does not, and not only do you lose efficiency, but you should also expect to find a switchover if done right involves hoses and expansion valves.

I really appreciate all the information Jon. I will have Coachworx evaluate the coach and get the current systems up to speed and add additional cooling systems to the coach if needed to keep it at a habitable temperature in the hot Florida sun. It is strange though that one of the few Prevost specific service centers in North American (the one in South Plainsfield, NJ) serviced this OTR a/c not more than 2 weeks ago with mediocre results...we'll see if Coachworx can do any better.