Roof Airs

[garyde]

The Liberty Coach has 4 Cruise Air split units. The condensor and evaporating coils are located in the bays. (2 in the center of bay #2, 2- in the front behind the bumper.) The bedroom has 1 fan coil and contol, the Galley & living have 2 fan coils & contols and the the driver and passenger have 1 fancoil and control. They run off of Shore power and/or Generator power.
Because the condensor coil is beneath the floor , it recieves its air from below the Coach. This can be a problem if the outside air temp is too hot and the road is hot. It will shut down the A/C units.
These same units can also be used for heating the Coach.

Similar to these Marine units: http://www.dometic.com/enus/Americas...ctdataid=85332

[Kenneth Brewer]

Short answer....no.

What he said. We have had 3 roof airs on a 35' coach, and they were sufficient for that length, but we had to run all 3 (to keep the bedroom, kitchen, and bathroom cool and the ammonia cycle refrigerator happy), and that required the generator (no inverter/s). We have had 1 fail on one occasion, and 2 fail on another occasion. In those cases, of course, running or parked, 3 roof airs are insufficient. OTR will cool a heat soaked coach (over 110 outside) in relatively short order, and then seem to loaf. In those conditions, parked, do not consider any roof air (or cruise-air, for that matter) coach with less than four units. Or you will regret it, in my opinion, for my 2 cents.

[Danss]

have 45 foot with 4 roof airs and have never run more than 3. Only run 1 plus dash air while moving. have traveled thuout the South. Tx. La. Ms. Ga. Fl. Tn. Al Sc. Nc. Co. Nm. I do beleive You could have a problem in the desert with just 3.

[Mark3101]

The Liberty Coach has 4 Cruise Air split units. The condensor and evaporating coils are located in the bays. (2 in the center of bay #2, 2- in the front behind the bumper.) The bedroom has 1 fan coil and contol, the Galley & living have 2 fan coils & contols and the the driver and passenger have 1 fancoil and control. They run off of Shore power and/or Generator power.
Because the condensor coil is beneath the floor , it recieves its air from below the Coach. This can be a problem if the outside air temp is too hot and the road is hot. It will shut down the A/C units.
These same units can also be used for heating the Coach.

So, from reading this thread, I guess that there is no "Perfect" system out there, and either roof airs or the combo of OTR air & cruise airs all have a potential downside. The original posters question about 3 roof airs I think has been answered as a big "NO" but 4 roof airs or the OTR /Cruise air combo would work ok.

I am happy with my roof airs, and it appears that some are happy with OTR air...looks like it is more of a personal preference thing and shouldn't be the sole reason to disqualify a coach from consideration.

[Jon Wehrenberg]

I have had two buses with OTR and Cruise Airs. I have had the OTR quit for the same reason Deb and Eric's quit and that was a failed circuit breaker. But when it quit it was a day in the 90's and I found out that when heat radiates off of a heat soaked highway the cooling air available to the Cruise Air condensing units is insufficient to keep them operating and they shut down. If the coach had roof airs it would have been picking up clean air high off the highway that was not being heated from the highway.

Cruise Airs however have their place and when parked (or modified as described below) they work great because the ground beneath the bus is shaded so there is air capable of cooling the condenser effectively. Their benefit is they are relatively quiet and they are not built to be replaced so they tend to be reliable and have a longer life than the typical roof air. Some owners have made modifications to get good performance from Cruise airs. I know of one coach that has an improved condenser fan system to jam more cooling air across the condenser. I know of one that has had a pressure switch installed and that switch controls mister sprays when internal pressures creep up keeping the units functioning. So the short answer is Cruise Airs are not the best thing if you need to fall back on them. Having said that I had a relay quit on my current coach last summer and I needed to run the Cruise Airs. I was surprised when they worked very well despite high ambient temperatures and did not shut off like my Cruise Airs did in my first coach. So maybe those that do fail to function are either in excessively hot temps or something has changed.

I don't know of anyone whose roof airs shut down when the highway temps are excessive.

[Mark3101]

The extra bay space used for the Cruise Airs could be an issue for some I guess, otherwise I don't see any downside either way. Since my bus is parked until spring, I don't have to worry about air-conditioning for awhile yet...

[Pete]

The IDEAL set up is OTR, 4 Roof airs, and Driver/dash air. Should your OTR fail, start the genset, run the dash air (especially if headed west in the summer) to keep the driver and co-pilot cool. Sort of like wearing a belt and suspenders! Trust me, headed west in the afternoon sun, even 4 roof airs will not keep the driver and co-pilot cool without dash air! You hardly ever see this set up...but it would be ideal. Next best set up is OTR with 4 roof airs for back up.

[Jon Wehrenberg]

In both cases I applaud Liberty for the Cruise Air placement. They were located behind the bumper (2 units) or centrally located behind the 2nd bay. Neither location seems to rob valuable storage space yet when necessary all units in either location are easily accessed for service.

I don't know where other converters locate the condenser units.

Pete nailed it for a belt plus suspenders set up.

[CAPT MOGUL & Sandy]

First of all Doug and Lee, WELCOME to this family!!

Ed and I have 2 buses, and both have roof airs (3)each. We have NOT had any problems with cooling. Both our buses are Royales. One is 40ft. (which by the way is for sale just down the road from you at Luxury Coach Brokers with Ken Robertson)He is one of our Sponsors. The current bus we have is a 45ft. with 3 roof airs. So far we have not had any problems with cooling while sitting or underway. We use the dash air while underway. I don't think, as one has already stated, that this is what you need to FIRST consider when buying your bus. You will know the one instanly when you see it. There are alot other decisions which you will be making and I'm sure you will understand what all are saying after looking and looking!!

That is my 2 cents now.
Again, welcome to this FUN, INTERESTING, and CRAZY family. You could join us at the Oysterfest in March at Bella Terra and I'm sure there will be a variety of conversions there. I'm sure we could give you tours of all our buses.
Sandy

[jack14r]

Jon,I heard recently that when Liberty did the first 3 slide which does not have OTR that they found that there is a vacuum created under the coach at a certain speed(like ground effect on a flat bottom race car).With this new information,assuming that it is true,temperature may not be the problem while underway but instead no air flow to cool the condenser.Also there might be certain speeds that there is air flow and other speeds that the vacuum is created.