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GDeen
03-20-2009, 12:57 PM
After looking at lots of late model XL shell coaches, one difference between most of the Liberty and Marathon conversions is the amount of A/C and heat. Many of the Marathons have 3 Cruiseairs and 40k Webasto, while the Libertys have 4 cruiseairs, 80k Webasto and OTR air.

I understand the difference b/w the OTR and non OTR systems. My question is are 3 cruiseairs enough to cool a 45' bus in hot weather while camped? Is the Liberty system overkill and Marathon sufficient or is the 3 Cruiseair setup marginal?

phorner
03-20-2009, 01:05 PM
In my opinion, you'll want the 4 cruise airs.

Sooner or later, one of the AC's will stop cooling, and the 3 remaining will be sufficient to do the job until repairs can be made.

Two ain't gonna cut it during the heat of summer unless you're in a very cool part of the country.

There's a LOT of redundancy built into the Liberty bus conversions, and this is but one example.

phorner
03-20-2009, 01:08 PM
And Gordon, there have been a few times when I've had all 4 cruise airs running to cool the bus.

And I have the electric bills to prove it :eek:

MangoMike
03-20-2009, 01:42 PM
Gordon,

I have both and the 40k Webasto does a great job in keeping the Marathon warm, the Liberty is overkill.

Three cruise airs will do the job, but Paul is right, it's nice to have a backup. My 2000 Marathon does have 4 cruise airs.

Mike

merle&louise
03-20-2009, 01:42 PM
Paul,

How many amps do the 4 cruise airs draw? I have 4 - 14,000 BTU AC compressors and my amp draw is about 44 amps or 11 amps per compressor.

You are correct with the 4 units being better than 3. In my 2 previous coaches I had 3 ACs in each; one with roof ACs and the other with cruise airs. Two out of the three units crapped out at the same time on both coaches. Talk about bad luck!:eek:

The OTR air is a big deal in my opinion. I wish I had it.:D

Buy the Liberty Gordon.:)

jack14r
03-20-2009, 02:30 PM
Depending on outside temperature I have seen as much as a 14 amp load for a cruise air unit,normally 12-13 amp load.I sure like 4 units,all 3 coaches that I have owned have not had the proper charge on the cruise air units,the performance of the cruise air is very sensitive to the correct freon charge.Johnny at AAP Power is the guru on how to charge the cruise airs for best cooling.

Joe Cannarozzi
03-20-2009, 02:50 PM
Jack did you have to make an adjustment on the charge on the bus you are in now? Interesting.

I like the cruse air for nothing on the roof and for the quieter operation. I will put up with their additional costs over roof air. Their temperamental nature with a slight incorrect charge I can do without. Not full timing the loss of basement space is a non issue.

If you could get AAP and that tech to make it to Ok. rally that would be a great thing.

Our bus is an orphan with OTR a/c and we used it a few times before getting it fixed.

I do not think we would be happy with one without.

The cockpit is a greenhouse traveling into the sun and if the OTR has trouble keeping things cold enough adding that front house a/c unit whatever you have keeps things nice even on the hottest of days. W/O the OTR it gets warm up front.

adamdegraff
03-20-2009, 04:17 PM
The 40K webasto is no problem at all. I have been comfortable in 20 below temps. And no, the webasto didn't have to run constantly to keep up.

I have 3 cruise airs. I have one compressor out, so I'm donw to two. I'm sitting in a Walmart parking lot right now. We are near Padre Island (southern tip of Texas.) The outdoor thermometer reads 85 degrees. It is 100% sunny. A bit harsh actually. The rig is cool inside with the two cruisairs. (rear and mid running.) Do I wish I had my third working? Yup! But I wouldn't need a fourth today. Add another 20 degrees to the outdoor temperature, and maybe I'd need a fourth, but I doubt it. But as previously stated in other posts, a 4th would be good for backup. But certainly not a deal breaker when looking for a coach.

Good luck.

~Adam

GDeen
03-20-2009, 10:37 PM
So in the situation where you only had 3 cruiseairs, but did have OTR air, with a parked heat soaked coach, the OTR air could be run on the big engine for a while to get the coach cooled and then the 3 cruiseairs could stay on top of it - sound reasonable?

Based out of Austin, there is no way in the summer to avoid at least one really hot day no matter which way we are going. Just don't want to sweat my way through that. Plus, my bulldog likes it nice and cool.:cool:

Joe Cannarozzi
03-20-2009, 11:08 PM
Yes the heat soaked coach is a great example and it happens a couple times a year minimum.

There is other house a/c systems besides the crusair. There are some with large central units in the basement and there are roof air.

I think if you have a large family or were living in it full time the roof airs have to be considered for the additional storage in the basement using them.

The cruseair have been around for ever and accept for electronics the units they have changed little.

I have been in 2 H's with the large central units in the basement for the house, carrier maybe, Alek Sawdust what are yours? They were both very impressive. Working noticeably effortlessly and very chilly.

In fact Sawdust has an H with factory OTR A/C and the house side sports that big basement central air and cruse airs both!

Even if you get OTR a/c it would still also be nice to have the front unit in the house to be able to run off an inverter.

jack14r
03-21-2009, 08:17 AM
Joe,Yes I had to adjust the freon charge on 3 of the 4.One was so overcharged that it would only run for a few minutes and then the high pressure would show up on the SMX controller and of course this would shut it down.It takes some time to get them charged for best performance,with a infrared thermometer measuring the suction temperature at the brass fitting at the unit,adjust the freon for the minimum temperature and it will have the max differential inside the bus.This is like someone said a while back to adjust the charge to(beer cold),except this is with a thermometer and not your hand.Either method will improve almost all cruise airs performance.It is amazing how well they perform when they are properly charged.Here in the humid south the condensation will have a steady drip off the suction side and the coach is cool inside even on a 100 degree day.

Joe Cannarozzi
03-21-2009, 08:43 AM
We have never had all 3 set right, together.The one in the kitchen is bitter cold on the hottest of days so I know the potential is there for the other 2.

I need to stop procrastinating and get the tools and knowledge to do this myself.

GDeen
03-22-2009, 12:46 AM
Bottom line, there is an excellent deal on a late model Marathon XL out there with nice colors, layout, etc.....biggest downside is no OTR and only 3 cruiseairs. That is holding me back for sure.

hhoppe
03-22-2009, 09:17 AM
After owning a 40 with three cruise airs and now a 45 w/ 3 cruise airs and the over the road AC it would be a hard decision to go back. We did survive in the 40 with the generator running going down the road.

truk4u
03-22-2009, 09:46 AM
Gordon,

Depending on the vintage of the Marathon, it will run 2 cruiseairs off the inverters while driving. With dash air and 1 or 2 cruiseairs running, you shouldn't have a problem without bus air. With good house batteries, you can also run cruiseairs off the inverters while sitting and not driving. Mine was a 97 and with new batteries, I could run 1 cruiseair for 4 hours or 2 for 2 hours and then the autostart would kick on the gen.

I wouldn't pass up a nice bus/deal because of lack of OTR.

Joe Cannarozzi
03-22-2009, 09:51 AM
Gordon

Truk does not pass up ANY good deals on buses. You better hope he is unaware of the one that you are looking at.

Just kidding Tom

phorner
03-22-2009, 10:03 AM
Gordon,

Before we purchased our Liberty, we test drove a 45' Marathon XL on a hot August day and we were comfortable enough with 2 cruise airs running off the inverters. Our test drive was not very long, probably 30 minutes or so.

However, that being said, once you have driven a bus with factory OTR bus air, it's REAL HARD to go back to driving one without it!

We travelled through nearly half of the United States last summer and the OTR bus air was wonderful. NOTHING will cool the bus down faster than running the bus air.

So, bottom line, should the just absence of OTR bus air be a deal-breaker? Probably not.

BUT, the rest of the bus really would have to WOW me :D

JIM CHALOUPKA
03-22-2009, 10:07 AM
Gordon. Remember the plan! Stick to it! Make the two column list snd compare the pros and cons.

In the horse world there is a saying "the perfect horse has no color" You can change the color of the bus easier than you can the mechanical equipment.

Another horse world saying is "it's easier to buy a horse than to sell one"
If you are impatient and not careful in your purchase it will be costly to "get happy"

I think they apply to a bus to some degree.

You said you found an XL, I take it as a forty foot and not an XLV a fortyfive?? According to Harry that might make a difference.

JIM

Coloradobus
03-22-2009, 11:07 AM
A bench for Marathon Coaches running 2 a/c' units off of inverter is 1997 40 footer called Coach 400. I have been told its the first Marathon to be outfitted with 2 4000 watt Trace Inverters. Jello-Jeep could verify this since their coach is newer. Coaches prior to #400 had Marathon's own version of OTR called "MAC II A/C, or you run the genset to power house A/C units on the road.
Very rarely to we run more than the dash air. On hotter trips we implement the A/C Select switch and run the Salon cruise-air running down the road.

GDeen
03-22-2009, 03:37 PM
Clarification - it (they) is (are) indeed an XLV...

After looking at a 40' Liberty Steve had at California Coach and comparing to a 45', Momma says bring on the bigger bedroom and bathroom of the 45 footer. Certainly the 40' has a lot of advantages but the extra space is hard to pass up.

Going to take my time for sure. Have to go back to work for a living this week, but I am trying to find a hole in the schedule to jump a flight to FLA, Want to check out a couple of buses down there in person.

By the way, I can't say enough about Steve Bennett - what a great guy. Very patient with all my questions and couldn't be more honest and straight shooting with his opinions about the different convertors, systems, layouts, etc. Most importantly, his opinions and answers to my questions were never weighted towards trying to make a sale on one of the coaches he has right now which I really appreciate. Certainly makes you want to do business with a guy like that.

adamdegraff
03-23-2009, 12:16 PM
What about Marathon's over the road air? Yes, mine has a smaller, OTR compressor living in the spot usually reserved for factory OTR air. Mine is called MACH, or Marathon air conditioning and heating system. It really does the job. I think OTR air is sized to cool a bus with 40, mouth breathing passengers. The marathon system is smaller, but cools the bus perfectly in all cabins. In fact, my wife's complaint is that it makes the bus too cold. (I keep telling her the controls are within reach in each room and all she has to do is turn the knob up or down, but she doesn't listen:-)

I thing the system work really well, and I miss it. Yes, the compressor went bad I think. So I am in the process of getting this fixed. I have calls into Marathon. Funny... here I am talking about how well this system works... yet it is currently broken :-)

I'll try to post a photo of it.

Best,

Adam