[Bill]

Well this is always a fun topic. Lots of threads here and lots a strong opinions on both sides. It’s almost like asking which converter is better Marathon or Liberty. Most with Bus air say they can’t or won’t live without out and those that don’t have it say they don’t need or want it.

Having or not having bus air was not a key factor for us in deciding what bus we purchased. Other things like layout, bunks and decor is what drove our decision.

We purchased our 2007 Marathon in 2012. It has 4 roof airs. In over 8 years and well over 100,000 miles, I can count on one hand the times we have needed 3 roof tops to keep us comfortable. Most of the time my wife is complaining it’s too cold with just 2 on in addition to prevost dash air.

Hope that helps.

Bill

[Roscoeapproved]

It is unlikely a buyer has a choice regarding bus over the road air as installed by Prevost. If you want OTR the vast majority of coaches with it will have been Liberty conversions. To get an OTR coach from another converter will be a hit and miss proposition.

There are significant benefits to OTR, but there are drawbacks. You have to determine the ultimate benefit to you. We have had nothing but Liberty Coaches with OTR. The lack of it was/is a deal breaker for us. We want to have the entire coach at the same comfortable temperature, and for me a comfortable temperature is likely too cold for most people. I set the system for 70 degrees. Regardless of whether it is winter or summer when we arrive at an RV park the entire coach and its contents are at a comfortable temperature.

The reason I stress the entire coach is at a comfortable temperature is because it makes it very easy for our house heating and A/C systems to not be overworked trying to cool down or heat up portions of the coach that were not at the desired temps while driving.

I am sure a coach without OTR can be kept comfortable using basement or Cruisairs, or roof airs but in some instances it might require running a generator to handle the power needs. It is all about numbers and outside ambient temps. There is no way a typical house A/C unit with 13,000 to 15,000 BTU output can make the entire coach comfortable for me, so I would have to run 3 or 4 to accomplish what I can do with the push of a single button on our OTR controls.

If we allow the coach to be overheated such as starting a trip after the coach has been sitting in the sun, the OTR with up to 106,000 BTU OTR output will bring it to a comfortable temp a lot quicker than 3 or 4 roof airs with 52,000 to 60,000 BTU output.

The downside is OTR uses the equivalent of 1/2 of a bay. The condenser uses a shallow bay on the passenger side and a similar amount for the evaporator on the driver side. If the coach is used as a second home and spends a lot of time at an RV park that space becomes more valuable than the ability to have OTR.

The bottom line is your definition of comfortable. I had an aunt and uncle who lived in FL and to them 85 degrees was comfortable. At that temp I am gasping for air and at 70 I am comfortable, and if it is cold out as long as the interior is somewhere around 60 or 65 I do not even turn on heat or the Webasto.

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Jeff and Lindsay

91 Marathon XL

[Jim/Chris]

“Most of the time my wife is complaining it’s too cold with just 2 [roof airs] on in addition to prevost dash air.“

So you removed the OTR A/C compressor and replaced it with a smaller one, just to run the driver AC ? And you run the genset to run the roof airs ?

[Jon]

Only pay for what you need Liberty, Liberty, Liberty

got a 2 1/2 ton house unit in mine. Never run OTR.

[Dick]

I will never own a coach without OTR.

[Jon]

I will never own a coach with OTR.

[Archived]

And Jimmie and I are both right.

[Art]

Agreed.

[Paul]

Removed due to my reading incomprehension.