What does this mean? i see it mentioned frequently as an option but thought all Prevost's have a/c.
Is it a seperate or preferred system?
Printable View
What does this mean? i see it mentioned frequently as an option but thought all Prevost's have a/c.
Is it a seperate or preferred system?
OTR air is a system that has a separate compressor that runs off the engine. It is in addition to the dash air on some coaches. Prevost OTR air is the best and most expensive. Country Coach installs a significantly cheaper system that does a good job if working properly. It does not have the output that the Prevost OTR air has. OTR air allows you to cool the bus while traveling without running the generator.
OK. Thanks.Quote:
Originally Posted by Roadrunner
Is it a common option? And does it cool just the front portion or is it ducted to the whole coach?
It cools the entire bus, most comes out at the bottom of the windows. The factory system is designed to keep a charter bus with all its windows and 50 large people cool on a 90+ degree day.
I give it a thumbs up. I would not buy a bus without factory OTR a/c or some form of it (CC & Marathon), it would be a deal breaker for us.
You can easily spot a coach with factory OTR air by the louvered bay doors 3rd bay back, both sides.
hillndale, on you new bus look in the engine compartment. In the lower right side is the large OTR AC compressor. If you have it you lucked out.
The image depicts the OTR compressor. It is grey.
The description can be reduced to numbers.
Over the Road Air (OTR) is a whole coach AC system that is about 80,000 + BTU. It is used while driving since it is only engine driven. It is extremely effective. Only Liberty consistently builds and sells coaches with OTR, and a Liberty without OTR is very rare. Other converters will buiild or have built conversions with it, but they are far less common.
Those that build conversions without OTR justify that on the basis of it saves bay space (in actuality only the equivalent of 1/2 bay, if that), that their coaches can run house AC units from an inverter or engine driven generator, or they install a system as Dale says that has less output. The reality is that converting a coach with OTR is a challenge. The converter not only has to provide ducting for the OTR, but the air flow has to be balanced making an interior design an engineering challenge.
Without OTR a coach will typically have 3 or 4 Cruise Air units, 3 or four roof airs, or a couple of "package" systems. The Cruise or roof airs are likely to be around 13,000 BTU for 39,000 to 52,000 total AC capacity. The packages are likely to be around 26,000 BTU for a total of 52,000. The short version is that OTR is significantly more capable than anything else.
As long as the coach temperature is maintained it is likely the other systems will be adequate. Where problems arise is when the coach is heat soaked and the owner wants to cool it down. It will take forever. If the coach has OTR an owner can run the engine and the other AC units and in a very short period of time the coach is cool.
There is no way Cruise Airs will cool the coach in the desert southwest when driving down the road. Heat radiating from the road surface will not allow the condensing units to adequately cool the hot freon gas and they will shut down. In this instance roof airs will be the better choice. The arguments about which is best are all over the place. Those opposed to roof airs talk about the noise level. Those opposed to OTR talk about lost bay space or the fuel and HP required to run it.
Personally I will not own a coach unless it has OTR. It is at the top of the "must have" list. I will look no further once I see a coach does not have it. Others are likely to have the opposite opinion.
Wow...thanks for all the great info everyone.
This leads me to the next question- what is cruise air?
Cruise Air units are mounted with the evaporator coil and fans in the living area of the bus, with the condensing units remotely mounted in the bays or behind the front bumper. The advantage to them is they tend to be fairly quiet.
Thanks. Are they not as cold or as efficient? i haven't seen any conversions with this feature for some reason. kind of rare?Quote:
Originally Posted by Jon Wehrenberg
CruiseAir units are quite common in bus conversions. Look at the roof and if there are no AC units up there you can bank on the coach having three or four CruiseAirs. Bruce's coach is an exception and there may be a few others. I prefer CruiseAirs and I'm sure there are folks who like roof air units. Both will cool a stationary coach when functioning properly. The advantage to roof air is, like Jon says, they will cool better while the coach is traveling. But, a bus with Prevost OTR air is the best option for summer travel.