[Per]

Unless I had a newer coach with technology like Mark’s bus I wouldn’t buy a bus without OTR.. we are in Texas and it’s very hot in the summer…I am fanatical about keeping the bus cool inside when on the road …. I even leave the bus running until I am completely hooked up to shore power and my a/cs are running and doing their job… It’s VERY hard to cool a hot bus when its 100 degrees outside so I start with a cool bus and have no problem…I even hose down the slab under the bus before I park if it’s that hot and that makes a huge difference with the Cruisairs.

We have only had 2 Prevosts both Hs with OTR and Cruisairs… Our first H was a 1998 Vantare with 2 slides and wouldn’t have been happy without OTR in Texas… both OTR’s have never givien us a problem…I have to cover up with a blanket sitting up the front as it’s really cold. and if I driving long pants and a jacket… but the bus is cool !!

To each his own for sure, but that’s what works for us..I think there is a big difference if you’re looking for an older coach and OTR would be on the top of the list for us.

Cheers, Diane

[Glenn]

Jon

Have you ever looked into Lithium batteries. They are as I stated. The reason I asked the question is my interest and study in solar energy and lithium batteries. Two of the first questions that are asked is How many wts on top and how many amh in the battery bank. Lithium work well with gennys as well.

I am not sure why you think a change over to lithium is difficult. The switch is not difficult at all. Li batteries can be discharged to well below 80%. Efficency in both charging and discharging is nearly 100%. Charging/discharging cycles are 5000 or compared to leadacid which can cycle about 400-500 times. Environment impact is much less as Lithium is much cleaner. The weight I think is the biggest consideration. At 1/3 the weight you can put in a lot more battery power or keep the power the same, saving space and weight.

Take a look. You might be surpised what you find.

Batteries cannot run the ac, unless you have a really realy large battery bank, but they can run the coach. Less generator noise and less fuel.

My question of how many ah were in the battery bank was not based on a purchase decision just an interest in Lithiums in a Prevost.

[Ron]

We just had solar put on our house in the California desert back in March. The solar company failed to mention that solar charging falls significantly in heat (115-123 degress this summer) . I thought our system was not working correctly until I was enlightened that heat causes the system to lose voltage.

So, in the heat of the summer, with the bright sun shining, we were producing about half the energy than in April. All and all, we will do fine at the end of the year as everything will balance out. I would love to have a battery wall so that we could go totally off the grid with a natural gas generator for back-up. Maybe one day.

Safe travels,

Mark

[Ron]

Mark

Yes solar losses energy when hot. I wonder if you could put a sprinkler on it to cold it down. Oh CA. Ya’ll probably have water restriction.

Solar still has great difficulty with running the ac. Other wise you should be able to go off grid…Now if you go really really really big solar you might be able to run the ac and the heat. THen you could tell the utilities to go fly a kite.

[Ron]

Patrick

Thanks for your thoughts. I like your thinking.

Ron

[John]

Dianne

I like the way you think too. This year you do ‘nt have to be in TX to get the heat. Ive heard of folks in AK where temps were in the 90’s. If you believe in global warming temp will continue to rise. Thanks for your thoughts

Ron

[Alvie]

Ron, When you buy a coach, and when you put out the $$$$$$$ to convert over to LI lets reopen this conversation.

All I know for sure is my 4 8D AGM are adequate for how I have used my coaches and having more battery powe does nothing for me. Further, I am a generator guy so if I am not connected to shore power I am exrecising my generator because it allows me to be an absolute energy hog for about .4 to .5 GPH.

I am not calulating watts, amp hours, or battery capacity because as long as my batteries make it through the night without needing to recharge because my refrigerator is pulling too much power I am good to go. I have zero expectations I am going to run A/Cs or Webasto solely on batteries as long as I have my Kohler 20KW generator.

[Archived]

Jon

Everything you say is correct for you and the many other good folks who use the bus like you do. A 20k generator is a wonderful thing and cheap to use.

When you average the cost of Li vs lead acid, Li comes out cheaper over the life of the batteries. And You gotta admitt they do weigh 2/3 less than leadacid batteries. That may not mean much to those who drive a bus. If we are going to have to have batteries no matter how you use them, Li is the way to go.IMHO.

Summer has gone from being warm in most places to being HOT. Even AK is getting 90′ temps for the last several years in the summer. You used to be able to run north to get away from the heat. Not always the case, so I want an ac that can handle the temps no matter where I am.(I will not be in the desert in the summer)

The infomation from all the folks on this site is very useful and I hope to hear from more of you. Thanks for all the replies.

Ron

[Ron]

Jerry and Gayle

I think your perspective is correct. I have been in bus that had OTR air and they cool amazingly well. Those without do cool, but not as well. (I am looking at older models) I am sure the new ones do a much better job with roof air.

Ron

[Archived]

Andy

Nice looking coach. Thanks for sharing

Ron

[Ron]

Don

Thanks for the imput. I thank you.

Ron

[Ron]

Putting Li aside, if staying cool is important you are either going to limit your options, or you are going to modify the coach you select.

Let’s start by recognizing a coach that does not have Prevost OTR has some inherent issues with cooling because in hot ambient temps there is no substitute for a large BTU output A/C system. Everybody has their own interpretation of what is comfortable but what requires no translation is output. With the least effective Prevost OTR system rated at 80,000 BTU and later model systems up to 109,000 BTU that will keep you comfortable even as hot exterior temps are being absorbed through the windows and skin of the coach. Our coaches have a lot of mass inside and what has to be recognized is that on hot days, if the interior or even parts of the interior are allowed to get warm the house A/Cs are working overtime to try to pull the temps down so you want a coach that can be completely cooled and that cool temp maintained.

After a day of driving in the heat imagine how hot that bedroom will be if it has not been cooled all day, and then not only does the contents of the room need cooling, the system is fighting with an engine that is sitting beneath the bedroom adding heat.

The solution is if no OTR you need a coach with sufficient house A/C units that will cool the coach and unless highly equipped with ample inverters and alternator you need to plan on using the generator full time.

Cruisairs get a black eye because while they are excellent for keeping a parked coach comfortable the basement mounted condensing units cannot handle the heat radiating from the highway in the hot sun so when you need them most it is not uncommon for them to shut down. Before taking that as an endorsement for roof air units they can face the same issue if the ambient temp is high enough because they are picking up air for condensing that is radiating from the hot roof of the bus and on another site there was a lengthy thread about issues of that nature this past summer. But they are better for use while driving for sure.

Since everything about our coaches is a compromise keep in mind no matter what direction you opt to go you are still going to give up something. OTR will cost you the equivalent of about 1/2 bay of storage and if it is an old system that is all original you need to be prepared for needed maintenance or rebuilding. If you have Cruisairs you need to understand if the OTR goes out during a trip, your Cruisairs may not work for cooling if the ambient temps or road surfaces are hot. If you instead have roof airs with OTR they will likely work as backup to the OTR, but most owners report unacceptable noise levels due to the roof mounted units. Those noise levels tend to be tolerable because if a roof air fails they are relatively cheap to replace so some shortcomings can be acceptable.

At the very least a 40 foot coach needs 3 house units, and a 45 needs 4 if you are dealing with high outside temps and if you want some cooling if one of the units fails to work.

Getting back to Li…………Your promise of cost effectiveness over the long term has not been met with the current real world experiences. At some point as the industry settles on standards and volume production numbers reduces the costs it will most assuredly make economic sense. Some Li installations have had failures and the promise of rebuilding or repairing the batteries has proven to be untrue. So those early batteries do not have drop in replacements or a means of rebuilding them and the cost to repair a battery failure in a coach far less than 10 years old has been to replace the entire set for about $15,000 and what makes it worse is there is no good other option. When the industry has standards such as the lead acid batteries of today that problem goes away but right now there are none. Batteries from one manufacturer are not compatible with another manufacturer because of the need for devices to manage the entire system and balance all the cells.

Additionally Li does not have what we would consider a suitable “drop in” that I am aware of. There are claims to that effect but if I want to replace my 4 8D batteries I have to have additional devices to pull both 12 and 24 volts, maintain the balance, and possibly deal with auto-start issues on a battery that does not lose voltage, but instead just shuts down at some point.

I think we are getting closer on Li, but remember, our coaches are “recreational” vehicles and unless you would enjoy the role of test pilot and don’t mind sorting out issues that arise as you use your coach I have some reservations regarding if the time is right for Li.

[Dana]

LI is the future no doubt. Jon is correct, you can’t just drop in some LI’s to replace my current (6) 4D’s without addressing the 12/24 needs, upgraded inverters, auto-start parameters and alternator requirements. Do it as a package similar to what Ben has been discussing, yes that works, but not a simple drop in replacement.

So anyone out there that can factually show a real world working bus house battery drop in replacement for 4 or 8D’s, batteries only, please inform us.

[Deleted User]

Jon

You do make some good points. There is no standard/universal model. Sometimes they are difficult to find, depending on where you are. I have not read anything of complete failure of the system. Not to say there have not been, I just have not read about it. Some companies have been far less reliable than others. Some companies have gone out of business because they did not know what they were doing. You need to find a company that has a good reputation. There are no “drop in” so each bank is custom made.(sort of). This technology is new for RV’s so those who are installing Li are test pilots. What is the saying “the pioneers take the arrows in the back”.

According to the reps who are making these things, they are stil claiming cheaper in the long run.

Hope you have had a great Labor Day

Ron

[DON]

Tom

You are correct on both points. There are no drop in ready systems. Each one is custom. They are the way of the future.

Ron