Keeping Cool at 112 F

[ATeam]

We drove across the Mojave desert yesterday afternoon, The outside temp ranged from 105 F to 113 F as we drove. This is the hottest temp we have encountered for an extended period of time since we got into this truck.

I was in the sleeper with the curtain closed and unaware of the outside temp until it got a tad warm inside. With the bunk unit AC (not roof unit) set on high and the sleeper warming up, I went up front to see what was up. The 112 F temp both surprised me and explained why the sleeper was warming up.

ARI is the sleeper manufacturer. They supplied window blackouts with the sleeper (insulated pads cut to fit each window, made to keep light and extreme temperatures out). The 132" sleeper has three large windows. There is a lot of space to cool and a lot of uninsulated surface area (the windows) for the heat to get in. Putting in the blackouts solved the problem. The bunk unit was then able to keep ahead of the heat. In the cab, the Volvo truck AC kept Diane cool and comfortable the whole time.

I share this because, from time to time, people ask about how sleepers perform in extreme temperatures. ARI passed the test yesterday, that's for sure. I was wearing blue jeans and a polo shirt. We drove under hot sun for hours. Being focused on my work, the outside temp did not even enter my mind until it reached 112.

From previous experience sitting in desert temps with the truck engine off, we know the generator and roof unit do the job too. That setup provides the additional option of starting the generator and using the roof unit to supply AC if the truck AC fails while we are driving. The roof unit and truck AC are independent systems.

 

[Broompilot]

My biggest failuire with my Bentz was no insulation on the Floor. It got cold quick in the winter at 15F or colder and in extremem heat the same thing could not stay cool comfortable yes but a bit to warm.

The Volvo sleepers are WOW very well insulated maybee to well if there is such a thing.

 

[greg334]

My biggest failuire with my Bentz was no insulation on the Floor. It got cold quick in the winter at 15F or colder and in extremem heat the same thing could not stay cool comfortable yes but a bit to warm.

The Volvo sleepers are WOW very well insulated maybee to well if there is such a thing.

Broom,
I think the floor insulation is a problem for many sleepers and they are finally catching up. My Bentz (*cough) sleeper is a horrible place to be with any extreme temps. The workmanship has a lot to be desired and there is no excuse for it, even at it's age.

I am getting to finish off the wall insulation this week and will try to get to the floor, but I will have to lift the sleeper up about 4 inches to get it done right.

As for Volvo, yes they make a very good sleeper but Phil's truck is a day cab which I expect is as well insulated as one can get. I know this is the vehicle for Toters and seen a few sleepers taken apart to expand/remodel.

This week is a a couple hundred mile trip in a Cascadia and I hope it will live up to my expectations of being well insulated and quiet. Maybe I can squeeze in a run in a Volvo too?

Oh and by the way Phil, I am glad you are comfortable while traveling across the desert. I too had an experience, my change holder melted on the floor of the cab, the A/C could not handle the heat and it was a constant 90 in the cab and sleeper and I had ice melt at a very fast rate than I ever had before. Thanks for the info.

 

[ATeam]

As for Volvo, yes they make a very good sleeper but Phil's truck is a day cab which I expect is as well insulated as one can get. I know this is the vehicle for Toters and seen a few sleepers taken apart to expand/remodel.

Actually, the Volvo day cab is not "as well insulated as one can get." Because it is a day cab and not a sleeper truck, the winter insulation package option was not available to us. That is one of the very few things I would change about the truck if I could, add winter insulation to the day cab. But I can't so we take what we can get. Even so, that cab is the most comfortable we have ever been in; toasty warm in the winter, comfortably cool in the summer.

 

[EASYTRADER]

I changed the refrigerant in my APU AC unit. It used to have R-22 which is used in most homes, I replaced it with ES-22 which is non-polluting direct drop in, two weeks ago in Laredo TX, my APU AC was dropping the temp by 30 degrees, the outside temps were in the high 90,s low 100s,

Anyway before the refrigerant change, my APU couldn,t keep up with the temps in summer.

My carrier APU is a poorly designed POS anyway, but the new refrigerant has helped immensely.

There is also a direct drop in for r-134, I'll probably switch out my truck ac also.

The stuff is manufactured by a company called enviro-safe

 

[ATeam]

Interesting info. Here is the link to the Enviro-Safe web site. If the refrigerant is that much more efficient, I wonder what kind of reefer fuel savings that might translate into?

 

[greg334]

Actually, the Volvo day cab is not "as well insulated as one can get." Because it is a day cab and not a sleeper truck, the winter insulation package option was not available to us. That is one of the very few things I would change about the truck if I could, add winter insulation to the day cab. But I can't so we take what we can get. Even so, that cab is the most comfortable we have ever been in; toasty warm in the winter, comfortably cool in the summer.

Well you are right about that Phil, in comparison to other day cabs. Nevertheless, that Volvo has some additional insulating qualities that others don't, more specifically Freightliner.

 

[OntarioVanMan]

Well you are right about that Phil, in comparison to other day cabs. Nevertheless, that Volvo has some additional insulating qualities that others don't, more specifically Freightliner.

Surprised they don't insulate the freightshakers better...that way you could turn down the radio and still not hear all the rattles....

 

[arkjarhead]

Phil,
Trucks have come a long way since my great Uncle Herald first starting driving across that desert when he got out of the Army after WWII in the late 40s. He said they used to pack their radiators down with bags of ice to help keep the truck from overheating, and they would put ice somewhere else under the hood so they could turn of the fan (no a/c) and this would draw air across the ice and blow it into the cab. A homemade a.c I guess. He said it will still be so hot they would drive with one hand, and the steering wheel would get so hot if you put your hand on it where it hadn't been previously covered it would blister your hand. He also said the metal accelarator would melt a little dip in the middle of your boot and you could see where it had been.

He said alot of truckstops in those days had bunk houses as they called them where you could pay something like a dime and sleep inside under fans an a/c during the day and cross the desert at night if you had time to wait.He said the bunk houses were big rooms filled with bunk beds. Kinda like a military barracks. He said you didn't have to worry about your wallet being stolen either. It really has changed. He said they also had big open showers back in them days.

 

[ATeam]

Well, I suffered through the desert heat too. I mean, come on! There were a few moments in the sleeper where temperatures rose slightly above room temperature and I actually felt warm. It was enough to make me leave my seat, make my way to the cab, and make a sincere inquiry about the temperature outdoors. It was THAT bad! But I'm no puss. I made it through without complaint.

 

[TeamCaffee]

Our daughter just moved from Little Rock AFB to Nellis AFB and wow was it hot at Nellis. She owns a 38' Camper and it was amazing how warm the camper was getting in the afternoon with only a palm tree for shade.

When we are in that heat we try to get next to a big truck for shade and then we put up all of our blinds. We have still found that in the afternoon our Rig Master struggles to maintain the temperature in the truck. Bob did check the coolant level in the generator and found it to be a little low so he recharged the system. We were in Laredo at this time and did not have any troubles with the rig master working in the truck but our darn shade trucks kept pulling out!

One of the first things we will be checking before we ourchase our next sleeper will be how well it is insulated.

Sounds like if we see Phil in the desert we just need to go visit him and Diane.

 

[ATeam]

All sleeper manufacturers will tell you how well their units are insulated. I don't know of one that will say theirs is poorly insulated. One thing to look at is the floor. ARI puts three inches of insulation in the floor, which is thicker than some.

The manufacturing process is different than some too. I don't recall the name that describes ARI's floor manufacturing process. The end result is an air-tight, pressure tested, leak proof floor. If you tour a sleeper manufacturer's plant, ask to see how the floors are made.

The Onan generator with roof unit setup is commonly used on RVs and RV trailers. They have way more space to heat and cool than a truck sleeper (multiple roof units are used on large RVs). Using the same setup on a truck sleeper, even a large one, provides plenty of reserve capacity. Also nice about that setup is the roof unit needs only power from the generator to work. It is otherwise a self-contained system that can be easily removed and replaced if it craps out.

We paid just over $1,000 for the roof unit brand new. Most any RV dealer can work on it. But at that price, it may be easier to simply pop a new one in if the old one fails.

When I read of things like generator refrigerant leaks, temperature control electronics that are not working but are not properly diagnosed, repeated trips to dealers to fix the same problem, and four-figure repair bills, splitting the functions seems to make more and more sense.

Use the generator to do one thing; generate electricity. Use the roof unit to heat and cool the sleeper. For truck engine warming in the winter, the generator can power an electric block heater and oil pan heater. For truck battery charging, both types of generators work the same way.

With components dedicated to specific functions, if a heating, cooling or temperature control (electronics) issue develops, the worst case is you will have to replace the entire roof unit at a reasonable cost. Plus, you will know for sure the problem is fixed because the entire unit is brand new.

For generator service and repairs, Onan dealers are easy to find. Most of them have been working on Onan generators on large RVs for years. They know their products and are pleasant to deal with.

 

[ATeam]

Sounds like if we see Phil in the desert we just need to go visit him and Diane.

Come on over! For large groups, we can fire up the reefer and party in back.

 

[greg334]

Phil,
It's great to hear about the floor insulation. I think the problem for many of us is using a sleeper (factory or after market) that uses the old style of insulating things, cheap foam, fiberglass matting, wood and so on. Some people don't understand the how much insulation matters in a truck, both cab and sleeper and even just insulating the roof and sides of the roof panel helps a lot.

About the generator, you did it right. I think the simplicity of your setup reflects the flexibility needed in a truck. Unlike the APU system, some of them are just copies of each other, the biggest issue I have seen is serviceability more than anything else.

I wonder what generator are they using that blows out bearing?

 

[MR.SNAPPY]

Come on over! For large groups, we can fire up the reefer and party in back.

Sounds like some of the partys I went to in my younger years

 

[arkjarhead]

Nobody was calling you a puss Phil. I was just telling you what others said it was like back in the day. Why do you stay on the defensive? No one can say anything to you without you snapping back. I know it's hard to tell people's emotions on this thing.

 

[pelicn]

Ark, I don't think Phil was being defensive, I think he was joking. At least that's the way I read his post.
You know, like, "Hey!, it's getting a little warm back here!" Check temp, Holy Cow! No wonder it's a little warm back here!


Now....about that "party in the reefer"...
Is this BYOD? (Bring your own Diesel)

 

[arkjarhead]

Well, if everybody pitched in a gallon we could probobly party for awhile.

 

[ATeam]

Ark, I don't think Phil was being defensive, I think he was joking. At least that's the way I read his post.
You know, like, "Hey!, it's getting a little warm back here!" Check temp, Holy Cow! No wonder it's a little warm back here!


Now....about that "party in the reefer"...
Is this BYOD? (Bring your own Diesel)

pelicn is correct. I was joking. Ahhh the limitations of print.

 

[arkjarhead]

Like my last sentence says, you can't tell people's emotions on this thing.