We'll be using this mostly in the 3 seasons not Winter, but we hope to take some spring break trips as well. So heat is a thing we'll want to have.
I've used the OTR heat and it works great. I've thought of using Propane (I'm planning on having propane Range and 2 Way Fridge as well) and having that work in the ducting that is there. Attached is the current state of the floor.
If they kept the same design, the OTR heat runs off the engine system. You need that.
That said, if you remove the plywood that is now at grade with the ducts, you'll find a nasty dusty greasy...mess under that plywood. You'll want to clean it.
I still have my OTR system and I don't think I could survive in the summer without the OTR air. It is the only way to provide AC to the driver, and I have 3 roof units :)
Anyway, welcome! This is a great place for information and the folks here are the best.
My OTR Air was removed by some previous owner.
I've thought of putting it back in there, but in talking with Grumpy, he said he'd do roof airs if he had it to do over again, but that was vs basement air I think, he has OTR air as well.
I was hoping to get away with 2 woof airs, I was going to tackle that in another post. I've done a ton of research, but I have a list of about a dozen questions :-) . I'm just trying not to flood the board.
Quote from: neoneddy on April 27, 2017, 01:33:29 PM... So heat is a thing we'll want to have. I've thought of using Propane ... and having that work in the ducting that is there.
Can't talk about the state of your floor (if I did that, I'd be standing on concrete ... been there), but usually the biggest thing about a combo heat (or AC) system is unifying the two different parts of the system. If you're going to keep vents and ducts, you'll probably want to keep the stock heat exchangers and fans for when you're moving down the road, but doing a bifurcated system with an add-on propane heater for when you're parked should work just fine. I would want to have some kind of diverter or blend door so that the production of air from one source would be properly directed so as to not "bleed off" through the inactive unit ... but that's just me, I guess.
Quote from: daddysgirl on April 27, 2017, 01:58:43 PM... I still have my OTR system and I don't think I could survive in the summer without the OTR air. It is the only way to provide AC to the driver, and I have 3 roof units :)
Again, you would have to have two different A/C systems. That's also not fatal -- what has proven to be fatal for many people is having to spend thousands of $$$ over a couple of years trying to nurse a 30-year old OTR A/C system along and still have something that's not dependable -- yeah, many people. If you can keep a OTR A/C going, that's good but I'd never depend on it. (What you can depend on is that any unreliable system will crap out in the worst place at the worst time.)
If I had three roof tops and couldn't keep the driver cool, I'd want to know what was wrong with them but maybe there are some buses and some conditions where three -- installed in the best place and with the best installation -- wouldn't be enough. I dunno.
Quote from: daddysgirl on April 27, 2017, 01:58:43 PMAnyway, welcome! This is a great place for information and the folks here are the best.
Big agree on that.
Quote from: neoneddy on April 27, 2017, 04:17:12 PMMy OTR Air was removed by some previous owner.
That ends that subject right there. It would double your budget to replace it, that is, if you had a BIG budget, it would double it to replace it.
Quote from: neoneddy on April 27, 2017, 04:17:12 PMI was hoping to get away with 2 woof airs, I was going to tackle that in another post. I've done a ton of research, but I have a list of about a dozen questions :-) . I'm just trying not to flood the board.
What some people have done is put a regular car compressor on the engine, run piping to a receiver dryer, install a dash system for the driver and put 2-3 roof tops up ("technologically dense" as Mazda's rotary wizard used to say, and somewhat expensive, but it is the best way for some people. Other people are in places where they need 4-5 roof tops when they're parked, and they work for the time they're on the road. How do you run an A/C system? Some people have enough juice out of a big oil-cooled alternator through an inverter, others run their gen set running down the road.
As you can see, a lot depends on your bus (insulation, number/types of windows, layout of floor, size of windshield, amount of heat from engine and underfloor, amount of hot[or cold]-outside-air ingress, etc.). You gotta figure out what you need and design a way to take care of that.
HI;
If your OTR heat is working, keep it! You will need to do something
else when parked.
Merle
Everything Bruce and Merle said...
BUT...pull out that top layer of plywood. You need to clean that channel regardless of your choice of heat. You will be surprised by what's there...but don't be. It will come out.
The reason my front AC doesn't cool the driver is the windshield and the insulation. The latter I am doing now, starting in the back. The former is what it is, although I will make a couple of modifications.
My OTR AC is wonderful...never failed me. It's been converted to 134A...but it will freeze me out when it's on. That said, I have been thinking of a smaller unit. I just haven't decided yet. I'm still tearing out and working in the rear ::)
Quote from: daddysgirl on April 28, 2017, 05:21:55 AM
The reason my front AC doesn't cool the driver is the windshield...
Andrea, You might look into newer window films and tinting product from XPEL (XR or CS) or others. They have a SPF of 1000 or so. I had all my 25 yo window tint replaced with them and we noticed the difference in the Texas heat immediately. I also had the front windshield done and it really made a difference. It has only 5% shading, but still has the SPF 1000 protection. Just a thought...
Quote from: Astro on April 28, 2017, 07:30:39 AM
Andrea, You might look into newer window films and tinting product from XPEL (XR or CS) or others. They have a SPF of 1000 or so. I had all my 25 yo window tint replaced with them and we noticed the difference in the Texas heat immediately. I also had the front windshield done and it really made a difference. It has only 5% shading, but still has the SPF 1000 protection. Just a thought...
Oh yes...I am planning on adding some sunscreen. I need to make sure I don't run afoul of VA law in the process. They are funny about that stuff here.
The year after dad passed, I took mom to a bluegrass festival in NC. 5.2 hours driving into the sun on the way home...with the world's worst hangover...and I don't get hangovers :) When we got home, I had actual tan lines all over the front. I couldn't believe it.
.
Quote from: daddysgirl on April 28, 2017, 08:34:00 AM
Oh yes...I am planning on adding some sunscreen. I need to make sure I don't run afoul of VA law in the process. They are funny about that stuff here.
The year after dad passed, I took mom to a bluegrass festival in NC. 5.2 hours driving into the sun on the way home...with the world's worst hangover...and I don't get hangovers :) When we got home, I had actual tan lines all over the front. I couldn't believe it.
.
Tan lines. The new window glass is UV resistant so you can't get tanned through the windshield anymore. A downside to this is if you wear prescription glasses with auto-darkening they won't get dark.
As far as OTR heat, you must keep the copper lines going to the front for the defroster and driver's heat. I don't know why it hasn't been mentioned yet, but a 45k btu Webasto diesel-fired heater can be plumbed into those existing heater lines and with some heater boxes integrated into the interior off those lines you have the best camping heating system. You can also plumb for floor heat with the Webasto or Esbar heater.
--Geoff
Quote from: neoneddy on April 27, 2017, 04:17:12 PM
My OTR Air was removed by some previous owner.
I've thought of putting it back in there, but in talking with Grumpy, he said he'd do roof airs if he had it to do over again, but that was vs basement air I think, he has OTR air as well.
I was hoping to get away with 2 woof airs, I was going to tackle that in another post. I've done a ton of research, but I have a list of about a dozen questions :-) . I'm just trying not to flood the board.
You need to remember that without OTR heat ,you will have to depend on a couple of small fans up front for your defrosting which will drive you nuts .On you AC units ,i can tell you that these roof mounts are not what the used to be .I had my three RM's replaced with three made in China Dometics and I can tell you ,these are a sorry excuse for AC units .WE haven ran them except while parked ,but I can't see these three units keeping this coach cool. Have two Colman's on a 22 year old motor home that cools way better than these dometics do.
Hi Andrea, I put 3 units on my 40'er, on the front unit in the living room, I put the AC closer to the driver, then took 90 degree aluminium foil 1 1/2" ducts and attached them to the side vents of the drop down style AC, when I'm driving the 15K unit is enough to keep me and her cool, I run the center AC also, on days over 100°, but then I'm from LV, so i might be more tolerant of heat, lvmci...
Ed -
If your OTR heat works, keep it.
My OTR A/C doesn't work, and the two roof A/Cs can barely keep my 35' MCI cool on a 90o day
But the OTR heat keeps us toasty going down the road in temps down to below freezing, and, of course, the defroster works wonderfully. It's especially nice on those cool mornings in the upper 40's - mid 50s to keep the chill off inside as the day warms up.
Geoff's comment is an excellent suggestion - best of both worlds! Engine heat going down the road, Webasto or Espar when parked.
FWIW & HTH. . .
;)
Quote from: Geoff on April 28, 2017, 09:16:45 AM
Tan lines. The new window glass is UV resistant so you can't get tanned through the windshield anymore. A downside to this is if you wear prescription glasses with auto-darkening they won't get dark.
As far as OTR heat, you must keep the copper lines going to the front for the defroster and driver's heat. I don't know why it hasn't been mentioned yet, but a 45k btu Webasto diesel-fired heater can be plumbed into those existing heater lines and with some heater boxes integrated into the interior off those lines you have the best camping heating system. You can also plumb for floor heat with the Webasto or Esbar heater.
--Geoff They have glasses now that will get dark inside a vehicle .Got mine at Sam's,but I will say this .If you see a tunnel in your future you better lose these things in a hurry ,lol
Quote from: lvmci on April 28, 2017, 01:27:58 PM
Hi Andrea, I put 3 units on my 40'er, on the front unit in the living room, I put the AC closer to the driver, then took 90 degree aluminium foil 1 1/2" ducts and attached them to the side vents of the drop down style AC, when I'm driving the 15K unit is enough to keep me and her cool, I run the center AC also, on days over 100°, but then I'm from LV, so i might be more tolerant of heat, lvmci...
I have 3 units also, the front unit is just past the hump on the MC8...maybe 3-4 feet from the front. I started in the rear, but the front AC needs attention, and I'm tearing down the ceiling while I'm at it.
Question... Did you duct the front roof top air? or do you have an additional unit? My OTR is still fully functional, but I want to plan a backup now...while I've got her torn down. I could easily run 1 1/2" ducts on the ceiling...just looking for clarification :)
And BTW...I really appreciate your suggestions. Really...Thank you.
Geoff...My windshields are in perfect shape. I can't justify replacing them, but I sure as heck can justify the most shading I can legally pull off :)
I removed the entire over the road heating and A/C system. What was odd was the A/C evaporator was installed with some plumbing, but nothing else was installed since my transit bus was an Portland, Or bus. I removed the heater coil which is huge-6ft X 18" X 5" deep. Had it pressure tested and reinstalled it lengthwise in my hallway with 4 vents and 2- 14" radiator fans pushing the heat out. The controls are by the front seat and I can turn it on, count to 10 and feel the heat. Truly an amazing amount of heat comes out. Good Luck, TomC
Quote from: TomC on April 29, 2017, 10:13:14 AM
I removed the entire over the road heating and A/C system. What was odd was the A/C evaporator was installed with some plumbing, but nothing else was installed since my transit bus was an Portland, Or bus. I removed the heater coil which is huge-6ft X 18" X 5" deep. Had it pressure tested and reinstalled it lengthwise in my hallway with 4 vents and 2- 14" radiator fans pushing the heat out. The controls are by the front seat and I can turn it on, count to 10 and feel the heat. Truly an amazing amount of heat comes out. Good Luck, TomC
Tom, what are you doing for a defroster?
Hi Andrea,the front escape hatch towards the front of it, is where i put the traditiinal roof top, down draft manual style AC unit. B &B uses the 6" wide 1 1/2" Thick right angle ducts just as an experiment, worked so well, I kept it. In the future I will drop the ceiling and finish the duct work to deliver to the driver & passenger seats with registers, in the mean time you can open and close the registers to accommodate using the living room or driving, but the windshield area needs the most cooling , lvmci...
Geoff-I have a T with ball valve to shut off the big heater core. The front defroster is still hooked up and have a ball valve on that too to control the heat. Works well-practically never have to kick on the fan-just the air pressure from outside moves enough air through when heat is needed. Good Luck, TomC
Quote from: lvmci on May 01, 2017, 07:30:42 PM
Hi Andrea,the front escape hatch towards the front of it, is where i put the traditiinal roof top, down draft manual style AC unit. B &B uses the 6" wide 1 1/2" Thick right angle ducts just as an experiment, worked so well, I kept it. In the future I will drop the ceiling and finish the duct work to deliver to the driver & passenger seats with registers, in the mean time you can open and close the registers to accommodate using the living room or driving, but the windshield area needs the most cooling , lvmci...
That is so awesome! Thank you so much for the idea.
And just to run this thought by someone who has done it...
When I take the front ceiling down to insulate it (like the back) I will run ductwork (attached to the roof on the inside) from the existing front discharge vents over towards the front, and route ductwork from the rear discharge vent along the other side and have the outlet closer to the passenger side.
I never had a front escape hatch, but the front roof unit is already there. Also, I have just about twice the number of roof supports than most MC8's. They removed many of them when designing units built after # 31706. Maybe it was a cost issue, but I have plenty of ways to attach the vents.
Thanks again...simple and genius. ;D
Both my coaches had their OTR heat removed. Literally my biggest regret. Keep it. Trust me. On those frigid drives, you'll be sooop thankful for the free high BTU heat.
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