OTR heat if you remove the bus system ?
 

OTR heat if you remove the bus system ?

Started by someguy, August 15, 2020, 11:06:54 AM

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someguy

How do people heat a bus when traveling in winter if they remove the stock passenger area evaporator and heating coil and circulating blowers ?

lostagain

Don't remove it. Besides, defrosters are necessary, and required by law.

We heat going down the road with a combination of the OTR heating system, the propane furnace, radiant propane heaters (Mr Heater), electric cube heaters, and the Webasto I installed last fall that preheats the engine and the generator, and heats the basement bays.  When it is 20 below driving South from Canada in January, you need all of the above...

I think the ideal coach is all diesel: Webasto or Aquahot type diesel heater that preheats the engine, heats upstairs and downstairs with in-floor heat or heat exchangers, heats the domestic water, and whatever else you like. And a good diesel generator. Solar panels are nice, but they don't work in a snow storm in January.
JC
Blackie AB
1977 MC5C, 6V92/HT740 (sold)
2007 Country Coach Magna, Cummins ISX (sold)

buswarrior

What anyone in a northern state or Canada calls "winter" and driving down the road is a demanding condition.

As far as a Canadian is concerned, there really isn't a decent alternative to the stock coach heating system for going down the road.

The cold creeps through the walls and windows, the stock system is specifically designed to keep the coach warm from the edges in. Any replacement system will fail, as the heat is not typically delivered to the walls and windows, the way the stock system does.

The total bullshit that busnut wives have to put up with, freezing their asses off inside the coach, while the idiot male is up front toasty with the defroster, after tearing out the rest...

Grounds for divorce, and she won't want the bus in the settlement...

The stock AC is lovely, but not necessary, the stock heat anywhere on the continent that it gets cold,  a must have.

Happy coaching!
Buswarrior
Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

someguy

Quote from: lostagain on August 15, 2020, 11:45:53 AM
Don't remove it. Besides, defrosters are necessary, and required by law.

I would obviously keep the dash heat/defrost in tact.  But almost all the bus conversions I've seen remove the OTR A/C system, including the blowers and also block off the air ducting in the bus.

QuoteWe heat going down the road with a combination of the OTR heating system, the propane furnace, radiant propane heaters (Mr Heater), electric cube heaters, and the Webasto I installed last fall that preheats the engine and the generator, and heats the basement bays.  When it is 20 below driving South from Canada in January, you need all of the above... 

Why is that ?  Why isn't the bus heat system alone enough in your MCI 5?   How would an E/J4500 be different ?

QuoteI think the ideal coach is all diesel: Webasto or Aquahot type diesel heater that preheats the engine, heats upstairs and downstairs with in-floor heat or heat exchangers, heats the domestic water, and whatever else you like.

I agree.  Tie engine coolant heat into the house heat system with a heat exchanger ?  Put heat into the house with fan coils and a heated floor ?

QuoteAnd a good diesel generator. Solar panels are nice, but they don't work in a snow storm in January.

Agreed.

someguy

Quote from: buswarrior on August 15, 2020, 03:41:54 PM
What anyone in a northern state or Canada calls "winter" and driving down the road is a demanding condition.

As far as a Canadian is concerned, there really isn't a decent alternative to the stock coach heating system for going down the road.

OK.

QuoteThe cold creeps through the walls and windows, the stock system is specifically designed to keep the coach warm from the edges in. Any replacement system will fail, as the heat is not typically delivered to the walls and windows, the way the stock system does.

I kind of agree with you.  So try to keep the stock circulation system intact.   But modify it so that it works when stationary and without the engine running.

If I use the stock evaporator, won't the stock blowers take a lot of power to turn when dry camping? 

QuoteThe total bullshit that busnut wives have to put up with, freezing their asses off inside the coach, while the idiot male is up front toasty with the defroster, after tearing out the rest...

Grounds for divorce, and she won't want the bus in the settlement...
LOL.

QuoteThe stock AC is lovely, but not necessary, the stock heat anywhere on the continent that it gets cold,  a must have.

Glad I asked.  Thanks for the advice.

lostagain

The OTR heating system was mostly removed by the converter in 1989. The only thing left is a heat exchanger in the bedroom, and one just behind the driver's seat, and the defrosters. So driving in 20 below, the propane furnace is on, and if my wife is riding with me, she needs an electric cube heater in front of her that runs off the inverter. Both our front seats have electric heat. I also carry 2 or 3 propane heater for back up, and to put in the bays overnight. Although now with the Webasto, I don't use them so much. Good to have for redundancy. You need to be prepared and ready for boondocking overnight in cold weather with 1500 miles to go till you see warm enough weather...
JC
Blackie AB
1977 MC5C, 6V92/HT740 (sold)
2007 Country Coach Magna, Cummins ISX (sold)

buswarrior

My old mc8 was set up with a big webasto in-line to the stock heat exchanger.

The stock fans were enabled when plugged in to shore power or generator running.

It was possible to get interior too hot for comfort, if you set the stock temp control to max, in sub zero, with outside air intake open... burning 100 000 btu worth of diesel.

A simple bypass wire to the fan control will do it.

Not efficient, but mother NEVER complained about being cold...

Not the way to set-up a camper, the bus had been a mobile classroom before i got it.

Radiant heat is the way to reduce power consumption, no fans, just the pumps and the boiler.

Nobody complains about too much heating capacity... not enough and you are a failure...

Happy coaching!
Buswarrior

Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

richard5933

You'll need to learn one word...redundancy.

Having redundant systems is nearly always a requirement in certain areas. You will have redundant electrical systems - one for use while driving down the road powered off the bus engine, and a totally separate one for use while plugged in or on generator.

Many have redundant a/c systems - like us we have one a/c system (the factory OTR system) for going down the road, and a totally separate system for when we're at a campground.

For heat, we have three systems - the factory OTR system using the heater core for going down the road, and for use while stationary we have electric if we're plugged in and we have propane for when we are dry camping.

Neither of our two heating systems we use while camping will ever keep up with things while we're going down the road. There are just too many ways for air to infiltrate the bus for them to keep up. They do fine with us standing still, but the 60-70 mph cold air finds its way inside.

Many have redundant ways to make hot water - propane, electric, and maybe even with an engine heat exchange coil.

You can pull the stock heater core and fans if you leave the lines to the defroster. The defroster will keep the front few feet of the bus somewhat comfortable, more so if you have a curtain behind the cockpit area. The rest of the bus will depend on what you have back there for heat.

Since you don't have a bus yet, it would be a good idea to wait until you know the condition of the equipment before making decisions. For example, both of my buses have had fully functional OTR a/c and heat. It didn't take much to get our current bus's a/c repaired when the compressor went out, and it's been doing find since with no other problems. Same for the heat - it will keep us toasty. If you end up with a bus with working systems you'll have a totally different plan of attack than if you find a bus where the systems are in need of extensive work.
Richard
1974 GMC P8M4108a-125 Custom Coach "Land Cruiser" (Sold)
1964 GM PD4106-2412 (Former Bus)
1994 Airstream Excella 25-ft w/ 1999 Suburban 2500
Located in beautiful Wisconsin

buswarrior

Often overlooked...

Screw around all you want, when the temp is 100, to get it down to 70, is just 30 degrees...

You've got to have your wits about you to get from zero to 70...

Totally different game... and often, a loser's game, when it comes to busnuts...

Happy coaching!
Buswarrior
Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

dtcerrato

Quote from: buswarrior on August 15, 2020, 06:24:37 PM
Often overlooked...

Screw around all you want, when the temp is 100, to get it down to 70, is just 30 degrees...

You've got to have your wits about you to get from zero to 70...

Totally different game... and often, a loser's game, when it comes to busnuts...

Happy coaching!
Buswarrior

When it's 100 outside we're great at 85. Only one roof air is all we ever needed. 
Dan & Sandy
North Central Florida
PD4104-129 since 1979
Toads: 2009 Jeep GC Limited 4X4 5.7L Hemi
             2008 GMC Envoy SLT 4x4 4.2L IL Vortec

Jim Blackwood

85 in the East without a breeze is sorta sticky. Not many people are comfortable that way, what with the high humidity. So the AC demands might be a little higher. But I think we've now reached a sort of conclusion that around 3-4 tons will get the job done when stationary. Shading the roof with solar cells could help a lot. How you get that is up to you, and OTR is a different matter. I've been thinking that a pair of 18K sealed compressors parallel to the engine driven Carrier pump could do it.

But on the heat since you're talking about buses newer than most here have, it is most likely to come equipped with a Webasto or Eiberspacher aux heater of around 80-90K btu capacity. In most cases that is going to be enough to keep the coach toasty warm and also heat the engine to operating temperature, which is its intended function. However with a little re-plumbing you can isolate the coach from the engine and heat just one or the other and then there is more than enough heat for the coach under just about any situation I would think. That is my primary plan for heat. Then supplement it with a propane fired furnace. You could add radiant, space heaters, baseboard units, floor cables, or anything else you want to run from your shore line. But by and large generators tend to be noisy so a good neighbor avoids running one. Just my thoughts but I agree, get the bus and then you can sort out just what you will need.

Jim
I saw it on the Internet. It MUST be true...

ccbmster

We almost never hang around where it is lower than 30-40 degrees for length of time.
I have two heat pump mini splits and a Mr. Buddy propane heater.  I also have a standard propane RV furnace, but I haven't had to turn it on since I don't remember when.
86 MCI 102A3  Travel MI, IN, OH, VA, KY, GA, FL, and OK with most time spent in GA and FL 6V92 with Allison 740 Automatic

someguy

Quote from: Jim Blackwood on August 16, 2020, 09:15:24 AM
OTR is a different matter. I've been thinking that a pair of 18K sealed compressors parallel to the engine driven Carrier pump could do it.

Are you saying that the stock OTR A/C in an E/J4500 wouldn't be enough to keep the coach cool when driving in hot weather ???

QuoteBut on the heat since you're talking about buses newer than most here have, it is most likely to come equipped with a Webasto or Eiberspacher aux heater of around 80-90K btu capacity. In most cases that is going to be enough to keep the coach toasty warm and also heat the engine to operating temperature, which is its intended function. However with a little re-plumbing you can isolate the coach from the engine and heat just one or the other and then there is more than enough heat for the coach under just about any situation I would think. That is my primary plan for heat.

I didn't realize those heaters put out that much heat.  I thought they were 20,000 BTU.

Let's say the bus I purchase has a high output engine heater.   How does one transfer the heat from the coolant to the air in the bus.  First off, with a heat exchanger, so that the bus doesn't need to have engine coolant circulating through the living space.   But then what ?   Use the stock fan coil ?

QuoteThen supplement it with a propane fired furnace. You could add radiant, space heaters, baseboard units, floor cables, or anything else you want to run from your shore line.

90,000 BTU is enough to heat a medium sized house in Canada in the dead of winter.  You need to supplement that ?

How does the heat system work on a Marathon or Featherlight coach ?

I'm an avid skier.   I want a full 4 season coach.  I want to boondock at a ski resort and spend the night toasty warm.


richard5933

As much as I enjoy innovation and encourage people to try new things, there's something to be said for tried and true methods.

Sometimes the answer to "why doesn't anyone do xxx?" is because no one has thought of it yet. Or no one has figured out how to make it economically viable. Or,...

Sometimes the answer is simply it's no better than the current, tried and true, method.
Richard
1974 GMC P8M4108a-125 Custom Coach "Land Cruiser" (Sold)
1964 GM PD4106-2412 (Former Bus)
1994 Airstream Excella 25-ft w/ 1999 Suburban 2500
Located in beautiful Wisconsin

buswarrior

One must check which aux heater is installed in any particular coach.

It could be anything... previous owners cannot be trusted to spend money on correct replacements... what market was it originally bought for?

The re-plumbing involved almost suggests removing it from the engine room and putting it midships somewhere more convenient.

They are plumbed parallel to the engine/stock heater, not in-line... getting stuff isolated, not creating feedback loops that will overheat the engine, directing the heat where you want it...

I am still scratching my head as to which way to execute this project.

For a ski bunny coacha big decision is whether you will run the generator overnight or not. Available power, dictates radiant or fan forced heat exchangers.

Happy coaching!
Buswarrior
Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift