Need some advice on webasto, air, coolant heat

Surf44

2002 Thomas 5.9l 24V Cummins Allison 2000
Joined
Mar 30, 2019
Posts
45
Location
Boise ID
Just bought myself a 2002 Freightliner 5.9 24v with the allison 2000 transmission. Just for background I am a full time sprinter van builder, Launch Vans in Boise, ID if you're interested, but that said a 2002 bus is a whole different animal than a brand new sprinter!

Right now I just am starting to gut the interior, planning on doing a somewhat overland style build since I don't have too much room for nice bathroom and full size kitchen.

So these are the questions I have of now for gutting and would really appreciate advice or just your opinion on the matter

I have a rear A/C unit, I'm wondering if I should keep it. Do you think that would be sufficient as the only a/c unit? I mean I've never had A/C in my van and last couple years been camping in just a roof top tent, to me the A/C on more of a travel/weekend warrior rig is for emergency where I could at least start the bus and let it idle if were really dying.

Also on the HVAC topic I have what seems to be normal bus engine coolant rear heat set up which I think I plan on removing. And I also have a Webasto heater tied into the coolant lines too. Is the webasto just for block heating? I was planning on putting an Espar air heater in anyways but if I could leave the heater already in there and it would work off the webasto that would be really cool!

The webasto is not working, I have not had a chance to diagnose it at all but the screen just doesn't turn on, not sure if someone can point me in a direction on where to start looking and testing.

Some pics for reference

IMG_3735.jpeg
IMG_3738.jpeg
IMG_3703.jpeg
 
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The A/C units on my bus were HUGE compared to a passenger car. They are meant to cool several people, and one in your short bus will probably cool better than you need. Unless you're hauling 25 people...
 
Not going to haul anyone, going to be a conversion. Do you think it’s over kill?

Another thing I’ve been thinking, is there a way to convert the compressor to run off say 110v vs the engine. 12v or mini splits aren’t cheap and if I already have an a/c that could ice box this thing I would like to keep it
 
I kept both engine driven air conditioning units, 24’ interior. On the road in 100-110 degrees, six kids and two adults. One unit with a curtain behind driver, will keep driver- up front cool. I actually have four air conditioners. Two engine driven and two rv type roof top 110v-120v units for use when parked. I have a big Webasto coolant heater for winter. I added a couple of valves to keep inside warm and not spend all the energy heating engine, and radiator. I also have programmable timer. I can set the timer, and when I go to start the bus, engine and heaters are already hot and ready to defrost and warm the bus.

William
 
I kept both engine driven air conditioning units, 24’ interior. On the road in 100-110 degrees, six kids and two adults. One unit with a curtain behind driver, will keep driver- up front cool. I actually have four air conditioners. Two engine driven and two rv type roof top 110v-120v units for use when parked. I have a big Webasto coolant heater for winter. I added a couple of valves to keep inside warm and not spend all the energy heating engine, and radiator. I also have programmable timer. I can set the timer, and when I go to start the bus, engine and heaters are already hot and ready to defrost and warm the bus.

William
Do you have some pics of how you built around the A/C units. I don't know how I like the size of the unit and that I can only use it while the engine is running. Really contemplating if a mini split is the way to go. I don't see why you couldn't have the mini split running while driving??

I was able to get the webasto running it also has the programable controller. I am now thinking that I could have the webasto and the heater fans ran off the eventually house batteries and that would be my heat right there for inside and engine for engine running or not
 
It depends on how much you will need AC. We weren't born with AC but it sure is nice to have. I don't ever remember AC being on any bus when I was going to grade school but we didn't have school in the Summer.

I had two AC units and removed them both. Part of me wanted to keep them especially after reading cadillackid's posts on how well they can work. I had already removed mine though at that point and there was no going back. If I had to do it all over again I'd try to keep the AC in the bus for driving. What you might do is get the AC working and see how well it works. You can always remove it later. Putting it back in will be more difficult.

Now I have a minisplit in the back. If it gets too hot up front I will put a smaller minisplit up front.
 
My hang up is how do I continue to gut the inside with leaving the a/c or heat.

Which brings me to some new questions after getting some of the ceiling planels down and getting a better idea of how I plan to build it.

What is usually the best plan with the back windows and emergency door windows? Are they pretty prone to leaking? I’m going to be removing and sheeting over all of the side windows and not sure if the rears should go too?
 
In my case, I left the ceilings and walls alone. Think something like a padded room. I use more like a really big van. I don’t live in it. It is a means of moving 8 kids and two adults, first. Rolling bathroom, second. Most of the people are girls/women. Then food, shower, camp site. Sometimes we get a hotel room and I will sleep in the bus with some of the kids, and my wife sleeps in the hotel room. Everyone uses pool, shower, and when possible washer and dryer for clothes.

William
 
Just bought myself a 2002 Freightliner 5.9 24v with the allison 2000 transmission. Just for background I am a full time sprinter van builder, Launch Vans in Boise, ID if you're interested, but that said a 2002 bus is a whole different animal than a brand new sprinter!

Right now I just am starting to gut the interior, planning on doing a somewhat overland style build since I don't have too much room for nice bathroom and full size kitchen.

So these are the questions I have of now for gutting and would really appreciate advice or just your opinion on the matter

I have a rear A/C unit, I'm wondering if I should keep it. Do you think that would be sufficient as the only a/c unit? I mean I've never had A/C in my van and last couple years been camping in just a roof top tent, to me the A/C on more of a travel/weekend warrior rig is for emergency where I could at least start the bus and let it idle if were really dying.

Also on the HVAC topic I have what seems to be normal bus engine coolant rear heat set up which I think I plan on removing. And I also have a Webasto heater tied into the coolant lines too. Is the webasto just for block heating? I was planning on putting an Espar air heater in anyways but if I could leave the heater already in there and it would work off the webasto that would be really cool!

The webasto is not working, I have not had a chance to diagnose it at all but the screen just doesn't turn on, not sure if someone can point me in a direction on where to start looking and testing.

Some pics for reference

View attachment 980840View attachment 980841View attachment 980842
Nice Shorty!
 
I have a 30' FS65 It never had A/C. I put in a 9000 BTU minisplit heat pump. It is mounted above the front window and the outside unit is under the bus on the driver's side. I can run it all day long on solar and still charge the batteries on a sunny 90 degree day and it can get the bus down to the low 60 degrees. But a 12000 BTU would be able to cool it down quicker. In your bus a 9000BTU minisplit would be more than enough if you have insulation. I also have an Eberspacher hydronic heater. I plumbed 4 heat loops with it controlled with zone valves. I didn't want to have the house heating system tied to the chassis so that if one or the other went down I had the other still working. It works well when the pump turns on but it is prone to getting stuck with the smallest of debris in the heat transfer fluid. I added a spin on coolant filter inline and it has helped. Due to that I would not recommend the that brand.
 
My hang up is how do I continue to gut the inside with leaving the a/c or heat.

Which brings me to some new questions after getting some of the ceiling planels down and getting a better idea of how I plan to build it.

What is usually the best plan with the back windows and emergency door windows? Are they pretty prone to leaking? I’m going to be removing and sheeting over all of the side windows and not sure if the rears should go too?


I removed the heat from mine. I didn't want engine coolant running around inside the bus. There was another thread recently talking about just this on how to build the bus to keep the coolant lines for the heater. You have to make sure they are accessible for maintenance.
 
I decided I'm removing the rear heat and I'll keep the webasto for heating the front and engine. Not sure about the Air conditioner yet it was finally a warm day here in Boise and holy smokes even mounted in the back that a/c kept it pretty nice driving in a totally gutted interior. But the size and having the engine running is probably going to kill the idea of keeping it.

Do you think theres a good value for trying to resell it on like marketplace?

Also with the compressor on it's own belt and mounted on top of the engine, could I swap the compressor for a air compressor? Would that be worth it or just get a regular undermount compressor like you would put on an overland/van build?
 
Those AC units are supposed to work really well. That is why cadillackid suggests to keep them. It's Summer here for half the year so a lot more useful than someplace like where you are. Do you plan on driving South in the Summer?

My bus which is just a tad bit longer than yours at 28 foot had two AC compressors. I was going to put an air compressor on one and a secondary alternator in the other place. I've yet to do either yet but those are some ideas.

You may only be seeing half of the AC unit. Mine had an inside unit and an outside unit. My outside unit was under the side of the bus.

I have my 12k minisplit running today. It's 86 degrees outside and with the bus in the sun I could only keep the bus at 81 degrees. An hour after I turned the AC off the bus went to 122 degrees inside. I still need to insulate the roof but that at least gives you some idea of what you are working with. Maybe take a few weeks to think about what you want to do. Let it get real hot outside there and then start the bus up and see how quickly that AC cools it down.
 
Keep the AC for as long as you can during your build. Sooooo many folks have come to regret ripping it out.

Mine is in the back, where the bed it. I wouldn't give it up for anything (I live in California where it gets hot).
 
And, by the way, carefully think through the emergency egress window deletes. RVs and these conversions go up like a roman candle and you wouldn't want your last thoughts to be 'gee I could use that window now'.
I relocated my EE windows to the rear where we sleep, so there are a couple of escape options.
 
Keep the AC for as long as you can during your build. Sooooo many folks have come to regret ripping it out.

Mine is in the back, where the bed it. I wouldn't give it up for anything (I live in California where it gets hot).
Do you have some pics of how you incorporated it into your build?
 
Thanks, I like how you painted it to blend more. I plan on doing cedar on the roof and I would have to take it down somehow anyways to get those ceiling panels off. I just am having a hard time deleting a air conditioner that probably cost $10k and friggin blows ice cold!

Has anyone taken the compressor off the engine and ran it off of a 110v motor?
 
I really like that idea about the compressor. You could build a housing under the side of the bus and put an electric motor under there to turn the compressor.

There's a bunch of relays/etc that control that compressor and AC in the wiring panel. You might take note of that as well. Mine had three relays for each AC unit (one for each level low, medium, high). .

Look behind the wall or under the bus to see what is coming up and into that unit. That way you can see what you will need to address in order to take it down to remove the ceiling.
 

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