Coolant heating system ideas and help

[Maligator.]

So I sprung a coolant leak somewhere near the heater to the left of the drivers seat, I've had to take my entire switch panel apart trying to access the leak. More on that later as it's too cold right now for me to work on it. (I suspect loose clamps from some -30 weather on the trip up here, it's just still too cold for me to tear it all apart and troubleshoot the leaks).

So I've been wanting to plan a good coolant heating system that isn't going to take up too much space but still be a good source of heat.

Currently system is as follows: 35 foot front engine dognose DT466E, has 1 large leaking heater next to driver. 6 feet back from that is a booster pump, also possibly leaking. 3 feet back from the booster is the first passenger heater. The coolant tubes then run under the chassis to bypass an emergency exit door and about 15 feet back to a rear passenger heater.

Here are my thoughts:
Plan #1
Delete the rear 2 large, old passenger heaters and instead of looping the lines, install a webasto coolant/compartment heater in the spot where the first passenger heater was installed just before the emergency door so I don't have to run lines outside and can either patch those holes or use them for utilities later, perhaps the webasto exhaust. If I go this route, do I really need a booster pump and should I delete it also and just have: Drivers heater, 10 feet of coolant lines to webasto. Or keep the booster and why would you keep it?

Plan #2
Leave the first stock heater in place and have the webasto behind the emergency door.

In either plan I will have a separate Diesel heater in the back/bedroom area.

Also, any good ideas on getting a Combo webasto in Alaska without paying 300 for shipping?

Other miscellaneous Qs, when I tap my 100 gallon tank in the back of the bus, do I want to run the fuel line to the Webasto underneath the bus outside or inside for most of the run? I wouldn't say I'm in sub zero temps often and won't be, I also use anti-gel when temps dictate, is that bad for the webasto? Should i just use a separate diesel tank for webasto since it will be 15 or 20 feet from gas tank? Thanks in advance for any and all thoughts and assistance.

[s2mikon]

I don't know, you live in Alaska and you want to remove heaters? Remember as it gets colder outside the engine coolant also gets cooler even though you have a thermostat, and the remaining heaters become less effective. I would want to add the webasto to the existing system.

[Maligator.]

Originally Posted by s2mikon

I don't know, you live in Alaska and you want to remove heaters? Remember as it gets colder outside the engine coolant also gets cooler even though you have a thermostat, and the remaining heaters become less effective. I would want to add the webasto to the existing system.

We don't plan on living here when the bus is completed, gonna snowbird in October, come back Aprilish. My bus heaters are huge, 3 feet long, fills the entire space under a bus seat. I will always be able to run the 5k diesel heater in the back as well if i'm not running hot enough. On the way from Tok to Wasilla I ran with just the one drivers heater on and the interior of the bus was around 38 to 40 degrees when it was -20 out. I didn't know where i was leaking coolant so I shut off the back 2 heaters and pump. When I had them all on it was very warm in the bus, i'd guess low to upper 60s. I'd probably keep one somehow with the drivers heater and webasto but these huge heaters really put out. I understand I'll lose temperature in really cold weather but if it's -20 outside and 40 inside I'm very happy. We are comfortable with driving in 40 to 60 degree cabin temps. I will also hopefully be deleting a fair share of windows in the rear and doing a solid insulation job.
Thanks for making me think twice though and that's a very nice bus you have sir.

[DrDanger]

I am in the process of installing a Webasto Thermo Top C as we speak, so take what I say with a grain or two of salt. I'm trying to figure it out too. This is a great resource if you haven't already read it:https://www.skoolie.net/forums/f51/h...eat-19412.html
Anyway, here's my two cents...

Originally Posted by Maligator.

Plan #1
Delete the rear 2 large, old passenger heaters and instead of looping the lines, install a webasto coolant/compartment heater in the spot where the first passenger heater was installed just before the emergency door so I don't have to run lines outside and can either patch those holes or use them for utilities later, perhaps the webasto exhaust. If I go this route, do I really need a booster pump and should I delete it also and just have: Drivers heater, 10 feet of coolant lines to webasto. Or keep the booster and why would you keep it?

You wouldn't need a booster pump because the Webasto has a pump in it. So if you do that, is this front Webasto just used for engine pre-heat and running the driver/defrost heat?

Originally Posted by Maligator.

Plan #2
Leave the first stock heater in place and have the webasto behind the emergency door.

In either plan I will have a separate Diesel heater in the back/bedroom area.

Not sure about your layout, but it sounds like you could have one Webasto behind your emergency door provide all the heat you would need back there. There are alternative hydronic radiators other than the stock ones. I am not using one but other folks have.

Originally Posted by Maligator.

Other miscellaneous Qs, when I tap my 100 gallon tank in the back of the bus, do I want to run the fuel line to the Webasto underneath the bus outside or inside for most of the run? I wouldn't say I'm in sub zero temps often and won't be, I also use anti-gel when temps dictate, is that bad for the webasto? Should i just use a separate diesel tank for webasto since it will be 15 or 20 feet from gas tank?

If you can burn it in your engine you should be able to burn it in your Webasto. As far as the distance goes, my installation manual says the max suction length (from the tank to the pump) is 6'6" and the max delivery length (pump to Webasto) is 19'6" so you should be good there as well.


Good luck and have fun out there in the Valley. We used to live in Palmer.

[cadillackid]

The booster pump is just that a booster pump it really is designed to up coolant flow when idling or driving slow, I’ve found in my busses heater flow with the engine at speed is pretty good.

You should be able to take the lower panels of your driver heater off without the switch panel. I’ve had all mine apart ,

[Maligator.]

Originally Posted by cadillackid

The booster pump is just that a booster pump it really is designed to up coolant flow when idling or driving slow, I’ve found in my busses heater flow with the engine at speed is pretty good.

You should be able to take the lower panels of your driver heater off without the switch panel. I’ve had all mine apart ,

I have all the panels off but the coolant connections are in the back or towards the front of the dash, I've taken out all the screws but it still won't budge, do they glue or solder these things in? I literally have to move it like 6 inches to access but it's buggered and it's been between 10 and 0 for a while, that's not good for bare hand tinkering.

I'm gonna take out the electrical circuits I don't need in a couple months anyways so I don't mind breaking down the panel. Made a schematic and labeled everything first ofc.

I guess I misunderstood and thought there was a version of Webasto that also functioned as a heater itself but apparently you run the webasto and also your DC passenger heater(s) to circulate warmth in the cabin.

So I think I'll just delete the back heater and put the webasto in where i delete my booster pump, does that sound more feasible?

System: from engine to drivers heater > drivers heater to webasto where old leaking booster pump is > webasto to a forward passenger heater location to be determined.

I'll also have a diesel heater and wood stove. Considering hydronic webasto use after reading all your posts but that'll be a while so I have time to research. Thanks for the help and info!

[Maligator.]

DrDanger thank you, I did a lot of reading and understand it better. For some reason i thought there was a webasto that also doubled as a blower/radiator itself. Also, using it to run hydronics is very interesting so I'll be reading about this in the future.

[DrDanger]

Originally Posted by Maligator.

DrDanger thank you, I did a lot of reading and understand it better. For some reason i thought there was a webasto that also doubled as a blower/radiator itself. Also, using it to run hydronics is very interesting so I'll be reading about this in the future.

There are some models that blow air. In fact, I just discovered this: https://youtu.be/SbkpWYHy7vo

If I had seen this a year and a half ago I would have jumped all over it!

[Maligator.]

Originally Posted by DrDanger

There are some models that blow air. In fact, I just discovered this: https://youtu.be/SbkpWYHy7vo

If I had seen this a year and a half ago I would have jumped all over it!

Wait, so that's a coolant heater too? So it does blow hot air, domestic hot water and coolant heating?

Or is that hot air and hydronic? Their diagrams in the video weren't very clear lol

[DrDanger]

Originally Posted by Maligator.

Wait, so that's a coolant heater too? So it does blow hot air, domestic hot water and coolant heating?

Or is that hot air and hydronic? Their diagrams in the video weren't very clear lol

It looked like just domestic hot water from the video. I guess if you really wanted to heat coolant with it too you could have a heat exchanger between the domestic hot water and coolant (at which point you could use that booster pump as a circulation pump for the coolant)

[Ronnie]

The wabasto in my shorty heats the coolant and has a pump for the coolant next to it to circulate it. This is factory installed on a 99 amtran. This bus is far from useable, so I have not tried it.



There is a Wabasto hot air heater, and a Chinese knock off. Seems like the air heater might be better suited to go in place of your rear heater?

[Maligator.]

Originally Posted by Ronnie

The wabasto in my shorty heats the coolant and has a pump for the coolant next to it to circulate it. This is factory installed on a 99 amtran. This bus is far from useable, so I have not tried it.



There is a Wabasto hot air heater, and a Chinese knock off. Seems like the air heater might be better suited to go in place of your rear heater?

I have a chinese knock off diesel heater that just does Air and I'm planning on putting that in the bedroom til it bites the dust then i'll upgrade to a non-knock off. What i'd really like is a 3 way diesel heater that does Air/domestic water/coolant.

As DrDanger pointed out, I can likely get this through a heat exchanger between the Webasto Dual. However, I don't know if the Dual is meant to produce that much heat over a sustained time (make sense?) So the Dual has coils in it that heat domestic water and a fan that blows air over the coils.

Maybe I should just ask this, has anyone used a Webasto Dual as a coolant heater using an add-on heat exchanger and pump? Does this require Arduino or Pi or could I use a switch controlled valve or something simple?

I guess I'll just ask, is there a version of diesel heater I haven't found that will do 1) Blown hot air and 2) Engine coolant heat? If so I could easily get my hot water from a coolant to water heat exchanger place appropriately.