Webasto 90S

[inhof009]

I'm on the search for a coolant heater for a hydronic floor system, and I came across someone offering a used webasto 90S for $450, including an expansion tank, heat exchanger, etc.

Looks like a great system and sweet deal, BTUs are good for me, but the problem is this one is 24V and I have only 12V. If we use this one, converting it to 12V looks to be an expensive pain. Adding a 24V battery and 24V alternator seems to be the better option to improve running time and preventing it from draining the vehicle batteries.

What do you guys think? Does anyone have experience adding a 24V alternator and battery to a DT466?

[joeblack5]

To bad it is not a webasto 17 tsl... We could have traded...... I have a 12 volt unit in a 24 volt bus and use a step down converter. Works great ..would imagine that you can find a 12 to 24 converter at 15 to 20 amps on the 24 volt side. Not sure about the 90 startup current but mine draws about 15 amp during startup.

Later J

[PNW_Steve]

Originally Posted by joeblack5

To bad it is not a webasto 17 tsl... We could have traded...... I have a 12 volt unit in a 24 volt bus and use a step down converter. Works great ..would imagine that you can find a 12 to 24 converter at 15 to 20 amps on the 24 volt side. Not sure about the 90 startup current but mine draws about 15 amp during startup.

Later J

Me too... 24 volt house battery and a 12v Webasto.

[inhof009]

Originally Posted by joeblack5

To bad it is not a webasto 17 tsl... We could have traded...... I have a 12 volt unit in a 24 volt bus and use a step down converter. Works great ..would imagine that you can find a 12 to 24 converter at 15 to 20 amps on the 24 volt side. Not sure about the 90 startup current but mine draws about 15 amp during startup.

Later J

How well does that unit heat you? 17000BTUs seems a bit low for my interests of comfort in northern winters, which is why I was looking at the 30000BTU unit.

[inhof009]

Originally Posted by PNW_Steve

Me too... 24 volt house battery and a 12v Webasto.

See, that's the easier way to do it. Stepping up voltage seems like a massive pain. What size unit did you end up going with, I recall coming across your post looking for a heater.

[PNW_Steve]

Originally Posted by inhof009

See, that's the easier way to do it. Stepping up voltage seems like a massive pain. What size unit did you end up going with, I recall coming across your post looking for a heater.

Yeah, I found a 45k BTU Webasto for a bit over $400 including shipping on eBay.

[inhof009]

Originally Posted by PNW_Steve

Yeah, I found a 45k BTU Webasto for a bit over $400 including shipping on eBay.

Ah, the elusive webasto scholastic! That always comes up when searching for hydronic heaters on here, but I've never been able to find any for sale at those prices. Seeing as this unit is 24V and you run a 24V system, you wouldn't want this one instead, would you?

[inhof009]

I also found this in my searches:
https://www.ebay.com/itm/X45-Pro-Hea...oAAOSwKHtduL2t
Basically the proheat version of the scholastic. The only issue is it doesn't come with any controller, wiring, fuel lines, or case, which can get pretty pricey.

[joeblack5]

I agree, oir webasto is probably marginal enough. We have floor heat with additional heater core and fans. Below 50F we have to run the fans onthe heater core to stay comfortable. The webasto is still cycling hi / low so I think that it has some capacity left.


The bus is insulated but I have not completely finished the double pane windows. nor did I insulate the wheel well ... they are completely inside the bus because it is a low floor model.


My concern with the original coolant heater that i had in there was that the power draw and noise level was a lot higher then the webasto TSL 17 . Something that i was not happy with with the original coolant heater the bus came with.



Good luck J

[PNW_Steve]

Originally Posted by inhof009

Ah, the elusive webasto scholastic! That always comes up when searching for hydronic heaters on here, but I've never been able to find any for sale at those prices. Seeing as this unit is 24V and you run a 24V system, you wouldn't want this one instead, would you?

I think that the gent I bought mine was buying buses at auction and parting them out. He had more than one Scholastic for sale when I bought mine.

Get a shipping quote and we can see if it makes sense cost wise.

[inhof009]

Originally Posted by PNW_Steve

I think that the gent I bought mine was buying buses at auction and parting them out. He had more than one Scholastic for sale when I bought mine.

Get a shipping quote and we can see if it makes sense cost wise.

Here's the webasto 90S post on CL, take a peek and see if it's something you think is worth asking after (as I'm new to the heater world):
https://austin.craigslist.org/rvs/d/...993737019.html

[cadillackid]

I have a TSL 17 new in a box.. I thought it said those are 12 or 24 volt.. id have to read the instructions again on it..

[inhof009]

I took a gamble on a chinesium heater, so we'll see how that works out.

In the meantime, if anyone was interested in the aforementioned heater on CL, you can reach out to that guy to see if he's still selling it.