Diesel heater questions.

scootermcscoot · 01-07-2018, 11:27 AM

So we just figured out that our Eldorado shuttle bus has at least one diesel heater. Only thing is we've never come across these before so we're a little stuck.
We've downloaded the manuals for one of the heaters (an Airtronic D2) and have figured out how to turn it on but it is it blows cold air, not ideal when it's already -20C outside. It could be lack of glow in the glow plug or lack of diesel but I don't know if either of these are checked as part of the initial check that runs when you turn the heater on.

Does anyone have any experience with troubleshooting such things?

Secondly, right next to the heater is what looks like a big cube shaped radiator that I thought was essentially a heat exchanger for the engine coolant pipes and the source of heat for what I originally thought was just a fan next to it that turned out to be the D2. Now I know about the D2 I have no idea what this box is.

And finally, at the back if the bus mounted where the floor meets the back wall is another heater if some kind. I haven't been able to identify it yet but it looks like it might have intake and exhaust fittings on the bottom that pass through the floor.

To add to the confusion our dash has 2 three stage rocker switches (low\off\high) labelled HEAT and 2 mini switches for the Eberspacher labelled Front and Rear. The front one definitely turns on the D2 but the rear one doesn't seem to do anything.

I've attached some images which I'm hoping will help make things clearer. Thanks in advance for any information or advice anyone can provide. We haven't made a ton of progress but without you guys we wouldn't have made any. Thanks and Happy New Year

Defjr333 · 01-07-2018, 11:33 AM

From your description the Eberspacher should be plumbed to both the cube beside it AND the box at the rear. The 2 switches are for the fan speed associated with each unit. At least thats how I would have installed it. But that does not allow use of engine coolant to heat with. Seems the rear heat HAS to burn fuel to work? Or the factory units stopped working and it was just easier to install the Eberspacher than troubleshoot/ fix the original? Hard to say without being able to trace any lines.
Doug

BlackJohn · 01-07-2018, 12:13 PM

Ok, one step at a time with your problem heaters.

The D2...up to you to prove if it has fuel. Might be a shut off valve going to it. Trace lines back to fuel source. Should be before a fuel filter for the unit itself.
Valve if any might be open but filter clogged or frozen up with water in that part of the fuel system.
You have some power due to fan running blowing cold. There will be a nozzle on the burner that might need changing/cleaning for fuel to get to the igniter/glow plugs or whatever that uses.
Your bus has a Durmax? Do you use it regularly? Starts ok etc? Maybe some fuel additive because at -20canadian you will have gelled fuel if it sits very long. Run that engine to get some heat built up in the fuel lines to maybe help thaw it out. Get fuel from Irving truck stops who sell loads of it, not a gas bar fuel.
Only -41 here canadian but rising to -6 tonight. Niagra Falls is frozen over and not falling due to the cold. What will people do on their honeymoons there? lol

Keep trying and keep us updated on how this goes for you.

John

scootermcscoot · 01-07-2018, 04:43 PM

Hi John. The bus gets started at least twice a week and runs for about 45 minutes as I drive from Sackville to Moncton and then back a few days later. As well the occasional short trip around town. Never seems to struggle to start. Supposed too be warming up next week so I'll get chance to get under it and have a look at what's going on there, will post findings and any pics then.

BlackJohn · 01-07-2018, 05:02 PM

Quote:

Originally Posted by scootermcscoot

Hi John. The bus gets started at least twice a week and runs for about 45 minutes as I drive from Sackville to Moncton and then back a few days later. As well the occasional short trip around town. Never seems to struggle to start. Supposed too be warming up next week so I'll get chance to get under it and have a look at what's going on there, will post findings and any pics then.

Seems the bus works well. I know that country well being from Springhill, N.S. Where winter is winter!

Yes, read as much as you can on the heater operation so you know exactly what to expect. Could be a fuse issue on the other at the back. I think that would be run off the engine cooling system for extra rear heat.

John

rffffffff · 01-08-2018, 10:58 AM

Had two heat exchangers that were plumbed to the engine and switched just like your front and back heaters. There is a valve to turn off the coolant flow to them in the engine compartment for the summer and the switches just turn on the fans that blow air through the radiator to heat up the space when the engine is hot.

The espar that you have looks like an air only unit that would be used heat the space without the engine running. Based on what I know it can not easily be integrated into the other heaters so I believe they are completely seperate systems.

I bought a knockoff diesel heater just like the espar and it's very weird in operation... they take quite a while to turn on and get warm, it purges first, does its thing, turns on and off then starts actually trying to make heat. The fuel pump clicks when it's trying to work, so assuming yours is the same, I would pull the fuel line off of it, turn it on, wait a bit until you hear clicking and see if fuel comes out of the line before you do much else. Once you sort out of you have fuel to it you can really begin to troubleshoot!

scootermcscoot · 01-10-2018, 04:26 PM

Thanks for all your responses folks. Gonna check on the file supply this weekend if it stays warm enough.

Jolly Roger bus 223 · 01-10-2018, 04:42 PM

If you are already messing with the fuel lines.
I like to add inline clear-view filters on either side of the main filter to see incoming and outgoing fuel.
Mr. Gasket clear vue is about the cheapest one.
Good luck

cadillackid · 01-10-2018, 04:58 PM

make sure your fuel is full... its pretty common to plumb those heaters in so the fuel pickups for the heaters is at a higher place in the tank.. (1/4 tank or more).. so that if you accidentilly left the heaters on they wouldnt run you out of diesel fuel..
-Christopher

JDOnTheGo · 01-10-2018, 05:09 PM

Quote:

Originally Posted by rffffffff

The espar that you have looks like an air only unit that would be used heat the space without the engine running. Based on what I know it can not easily be integrated into the other heaters so I believe they are completely seperate systems.

I agree with this.

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