Wow, what a trip

Torquester · December 25, 2006, 04:49:00 PM

David,

I'm talking about fuel pressure from the pump in the burner. iirc somewhere north of 100 psi. I'm pretty sure that some of the school districts up there are running these units in their busses (Aspen, Vail, etc.) Something ain't right. Even if your 12 volt system shows 13.whatever....you gotta' measure voltage AT THE BURNER UNDER LOAD. This measurement will rule out high resistance connections or other issues.

Please keep us posted. As you are well aware, we will try to help.

Tq

David Anderson · December 26, 2006, 06:51:33 PM

Thanks Tq. I'll mention that to Mr. Edwards.

Nick,
The webasto tech named Gilbert, that I spoke with on Dec 19, said there is no way to change fan speed on this model. Unfortunately, that is not an option on the DB 2010. He suggested I buy a bigger unit. Yea, right.

David

Nick Badame Refrig/ACC · December 26, 2006, 07:34:23 PM

OK David,

Your option is to reduce the nozzle size and sacrafice some btu's in the high eleavations.

It's a shame the didn't build an air adjustment into this unit. I guess they think everybody lives at sea level.

Is your nozzle accessable without tearing the whole unit out?

If you can tell me the nozzle size and degree I can put you in the ballpark on a smaller size.

Nick-

DrivingMissLazy · December 26, 2006, 07:57:22 PM

Quote from: Nick Badame Refrig. Co. on December 26, 2006, 07:34:23 PM
OK David,

Your option is to reduce the nozzle size and sacrifice some Batu's in the high elevations.

It's a shame the didn't build an air adjustment into this unit. I guess they think everybody lives at sea level.

Is your nozzle accessible without tearing the whole unit out?

If you can tell me the nozzle size and degree I can put you in the ballpark on a smaller size.

Nick-

I really doubt if he will lose any BTU from what he has been getting since it is burning so poorly. In fact I suspect he will gain BTU overall if he gets it burning correctly. At least that is the way it was with my waste oil burner. They also emphasized the importance of having a good open exhaust stack.
Richard

Brian Diehl · December 27, 2006, 06:33:24 AM

Quote from: David Anderson on December 26, 2006, 06:51:33 PM
Thanks Tq. I'll mention that to Mr. Edwards.

Nick,
The webasto tech named Gilbert, that I spoke with on Dec 19, said there is no way to change fan speed on this model. Unfortunately, that is not an option on the DB 2010. He suggested I buy a bigger unit. Yea, right.

David

David,
If you have the standard DBW2010 like mine there should be a shutter on the underneath side of the head. On my unit the shutter is adjustable. Last summer when I was up in the Big Horn mountains at 8000' I just opened the shutter up more until the exhaust cleared up (smoke went away). Doing that worked great for me.

Also, on the nozzle, do you have the "newer" style 0.35 nozzle or the "older" 0.40 nozzle? When I just replaced my nozzle I had the older style in it and all I could get was the new style locally here in town.

-Brian

David Anderson · December 27, 2006, 06:03:51 PM

As per Mr. Edwards instructions I opened the air damper all the way at Breckenridge and tinkered with various other settings, too. It didn't help. I could really hear the flame noise go down when the damper was adjusted toward the closed position. The damper setting makes a big difference in flame size.

I have a .35, 60 degree nozzle. As I stated in the original thread I replaced the nozzle at Breckenridge with a new one just to check if it would get better. It never quit smoking and ran about an hour before it choked itself to a flame out. I waited a day and cleaned all the carbon black out of the burner tube and chamber so I could use it on Friday to get enough heat to start the engine. That worked well enough to get us going, but it again choked itself up with so much soot that it wouldn't work when we got to Dumas.

After Dumas I cleaned it out again, adjusted the damper back to the factory setting and ran it for 3 days at the inlaws in Pampa and it never smoked a bit. Pampa is 3300 feet msl. I even put the up stack pipe on it to carry the fumes above the bus. That made the exhaust run 22' with an extra 90* turn and it didn't effect it a bit.

I havent' contacted Mr. Edwards yet for help. I've been too busy catching up at the office.

Brian, where is a good place to get nozzles? I've been buying from Wrico, but the shipping from the left coast to Texas is about $15. There ought to be a less expensive alternative.

David

David Anderson · December 27, 2006, 06:29:07 PM

I just pulled out my invoice from Sure Marine from back in July 2004 when I sent the heater in the first time it happened. All they did was change the nozzle, but typed a note that said, "smoking may have been caused by unburned fuel in the exhaust pipe." That is something I've never looked at. Perhaps I need to do a "chimney sweep". What would be good to tie onto the end of a hand cranked sewer snake cable to scour the pipe out? It's worth a try, because that is one thing in the puzzle I haven't attempted.

If Brian's heater will work at 8000', there is no reason mine shouldn't either. There has to be a solution.

David

Nick Badame Refrig/ACC · December 27, 2006, 07:59:24 PM

David,

Something I just thought of.. If the unit has a selonoid valve to cut off the fuel feed, it's possible that the valve

may be leaking fuel into the chamber when the unit is off and causing raw fuel to enter the chamber. Then when you fire up the unit

you will have a rich condition causing what firemen call backdraft or a build up of unburned fuel which will then soot.

Just a thought!

Nick-

DrivingMissLazy · December 27, 2006, 08:55:36 PM

Based on what you have done and said, I am going to guess you havve a draft problem. Too small a stack pipe, too many bends too long stack or something like that. Mine always smoked when I first lit it off, but it always cleaned up after running a few minutes. An extra 22' of pipe should really create problems. Do not know why it did not.
Richard

David Anderson · December 28, 2006, 09:35:55 AM

It wasn't an extra 22', just an extra 11'. My stock length is 11' with 139 degrees of bends.

David

DrivingMissLazy · December 28, 2006, 10:08:37 AM

David, I strongly susspect you have about eight or nine feet too much of stack. Also, my oil heater indicated a maximum of 90 degrees of bend.
Richard

Quote from: David Anderson on December 28, 2006, 09:35:55 AM
It wasn't an extra 22', just an extra 11'. My stock length is 11' with 139 degrees of bends.

David

David Anderson · December 29, 2006, 01:08:46 PM

Brian,

What size is your exhaust pipe and how long and how many bends? Mine is 1 1/2" x 11' with 130* bends. I'm thinking about upsizing to 2" x 5' with one 90* bend, inconvenient for the bay doors, but should eliminate any airflow issues.

David

Brian Diehl · December 29, 2006, 07:08:31 PM

Quote from: David Anderson on December 29, 2006, 01:08:46 PM
Brian,

What size is your exhaust pipe and how long and how many bends? Mine is 1 1/2" x 11' with 130* bends. I'm thinking about upsizing to 2" x 5' with one 90* bend, inconvenient for the bay doors, but should eliminate any airflow issues.

David

Hi David,
My unit is setup with one 90 degree angle (long sweep) and about 16" of exhaust pipe.
-Brian

David Anderson · December 30, 2006, 12:38:56 PM

Wow Brian,

That is a very short run and good planning on your part. That has to be a factor in my problem. I can shorten mine to 4' with one 90* sweep bend. Hopefully that will solve my problem.
Also, I'll continue to tinker with the shutter above 8000' to get the cleanest exhaust possible. We won't be going back to the mountains anytime soon, so the test will be a long time in the future.

David

muddog16 · December 30, 2006, 02:50:07 PM

This was a very interesting thread one of the best I've read in a long time! From excessive fuel on start up, to length of exhaust and number of bends and fuel temp....what it sounds like is a screw up from the manufacture.......they need a variable speed fan motor that runs according to the barometric pressure, this fan would increase speed with the variable being the barometric sensors signal......That is a problem for the factory not rejetting or jury rigging a fix, this could be a serious problem, I'd make them fix it.............if they advertised it to run at that altitude then it should without any problems! AS LONG AS YOU INSTALL IT PER THEIR SPECS! 6,000 bucks is a lot to spend for something that won't run as advertised!

Pat

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