Aquahot sooting up

[gumpy]

I just spent a week and a half in the bus in cold country. I had a bit of a problem with my Aquahot producing copious amounts of soot. It built up
literally 1/4" of soot around the inside of the entire exhaust pipe! I've never had this happen before, even at 10000 foot elevations. We were in
Denver and Pueblo, so not really that high.

I think soot is normally caused by not enough air for the amount of fuel. The air intake setting hasn't been changed on the Webasto head, so I'm
thinking it's probably time to change the fuel nozzle. I haven't done that in several years, but then again, I haven't really used the coach much when
running the aquahot burner was needed for many years.

Any other ideas?

[luvrbus]

I would change the nozzle 1st then check the voltage and rpm on the motor they soot like a coal burning train when the motor starts to get weak and looses rpm 

[Oonrahnjay]

I would change the nozzle 1st then check the voltage and rpm on the motor they soot like a coal burning train when the motor starts to get weak and looses rpm    

     What does the motor do, Clifford?  Is that a fuel pump/supply motor?  Thanks (I'm trying to learn about the things that they don't tell you in the books.)

[David Anderson]

I had this same miserable problem at Breckenridge ski area one year.  We nearly froze trying to live off 4 electric heaters in 8 degrees.   After several calls to Dick Wright and Sure Marine I tried several things.  First I shortened my exhaust pipe from about 14' to about 3.5' in length.  I cleaned out all the soot in the chamber and washed out the exhaust pipe.  It was caked.  I installed a new nozzle and fuel filter.  Sure Marine suggested to open the air baffle at the intake of the burner just a bit in high altitude.  Index the baffle before you change it so you can return it to the factory setting.  I agree that Denver and Pueblo shouldn't warrant a change of the air intake.

Apparently all this has served me well.  I've used it in Cloudcroft (8K feet) and it hasn't failed since.  I believe that it should be cleaned annually of any soot.  I'm two years into a new nozzle, so not sure how long you can go without replacement.  I think this will be the 3rd winter (2016) with the nozzle and I haven't been out to cold country yet.  We're going out in January, so I'll probably know then.

These heaters are the best when they work, but I agree that they need lots of preventative maintenance to work in top shape.

David

[opus]

Nozzle should be changed yearly.  Be careful, you arent getting a good spray.  I burnt a Webasto up from that, many moons ago.  I also learned that they dont run nearly as good with 12v as they do with 13v.  Therefore, I havent run mine off battery power since.

[Gary Hatt - Publisher BCM]

If you have an Aqua-Hot, Webasto or Hydro-Hot system and will be at the Quartzite rally, there will be a top notch mobile service technician there. He recommends annual service on your system.  I have him service my Aqua-Hot system every year in Quartzite.  Either stop by our booth in Quartzite or call Lloyd DeGerald Services directly when you get there at on his cell at 501-258-8426.  He will be staying close to us at the rally and will be able to service any unit you have and is very fair.  For information about other rallies he will be attending this year check out his schedule at www.lloyddegerald.com/locate-me-calendar. 

[rusty]

Craig, The next time you are in Colorado and on your way to Wyoming there is a young man named John Carrillo that lives in Longmont that works on hydronic heating systems of all kinds and is very good at what he does. He once changed the nossel twice to get my burner to burn the fuel completely. In the winter he is down south working the get togethers down there. He spends most of the spring summer and fall at home. His number is 970-518-3085. If you need palace to hold up for day or two so he can work on your system you are welcome to stay at the house. John has been to our place a few times to work on other peoples systems.

Wayne

[gumpy]

Thanks, all, and especially Wayne for the offer.

Most of this is confirming my thoughts. I'm going to change out the nozzle this spring when it warms up again. I'll clean out all the soot in the pipe and see
what happens then.

The comment regarding the voltage is interesting, because my house batteries were exhibiting signs of weakness when we were camped
at Cabela's in Denver (they're only 11 years old!).

The Aquahot had pulled the voltage down to under 24 volts in just a few hours and I had to run the generator. Other than that short period,
either the generator was running or the bus was plugged into shore, and the inverter was charging with proper voltage.

I've run this unit for about 12 years with no problems ever, and that include elevations up to 10000 feet, except for a leaking o-ring on the fuel pump.

I'll start with the nozzle. If that doesn't help, I'll seek help from one of the numbers listed in the comments.

thanks again.
craig

[dickegler]

Don't forget to pull the burner can out and clean it and the housing as well!

Dick

[gumpy]

Don't forget to pull the burner can out and clean it and the housing as well!

Dick

Yes, I will do that.

I have to find a cable or something I can improvise a sort of rotor-rooter with to clean out the pipe. That soot really sticks to the walls. I thought the trip home
on all the rough roads would loosen some of it, but didn't seem to lose much that I can tell.

[luvrbus]

     What does the motor do, Clifford?  Is that a fuel pump/supply motor?  Thanks (I'm trying to learn about the things that they don't tell you in the books.)

Bruce, the motor drives the combustion fan and a gear reduction on a shaft for the fuel pump drive they turn around 5000 rpm best I recall and when voltage is low or the motor starts to weaken they soot up pretty fast.fwiw that is 1 pricey little motor low voltage will destroy BTDT   

[Oonrahnjay]

Bruce, the motor drives the combustion fan and a gear reduction on a shaft for the fuel pump drive they turn around 5000 rpm best I recall and when voltage is low or the motor starts to weaken they soot up pretty fast.fwiw that is 1 pricey little motor low voltage will destroy BTDT   

    Thanks, Clifford.  That sounds like a lot of load -- no wonder they don't like low voltage.  Is there also a circulation pump in a Webasto and Aqua-Hot to circulate the heated anti-freeze mixture (I'm assuming that people use anti-freeze in those circuits)?  People talk about how much juice they pull when they're running -- i'm beginning to see why!
    I appreciate the info.  It's helpful.

[opus]

    Thanks, Clifford.  That sounds like a lot of load -- no wonder they don't like low voltage.  Is there also a circulation pump in a Webasto and Aqua-Hot to circulate the heated anti-freeze mixture (I'm assuming that people use anti-freeze in those circuits)?  People talk about how much juice they pull when they're running -- i'm beginning to see why!
    I appreciate the info.  It's helpful.

Yes, there is a circulation pump on the tray of the Webasto.

Like Clifford said, if the voltage gets too low, your spray turns into droplets, which turn into a fireball, which can splash back and melt all the innards.  Dont ask.....

[buswarrior]

And if it burns wrong, the safety sensors in the top will have to be replaced. More $$$ better spent on annual preventive maintenance.

I keep a little plastic box with a set of those and a nozzle, next year's replacements available for early deployment.

happy coaching!
buswarrior

[Gary Hatt - Publisher BCM]

I sent Lloyd DeGerald (my Aqua-Hot service guy) the thread and this is what he said.

Answer:  Black smoke or soot is caused by incomplete combustion .  Aqua Hot recommends exercising the diesel side of your unit monthly, every month.
Unit should be serviced yearly.
Not exercising your unit monthly can cause nozzle to fail. 
Soot can also be caused by a grommet not seating correctly.
Soot can also be caused by motor not running @ 4500-5000 ROM's.
Improper air adjustment can cause black smoke-screw should be set in the middle.
White/Grey smoke is result of unburned fuel. 
Recommendation;  Start with annual service as first step.

He said you can feel free to call him if you have further questions.  He can be reached at (501) 258-8426 and he does take calls on weekends.  Click on his Banner Ad for his information and traveling schedule.