Webasto smoke on startup

[BUR]

    Just installed Webasto, it runs fine but smokes on start up.  When it first fires up I get more  smoke than I like (or my neighboring campers might like). It doesn't sound like a good burn when it fires up, but then it cleans up and sounds better and quits smoking. Is this the norm? Would air intake adjustment help.
                                                         BUR

[gumpy]

    Just installed Webasto, it runs fine but smokes on start up.  When it first fires up I get more  smoke than I like (or my neighboring campers might like). It doesn't sound like a good burn when it fires up, but then it cleans up and sounds better and quits smoking. Is this the norm? Would air intake adjustment help.
                                                         BUR

This is not unusual, and varies with temperature. The colder it is, the more it smokes and the longer it smokes.

It's possible it may need a tuneup. Maybe an air adjustment and a new nozzle. Nick can probably give more info on this than I can.

Consider building a stack you can hang on the side of the bus when parked to run the exhause to the roofline. Makes for happier neighbors.

[BUR]

       Thanks Craig forgot to mention its a new unit.
                                                                    BUR

[Frank @ TX]

Hi Bur,
I have an AquaHot since 2001.  
At the heart of the unit is a Webasto burner head.
Last year mine started puffing smoke at start up.
I replaced the burner nozzle and adjusted the air control more open.
My air control is now set exactly in the center now.
I don't know where it was before or if it vibrated off that setting.
Also , gumpy has a VERY good idea, plumb the exh up to the roof.
I have my (2") exh pipe in a 6" dia outer pipe.
The exh is just inserted the whole way to the roof while it's in the 6" the outer pipe.
That way the exh is at the roof and the outer pipe keeps nice and cool.
Design what is best for you.
Frank

[Nick Badame Refrig/ACC]

Hi Bur,

In a perfect world, no we don't want our Webasto's to smoke at all..

Like Craig said, they tend to smoke more at start up when it's cold outside.. Why?

Because the fuel will not ignite as quickly when it's cold.. This causes the fuel to

accumulate around the blast tube until the chamber gets hot enough to burn off

the extra fuel. Then WaLa.. smoke free...

Hope this helps
Nick-

[BUR]

     Thanks Craig, Frank, Nick, You guys confirmed that I that I probably don't have a problem. I pulled the bus out of the garage to test the Wabasto. It was around 25 deg. out that day. I will build an exhaust stack that I can double duty use on genset in the summer.
                                                                                                Thanks again  BUR

[Don Fairchild]

Mine has a pre-heat that I use and it still smokes on start up when it works. I have yet to drop it out to clean it up and check it out, and install the new new nozzle I bought from Nick.

Don

[luvrbus]

A question for you guys building the stacks reading the manual on a pro heat it is very limited to the length of a exhaust pipe and bends 500 or 600 degrees is a lot of heat and what about back presssure on the head ? I don't  know if that is a good idea on a diesel fired system all the exhaust pipes I have seen on diesel fired systems are 4 or 5 ft long at the most


good luck

[Don Fairchild]

Clifford you down in Houston, Hows the weather down there. I may be in San Antonio around the middle of Jan.

Maybe we can meet some where in the middle and share a meal.

Don

[Nick Badame Refrig/ACC]

A question for you guys building the stacks reading the manual on a pro heat it is very limited to the length of a exhaust pipe and bends 500 or 600 degrees is a lot of heat and what about back presssure on the head ? I don't  know if that is a good idea on a diesel fired system all the exhaust pipes I have seen on diesel fired systems are 4 or 5 ft long at the most


good luck

Hi Clifford,

The way to eliminate that problem is to step up in pipe size before every elbow in your pipe run.

Hope this helps
Nick-

[Bill B /bus]

Depending on outside temperature. At 20 degrees on a cold start the unit will produce heavy white smoke, noise will sound as if flame stuttering. As Noise smooths to a steady note the smoke will become less noticeable. Maybe 90 seconds to a clean output and steady noise without any flutter.
The Webasto ignitor only fires to ignite the fuel. Spark is on for maybe 20 seconds, If fire  eye senses flame then ignitor is locked out. If no flame then ignitor off for about the same time. Then ignitor sparks again for the 20 seconds. Will cycle 3 times before shutdown.
Now knowing how that works you can understand why the smoke on cold start. The flame is in a very chilly enviorment with a lot of cold air trying to blow the flame out. Hence a lot of unburned fuel on that initial cold start. Once the boiler has come to temperature you may see a short puff of white smoke at the start of the flame in cold temperatures.

Temperature here in Maine is about 20 degrees and I have been having restart issues. Culprit is a bad motor. apparently the motor has a bad spot on the commutator. Every so often it stops on the bad spot. A quick turn of the shaft and problem solved. New fan motor ordered, ouch $$, which will fix the problem.  When the unit is cold and I get it restarted the smoke is heavy and the flame stutters. That's how I became conversant on the subject while kneeling alongside the unit in the snow at 20 degrees.

Bill

[BUR]

      Bill what a great explanation of the works of the Wabasto. Thanks a million for taking the time to explain.   BUR