Smoke & Dripping from Alde Outlet 2015 320 s Boondock - Resolved by removing bee nest

michaelroyy

Turned the heat on full throttle. Maybe 5-10 minutes, I came back to see smoke coming out of the Alde outlet along with some moisture dripping (attached a picture of each). It didn't smell like a fire and no smell inside. The heat was on inside. The outlet is blackened, but not really hot or melting. Shut it down to see if I can get some advice. 

Grumpy_G

Generally speaking every time you burn hydrocarbons it creates water, typically in the form of water vapor (in the winter the water condenses back into liquid and drips out of the exhaust of a car e.g.). So it is not uncommon to see some vapor and some water coming out of the Alde exhaust in cold weather. It shouldn't happen in current spring temperatures though, and it should not be black either. Combustion in the Alde might be incomplete generating a lot of soot, or it is burning something else like heat transfer fluid. How does the level in the Alde reservoir look ? If it's not burning transfer fluid just let it run longer and see if it clears up. You don't need to turn on the heat for that just hot water. The boiler heats up to an internally set temperature either way. 

michaelroyy

Thank you for this and all the great feedback you have provided me and to others on this forum. Very much appreciated. I will run it tomorrow on just the hot water to see what happens.

pthomas745

This has happened before, and Grump-G's explanation explains most of it.   Condensation is the most common cause here.  The next question is what altitude are you?  The Alde 3010 trailers (the Beta version of the Alde) had a basic design issue: it would not properly burn propane at "high altitudes"....which Alde decided was "above 3000 feet".  I shake my head at a lot of Alde design issues, but that one takes the cake.

So, part of what you are seeing with the "sooty" exhaust is that combustion issue.  This has been reported before, and I'll see if I can find other posts about that issue specifically, but all of this goes back to the "combustion at altitude."

The "newer" Aldes, the 3020, has the combustion fix built in, but owners still have to select the "high altitude" mode.  There was a huge thread about this issue back in the first year of the Alde when owners reported a "rumble" in the Alde while running on propane at altitude.  The sound was variously described as a "freight train" noise, hence the name of the thread: The Alde Freight Train.  Not all of the Alde 3010 models ever had the noise.  My 2017 never makes a peep, all the way up to 9000 feet, so..who knows?

This is the link to the thread that you might want to review, there are other threads about this.  The basic "fixes" have sort of been forgotten since the Alde 3020 came around, and I'm not sure if the basic Alde parts are still available in the US.  So, check this out and get the proper explanation of the "combustion", since I don't think I've explained it well.

https://tab-rv.vanillacommunity.com/discussion/3030/alde-freight-train-alde-3010-model/p1

Edit: of course, it took one correct search to find the threads about the Sooty Exhaust!  Check these threads first, since they should get right to the heart of the matter.

https://www.qwant.com/?client=plgn-firefox-sb&q=sooty+alde+exhaust+site:tab-rv.vanillacommunity.com&t=web

Grumpy_G

Interesting, the "freight train" discussion predates me joining the forum. My trailer is a 2015 with the Alde 3010 just like the OP's and I live at 3300ft so most of my camping is at higher elevation. I never had the soot problem but the Alde tends to rumble a bit. The fridge actually has a more noticeable noise at high elevations. 

michaelroyy

Thank you for the research and comments. I followed Grumpy's suggestion of just turning on the boiler for hot water. See attached photo of the setting. When I did this, there was hot water, but the steam/smoke came out the outlet. I let it go for 5+ minutes before I shut it down. The glycol level (photo attached) was just above the minimum. I have no idea if it has dropped significantly because of this issue, but I can monitor it.

As far as Thomas' advice and threads, I am in the Seattle area, so no elevation to address. I read through the threads, but they mostly had to elevation. It is possible I missed a tidbit... 

Would appreciate any thoughts on what to try or think about. Appreciate you all. 

pthomas745

I just looked over the weather reports across the SEA area (airports, mostly) and the first thing I noticed is the quite high dew points and relative humidities.  We mentioned condensation...and I'm willing to be the "smoke/steam" you are seeing is condensation at the exhaust.

Whether or not the "steam" is also carrying enough poorly combusted propane to cause the sooty deposits is hard to say. In some of the "Alde High Altitude Mode" discussions, it seems Alde simply increase the exhaust fan speed to provide a "cleaner burn" of the propane, which helps prevent the "freight train" noise. 

So, there could be several things happening: fan slowing down after 10 years?  Too much humidity?  Might something be inside the exhaust hose slowing the exhaust a bit?

Grumpy_G

Soot would indicate either more fuel or less air than what the boiler was designed for. Could be the gas pressure is too high (unlikely) or the air intake is clogged. Remove the cover on the outside, there are two concentric tubes behind it. The inner is the exhaust and the outer is fresh air for the burner. See if any insect has set up shop there. Worst case remove the whole tubing on the inside of the trailer. 
The gas side is more tricky, the proper way would be to measure the gas pressure which is rather low at 11-13 inches of water column (WC) or less than 0.5 psi. There are simple DIY manometers that directly show inches of water column and are much more accurate than a dial gauge. Come to think of it, give the propane regulator a couple of taps, it's a mechanical device after all. 
The exhaust fan speed is monitored by the Alde controller as a safety feature and it does shut off the burner if the fan is not spinning, but I don't know if it detects a slow spinning fan. 

michaelroyy

I am going to take off the outlet tomorrow to see if there is anything obstructing the flow. If I don't get lucky fiddling, I will call Alde on Monday to hear what they have to say.

michaelroyy

I figured out my problem. I bee nest… Cleaned it out and it works great!!!