Still confused!

Oops. my bad

 

15’ class a … 5’ above peak .. in the wide open. Clean as a whistle…
Maybe I’ll put in a port for checking chimney draft

 

I do push the ashes forward.. just toss more wood in… maybe there is something similar on this one… probably due to empty the ash pan… been about a month..

 

Good idea...also, anything change around your house lately...like you sealed an air leak, beefed up insulation...or some sort of vent fan running that doesn't normally? (or even just the dryer or a central vac system running a lot?)

 

No … we did the roof, air seal, and attic insulation 2 summers ago… nothing new for this year. Plus this stove has a 4 “ outside air kit hooked up. About the time the wife and I think we have it working right, it throws us a curve ball..
I’m starting to think it just might be the wood has a bit too much moisture… or our cat is getting lazy…

 

OAK clear? No obstructions like a dead cat crawled inside?

 

Nitrodave just so you know you're not alone, here's a convo from a couple years back that was going on in another site.
The occurrence sounds somewhat common. Hoping you can figure a way to avert it happening over and over.

 

No… I even unhooked it to try…….

 

The worst part of this is, sometimes it happens 2-3 hours after a reload. Kinda makes one nervous about reloading at night… or leaving the house in the morning… or…. We’ll just about anytime .

ps… burns just fine with cat bypassed, or air wide open… just burns too hot .

 

Nitrodave, do you plan on calling Woodstock to see what they say?

 

When I get a chance….. unfortunately selling high dollar lpg trumps most everything else this time of year …

 

This is a very hard burn at my house. This data may be from the time the temp. dropped to -9, pretty rare around here. The four temps. are from the firebox, at the top of the firebox on the left side (looking at the stove, same side as the bypass lever is on); the combustor, right above the center of the combustor; the stove top at the hottest point on the stove top; the flue, inside the center of the flue (not smoke pipe wall temps. but actual flue gas temps) after the elbow and just before exiting into my chimney thimble. The X scale is in time, denoted on the bottom in 24 hour time. In this particular graph, the stove is putting out a great deal of heat for the entire day and you will notice that at the refill on the second day around 9:00 AM, the stove is pushed hard to again produce a great deal of heat. This is absolutely NOT the normal running mode of my stove but I chose this data as it pretty well shows the relationship between firebox and combustor temps. as well as stove top temp. relationship to the other three. The best indicator of the stove's actual heat output will come from the stove top temp. curve- when at 350F, the stove is producing enough heat that it can be felt in the room with the stove. By 400F, it is really cranking and at the peak temps. in this graph, around 550F, I cannot sit in front of the stove as it is uncomfortably hot.

I can expand on a single burning cycle so it may be easiter to see what is going on.

You can see the reloads (the nearly vertical spike in combustor / firebox temps., as well as when the bypass is closed (the combustor continues at high temps. or actually increases while the firebox temps. drop). Then the stove enters the gas burning phase as noted by high combustor temps. Next is the actual fuel burn, and in some places on the graph it can be seen when the firebox / stove top temps. rise w/out much or any change in combustor temp.; this is where the draft is fully opened to burn down the last of the wood and coals. The next step is a reload, where the combustor and firebox temps. fall way off as the stove door is opened, followed by a sharp increase of combustor temps. as the new fuel starts putting out a lot of gas and the combustor is burning that gas. Also the high temps. on the combustor climb to nearly 1,600 F and that too is very unusual for my stove as again, it was being pushed to produce heat on a very cold day.

The temps. are accurate to less than 2%, which means when the combustor is reading 1,500F, the reading is accurate to a max. error of + or - 15 degrees. More than accurate enough for our purposes.

Let me know if you have any questions and I will try to explain the graph and again, I would be happy to expand one stove- load buring to take up the whole graph, which will probably make it easier to see what is going on.

Edited to add: yep, it was -9 degrees when this data was collected. Very cold for this area and the hardest I have used the I.S. since install back in '14. This is not a typical burn.

 

That chimney seems a tad short, at least to me. Perhaps a 4' extension would gain a lot of benefit regarding draft? Also, do you have an all- direction venting cap on the chimney? They do a great job of keeping the wind at bay, both damping down on the increases due to wind but also the lack of draft also caused by wind from a specific direction. The buildings / tree lines and so forth around you will also make a difference as to how consistently the chimney draws, again something that may be aided by an extension to your existing chimney height.

 

It’s as good a theory as any. Could be a combination of too much moisture and a marginal stack height. My IS does occasionally backpuff if I damper it down too quickly and extinguish the flame. Though not as violently as you describe. My stack is at the lower threshold and I intend to add 3-4 feet in the spring when the roof is safe.

 

Nitrodave , are you running a screened chimney cap, that may be getting crusted over?

 

Thanks for the info… I’ll have to look at it another time… my head hurts too much to comprehend it tonight.

 

I may have to try more chimney… just have to keep it lower than the trees… otherwise it may get hit by a chopper or A-10….

 

Nope… ripped the screen out after the first winter….

 

Just a normal Simpson cap minus screen….