Blaze King 40 Smoke Smell Near Stove (No Visible Smoke) on Low Burn

So what gasket was replaced in November, the door, or the cat (both?)
Not sure if the cat gasket could even cause a smoke smell issue though, especially random/intermittent like this.
Is this the stove that is 8" on a 6" chimney? (or vice versa?) Doesn't seem like that would suddenly cause this issue after 2 flawless seasons though...

 

I tried reading through all the comments before commenting, so if I'm repeating someone else: my apologies.

Sounds like the only thing different is time. Your catalyst is 2 years older.
Early in the thread Dennis said to keep a visible flame- and that's the advice I'd give. If you're black boxing it and getting a whiff of smoke- try for a month or so with keeping a flame and see if it makes any difference.
A slight whiff when you're sitting back watching some shows is like a fart in church. Everyone notices.
Keeping the flame will probably maintain things active enough to prevent the exhaust from stalling out, especially to overcome atmospheric conditions.

 

Using a high tech mechanism (paper towel cardboard tube) today I went over the stove in various places while it was burning. I really believe I could smell a hint of smoke over the door and also at the base of the chimney where it connects to the stove. I am going to replace the door gasket at the very least. You make an excellent point, replace the cat and see what happens. I think I will get the cat but try the door gasket first before installing the cat.

I was actually the one who took the cat out and cleaned it. I only used a vacuum, making sure not to actually touch the cat. This was the method in the manual. I did this front and back. I did not perform any kind of wash on it as it was not mentioned in the manual either. The cat looked surprisingly clean, and very little ash came off it. I simply replaced a new gasket around the cat and inserted it back in the stove. Just to clarify though, the smoke smell was before removing the cat. The smell was actually my reason for doing so as I thought it might be dirty.

 

I only replaced the cat gasket, not the door. I will be doing the door gasket soon, hopefully tomorrow.

The stove is 8" on a 6" chimney. My draft is very good, and I've never had issues starting a fire and inducing a draft. The stove heats our 2500 sq ft house flawlessly which is the only reason I don't think the chimney is the problem. That being said, I floated the idea to my wife yesterday that I was thinking seriously of installing the 8" chimney, just because. If the stove was struggling to burn, or not heating like it should, I'd have installed the 8" chimney two years ago, but, it has worked so good, I saw no need to do so.

 

Ah, I thought you had done the door gasket...that's the one (I think) that BKVP said to make sure was a genuine BK gasket

 

I will say, the previous two years, I had ALWAYS burned the stove HOT, trying to keep the glass clean. It really ticked me off that I bought a stove with a nice viewing glass, yet, if I dialed the stove down, it quickly turned black and looked like crap. Last year, I actually bought a second door so I could swap a clean one, especially if we had company over, for the dirty one. I know I was probably not being the most efficient, but, oh well. So, this year, it told my wife I'm not messing with worrying about the glass and thought I'd try to be Mr. Tree Hugger and run it more efficiently. I think you all are solving my problem for me. Last two years, burn hot (hotter) no smell. This year, be Al Gore's buddy and dial it back, whala, smoke smell! I'm definitely going to dial it up a mark or two, effective immediately, and I bet money my problem will go away.

 

You are correct, I just looked at the manual and it states:

LOADING DOOR GASKET REPLACEMENT
If door gasket replacement is required, only replace with OEM door gasket ordered through your Blaze King
dealer. This gasket will be properly sized and ready to install.

 

Bring everyone up to speed.....
Today I brushed the chimney good, and then removed the pipe between the stove and chimney. Removed the cat and steel bypass door then replaced the rope gasket for the bypass door. The old gasket actually looked really good, however, it was very compressed, almost hard. Since I had to remove the cat to do this, I also installed a new gasket around cat. I asked the dealer if the cat gaskets were OEM from Blaze King, and he assured me they 100% were. He was honest with me and told me the 5/8" rope gasket for the bypass was not OEM. I'm hoping this is ok. Started a fire after completing all this. After about an hour, cat glowing bright orange, not sensing a smell of any smoke yet, but I'm still getting some smoke coming out of the chimney. This still baffles me as it's just a small fire with 3 small pieces of wood which has created a nice little fire. Cat temp gauge is really high, almost one full revolution.

We'll give it a couple days and see if the smoke smell appears at all. Fingers crossed !

 

Ah, good catch, I guess I forgot about that. With the necked down exhaust I would especially be avoiding the rip roaring warm up fire followed by a throttle chop.

When I asked about putting a king on my 6" flue, BK warned me the result would be smoke smell in the home.

When the cat wears out they smoke. Since this BK is so new it probably has a steel cat and in my experience they don't last long. There is no physical evidence of cat failure, they just stop working. I don't know what else would cause high smoke levels if your wood is good and you are running at normal output levels.

 

I hate to say it, but I think the flue size mismatch is the real culprit here. A stove that is designed for an 8 inch flue going into a 6 inch liner is not a small difference.

An 8 inch flue has about 50 square inches of area, while a 6 inch flue is only about 28. That is almost a 45 percent reduction in flow capacity. That restriction does not always show up during normal burns, but once you turn the stove down and draft weakens, it really compounds the problem.

At that point it becomes much easier for exhaust, including carbon monoxide, to end up in the house. It looks like a system limitation, and a few conditions finally lined up to expose it. The gasket notwithstanding, we all will always have some kind of a hole gasses "could" leak in through via the air intake.

In the short term I would be very cautious about running the stove low, especially overnight. Carbon monoxide is not something I would gamble with. In the long term the real fix is moving to an 8 inch insulated liner, or otherwise matching the stove to a properly sized flue.

 

Yes, you are correct. Stove has an 8" flue connection and actual pipe is 6". I think I may have found the problem. I did a couple things, I replaced the bypass opening gasket as well as a new gasket around the cat. I also sealed around the connection between the double walled pipe and the 8" to 6" reducer. At this connection, I thought I could get a hit of smoke when sniffing around it with a cardboard tube. Burned the stove yesterday afternoon and last night, and so far, absolutely no smoke smell. I'm thinking, when I disconnected the pipe from the stove when cleaning it last fall, something may not have aligned perfectly as it was before. Freak thing, but, so far so good.

I thought I had mentioned the 6 inch pipe earlier, but after going back, I never did. That being said though, while it is easy for some to immediately blame the 6" pipe, if it was a mismatch, how did it work flawlessly for two winters burning full time?

 

I moisture tested 10 random sized pieces of wood, freshly split in half. My highest reading was 12%, my lowest was 8%, but my average on most of the pieces was 10%.

For me, I would say running the stove on a low setting is an extremely rare occurrence. In fact, I never did until this year. My reasoning: it looked like it created a lot of creosote inside the stove, even though the chimney looked amazingly clean.

The way I typically burn, and the way I burned last night is with the stat set halfway between 3 o'clock and 6 o'clock. Last night, I filled the firebox 1/2 full because temps today were going to be mid to upper 30's. When I got up this morning, outside temp was 22°, indoor temp, 77°. The wood had burned down to a small pile of coals. I did not add any wood for the day because the high outdoor temperature for the day was calling for 38°, which was spot on. Right now, at 5pm, outdoor temperature is 31°, and indoor temp is 77°. I just don't do the low and slow gig. If temps are calling for upper 30's, I just let the fire die out. By evening, I can rake enough coals out of the ashes to rekindle the fire. I have no draft issue, because on restarts, smoke sucks straight up the chimney and fire starts easily with no lingering smoke in the box. I should also mention, we have numerous carbon monoxide detectors throughout the house, as, I would recommend anyone with a wood stove install. Actually, they should be installed with or without a wood stove, it's just smart.

 

I also was beginning to question the cat. I took several videos and showed them to the dealer yesterday. He assured me that my cat had every indication of a perfectly functioning cat. I'm still thinking about replacing it anyways. Delima now is, I'm not smelling smoke. If I do, that's next.

 

To give an idea of my start from coals this evening, here is a picture. Two small 3" splits with a handful of kindling on top. Notice, good draft, no lingering/spilling smoke.

Nine minutes after starting, cat is in active range. Closed bypass and dialed back the stat a 1/4". This will give me a nice pile of coals in a couple hours to load my overnight onto.

 

Possible update. Last night, I walked into my utility room, and the smell of smoke was very distinct. I threw my jacket on went outside and looked. Sure enough, the breeze had thin smoke lightly blowing towards the exhaust pipe for the hot water heater. With the breeze directly out of the east, that would make any smell exiting the chimney, run the full length of the peak of the house, which I wonder, could there be some smell coming in to the attic through the ridge vent. When I felt the exhaust pipe on the propane hot water heater, it was cold inside the house, so I wonder if any smell could be coming in through there, especially if the stove was trying to draw any outside air. I do not have an outside air kit on the stove, and with its placement in the house, am unable to install one. The fire was just getting established at that time, so there was more smoke than typical. I am still leaning towards replacing the cat.

 

Standing pilot type water heater?

 

Yes, that is what it is.

 

So if you lay your hand on the flue pipe right above the water heater hood, it's not even sorta warm? Normally they are...there's always a draft maintained by the pilot flame, or at least there should be.
Might be a good area for a co alarm.
I just had an issue at work here in the last few weeks where the water heater would go out randomly...turns out someone kept turning on a vent fan, but windows that are always open in warmer weather were shut, so it put a negative pressure on the building and was sucking in through the furnace/water heater flue.
Flame rollout switch did it's job.

 

Sorry, I misspoke. When I said "cold", I meant it was not really hot like it is after heating the water. You could hold your hand on it and it was barely warm. I have a CO2 detector 3 feet from the HWH, as well as several others throughout the house. Very good point though and pretty crazy what you had happen at work.

 

I forgot the other part of the story...it was reported that the door between the room with the vent fan, and the room with the water heater/furnace needed a new door closer, as the door would not latch unless you pulled it shut.
Yup, you guessed it, the fan was keeping it open! Fixed it with the flip of a switch!