Ashford 20.2 Thermostat Issues

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sprucebeetleburner

New Member
Dec 5, 2021
5
Yukon
First time poster, long time lurker. I drew on these forums heavily when it came time to pick and install a setup last autumn.

I have an 2020 Ashford 20.2, with 8 feet of double wall, and 10 ft of Excel chimney on top of that. Flue temp thermometer 18" above the stove. No OAK. I burn mostly beetle kill spruce. I don't have a moisture meter but most everything I cut is long dead dried standing dead. I live in a part of the Yukon with a climate similar to Fairbanks (ie -40 right now)

The stove has always performed well, until last week when I came home from being out of town for a week, and noticed that at full open on the thermostat, I wasn't getting the fire intensity I was used to. At full open, bypass open and a full load of wood, flue temps would top around 700 and it didn't have the characteristic 'roar' of a new fire. Ever since, I've noticed my thermostat is behaving erratically. I feel like I can't turn the stove down as much as I used to (there's flame at the lowest setting).

The kicker for me was last night, when I reloaded, the flue temps rocketed up. With the bypass open, I started turning the thermostat down at 800 degrees, but temps climbed all the way to 1200 before coming back down. Then when I turned the thermostat down, it rotated past the 12o clock position and over to about 7 o clock. So high on the thermostat is now 6 o clock, and low is rotated all the way around at 7 o clock. It hits a stop at both min. and max. AFAIK it's only ever rotated between 6(high) and 12(low) before last night. The knob is still securely attached and rotating the rod.

Something feels off to me with the thermostat control. I plan to call blaze king tomorrow but given it's -40, I'd love to fire it back up today, although after last nights brief but intense fire, and the inconsistency with thermostat settings I'm feeling tentative. Door gasket is tight. Am I missing a variable here? Thoughts?
 

stoveliker

Minister of Fire
Nov 17, 2019
6,165
Long Island NY
Likely the set screw of the dial on the rod is loose. Call BK, they'll walk you thru how to fix that. It is simple. (I've not done this myself yet, so I'll refrain from explaining the exact steps.)
 

Highbeam

Minister of Fire
Dec 28, 2006
19,986
Mt. Rainier Foothills, WA
First time poster, long time lurker. I drew on these forums heavily when it came time to pick and install a setup last autumn.

I have an 2020 Ashford 20.2, with 8 feet of double wall, and 10 ft of Excel chimney on top of that. Flue temp thermometer 18" above the stove. No OAK. I burn mostly beetle kill spruce. I don't have a moisture meter but most everything I cut is long dead dried standing dead. I live in a part of the Yukon with a climate similar to Fairbanks (ie -40 right now)

The stove has always performed well, until last week when I came home from being out of town for a week, and noticed that at full open on the thermostat, I wasn't getting the fire intensity I was used to. At full open, bypass open and a full load of wood, flue temps would top around 700 and it didn't have the characteristic 'roar' of a new fire. Ever since, I've noticed my thermostat is behaving erratically. I feel like I can't turn the stove down as much as I used to (there's flame at the lowest setting).

The kicker for me was last night, when I reloaded, the flue temps rocketed up. With the bypass open, I started turning the thermostat down at 800 degrees, but temps climbed all the way to 1200 before coming back down. Then when I turned the thermostat down, it rotated past the 12o clock position and over to about 7 o clock. So high on the thermostat is now 6 o clock, and low is rotated all the way around at 7 o clock. It hits a stop at both min. and max. AFAIK it's only ever rotated between 6(high) and 12(low) before last night. The knob is still securely attached and rotating the rod.

Something feels off to me with the thermostat control. I plan to call blaze king tomorrow but given it's -40, I'd love to fire it back up today, although after last nights brief but intense fire, and the inconsistency with thermostat settings I'm feeling tentative. Door gasket is tight. Am I missing a variable here? Thoughts?

With strong draft (due to cold) and evergreens it’s really easy to overtemp the flue before the stove heats up enough to make the thermostat close.
 

stoveliker

Minister of Fire
Nov 17, 2019
6,165
Long Island NY
That doesn't explain the "past 12 o'clock" closing the Tstat. Something is loose here.
 

sprucebeetleburner

New Member
Dec 5, 2021
5
Yukon
Appreciate the thoughts. Stoveliker, are you talking about the set screw on the knob itself? Watching the little bit of rod behind the knob that I can see, the connection between the knob and rod is solid. They both rotate together through the entire range from 6 o clock(high) to 7 o clock(low).
 

stoveliker

Minister of Fire
Nov 17, 2019
6,165
Long Island NY
Yes I was. Ok. That's not it..

But if your minimum is now at a different position, something mechanical is loose. Easiest would have been the set screw. Maybe it's something inside.

@BKVP?
 

Highbeam

Minister of Fire
Dec 28, 2006
19,986
Mt. Rainier Foothills, WA
That doesn't explain the "past 12 o'clock" closing the Tstat. Something is loose here.

That’s totally normal. The hard stop is full cw hot at 6 o’clock. You can wind it way back ccw cold past 12 o’clock.

Go try yours. Report back with your ccw rotation range.
 

stoveliker

Minister of Fire
Nov 17, 2019
6,165
Long Island NY
I can't. And the op stated he couldn't either, initially.

Something mechanically changed here, if I read the first post correctly.
 

BKVP

Minister of Fire
Ok, turn the black knob clockwise until it stops. Now, loosen the set screw with a 5/64" Allen wrench. Continue turning clockwise until white line on knob points at 6 o'clock. You may be turning it nearly 360 degrees. Now tighten the screw. The effective range of operating is about 2:30-6. Any counterclockwise more that 2:30, has zero effect.
Also grab the knob and try and move it in and out (with set screw very secre). There should be very little movement in or out. If this all checks out, your thermostat is 99% certain not the issue.

Make certain the bypass is closing. Without a fire and using a flashlight, look inside as someone moves the bypass handle. The plate should lift and close securely. If all good, look at your combustor. Remove flame shield (no tools needed!) it just lifts up, lift off tabs and drop down. Pay attention to orientation as there is an up and down side. If combustor is clear, reinstall flame shield.

Lastly, check the cap and chimney system.

If any of this turns out to be an issue, call your dealer, unless chimney needs cleaning, then call a sweep.

BKVP
 

sprucebeetleburner

New Member
Dec 5, 2021
5
Yukon
Very, very slight play in the thermostat knob but if I had to put a number on it I'd say 1/32" so probably no issue there. The knob is already at the 6 o clock position when I turn to clockwise, so nothing to do there either. Flame shield and cat look good. Bypass is working nicely.

Is it possible that the strong draft due to cold is making the fire burn hotter at low setting/ bypass closed, as well as making it burn voraciously during startup/bypass open?

It's supposed to warm up quite a bit to -10 tomorrow, I'll see how she burns with the warmer temps.
 
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BKVP

Minister of Fire
Very, very slight play in the thermostat knob but if I had to put a number on it I'd say 1/32" so probably no issue there. The knob is already at the 6 o clock position when I turn to clockwise, so nothing to do there either. Flame shield and cat look good. Bypass is working nicely.

Is it possible that the strong draft due to cold is making the fire burn hotter at low setting/ bypass closed, as well as making it burn voraciously during startup/bypass open?

It's supposed to warm up quite a bit to -10 tomorrow, I'll see how she burns with the warmer temps.
Excessively strong draft can change how a stove performs one day to the next. Depending upon the cap (to some degree) high winds can also effect performance.
 

kennyp2339

Minister of Fire
Feb 16, 2014
6,693
07462
@Poindexter can chime in here if it isnt the a t-stat or excessive draft. A few years back he got into making kilns and effectively did to good of a job as his wood was very dry, I remember hearing about erratic fires from not enough umphh to, to much, turns out burning 12% soft wood was off gassing way to fast and creating erratic burning conditions.
 

Highbeam

Minister of Fire
Dec 28, 2006
19,986
Mt. Rainier Foothills, WA
Is it possible that the strong draft due to cold is making the fire burn hotter at low setting/ bypass closed, as well as making it burn voraciously during startup/bypass open?

It's supposed to warm up quite a bit to -10 tomorrow, I'll see how she burns with the warmer temps.

I notice this a lot. I burn when it's 60 outside and also when it is 7 degrees. Big difference in how the stronger draft from the outdoor cold effects the output my low burn setting. It's actually kind of nice, burns a bit hotter when I need more heat.

Oh and I checked last night, my thermostat knob turns way past 12 o'clock. The flapper clacks shut at about 2 o'clock but you can keep turning CCW way past noon. I start feeling a bit of tension/resistance at about 10 o'clock and I don't want to boof the bimettalic coil spring.
 

sprucebeetleburner

New Member
Dec 5, 2021
5
Yukon
Glad to hear yours turns far CCW too highbeam

I spoke with my local dealer on the phone today and they walked me through removing the thermostat cover and having a look at the flapper. I'm not sure why the knob ever would've ever stopped at the 12 o clock position but it's clear that it bottoms out on a stop at the 7 o clock position. That said, after actually watching the flapper, what everyone says is true: rotating CCW past the 2 o clock position doesn't really do anything anyways.

I still feel like the stove used to burn lower with the flapper closed however. Outdoor temps have warmed to ~minus 10. With the stove all the way turned down and cat engaged, flue temps are 400 degrees which is somewhat higher than blaze king advertises (150-300). My cat probe typically sits somewhere around 10 o clock-noon.

Thanks for bearing with me, still trying to get the hang of burning with a cat.
 

BKVP

Minister of Fire
Glad to hear yours turns far CCW too highbeam

I spoke with my local dealer on the phone today and they walked me through removing the thermostat cover and having a look at the flapper. I'm not sure why the knob ever would've ever stopped at the 12 o clock position but it's clear that it bottoms out on a stop at the 7 o clock position. That said, after actually watching the flapper, what everyone says is true: rotating CCW past the 2 o clock position doesn't really do anything anyways.

I still feel like the stove used to burn lower with the flapper closed however. Outdoor temps have warmed to ~minus 10. With the stove all the way turned down and cat engaged, flue temps are 400 degrees which is somewhat higher than blaze king advertises (150-300). My cat probe typically sits somewhere around 10 o clock-noon.

Thanks for bearing with me, still trying to get the hang of burning with a cat.
Two things, stack gauges are not scientific, super precise instruments.

Second, readings will vary some depending upon where they are taken.

You'll get the hang of it...just a bit of a learning curve.

Stay warm.

BKVP
 

Poindexter

Minister of Fire
Jun 28, 2014
2,814
Fairbanks, Alaska
I hadn't opened this thread before I was tagged as I have never used a 20 box. I mean, I have seen them at the store but I have never lit a fire in one.

As the thread was developing, my thoughts were, possible loose thermostat doohickey, increased draft because of colder outdoor ambient temperatures, possible leak where the bypass door is supposed to seal and possible fly ash on the cat face.

Dry wood, say 13% and under makes a LOT of fly ash in my 30 box. Another user here has observed in the past that having a whole lot of draft can increase fly ash accumulation on the combustor face also.

I did brush my pipe in the last week or so, we were having a burn ban here and the stove was cold. I did spend some extra time on the cap area. I brush bottom up, so with the brush all the way up in the cap and grating I spent some extra time on the twist twist and the to and fro up there. I don't know that I have ever had a problem with what I would think of as an outlet obstruction, but it does come up frequently here so I went ahead and spent a little extra time on it. I can't say I got any extra crud out, but one less thing to worry about in the meantime.

With the thermostat checked out and the combustor face inspected, if it were my stove I would want to do a dollar bill test on the bypass door/ bypass gasket the next time the stove is cold. Visible flame with the bypass door cammed fully over and the thermostat on a low setting to me says either extremely dry wood, or an airleak in the bypass door gasket. An american dollar should be able to be torn in half when it is clamped in the bypass door/gasket, full circumference. Could be a leak in the loading door gasket, but OP said he checked and the knife edge on the loading door is a fairly robust. Dunno about Canadian paper money in the door gaskets, haven't handled any in decades.

Also, a moisture meter. If @sprucebeetleburner cracks open a split and measures parallel to the grain, about the middle of the length and down near the bark on the freshly exposed face, what does a moisture meter read when the wood is at +55 to +70 degrees F? About 13 to 21 C. Bring some pieces indoors for a couple or three days before measuring. You don't have to buy a meter, I think your fuel is plenty dry, my question is how dry. If you have a friend with a meter just check 3-4 pieces and buy him a taco. If it is down around 6-8% fuel, he could see flame with no airleaks and the Tstat on a low setting. Maybe. In my 30 box I would expect to.

The killing beetles are just entering the area near me, OP might have some fuel that is problematically dry.
 

BKVP

Minister of Fire
Check to make certain ash plug is sealed snug. Good reason to leave some ash in the bottom when cleaning out...and help protect the bricks too.
 

Highbeam

Minister of Fire
Dec 28, 2006
19,986
Mt. Rainier Foothills, WA
Glad to hear yours turns far CCW too highbeam

I spoke with my local dealer on the phone today and they walked me through removing the thermostat cover and having a look at the flapper. I'm not sure why the knob ever would've ever stopped at the 12 o clock position but it's clear that it bottoms out on a stop at the 7 o clock position. That said, after actually watching the flapper, what everyone says is true: rotating CCW past the 2 o clock position doesn't really do anything anyways.

I still feel like the stove used to burn lower with the flapper closed however. Outdoor temps have warmed to ~minus 10. With the stove all the way turned down and cat engaged, flue temps are 400 degrees which is somewhat higher than blaze king advertises (150-300). My cat probe typically sits somewhere around 10 o clock-noon.

Thanks for bearing with me, still trying to get the hang of burning with a cat.

My flue temps are almost always at 400 during the long and low cruise in my double wall pipe. Temperatures are measured with a condar probe meter which while slow to react, tested to be very accurate against an electronic thermocouple device that is extremely accurate and fast.

I can force the flue temps lower by lowering the thermostat farther than I'd like and flirting with cat stall. Doing this increases the likelihood of creosote accumulation in the flue and of course increases the chance of a full stall. I like the cat to stay hotter and the flue temperatures to stay in the normal range above 400.

Yes, it is possible to run flue temps down in the 150-300 area but I prefer a slightly higher output level.
 

sprucebeetleburner

New Member
Dec 5, 2021
5
Yukon
I'll try and see if I can track down a moisture metre around here. Too dry a wood would be a unique problem for sure, but leave it to a huge beetle outbreak that's been largely unharvested, and ongoing for 30 years to lend some dry wood.

I checked the bypass door, even found an American dollar to try with and it feels nice and tight.

I pulled the flame shield and noticed that the cat was sticking proud of where it seems like should sit. Maybe 1/2-5/8" forward. A very gentle press moves the cat around. I always imagined it was sealed tight in place so I'm surprised it has movement. Seems like the movement inside of the frame. The rope around it also doesn't look fantastic. Are cracks in that rope normal? Looks like a few tears/cracks in it.
 

BKVP

Minister of Fire
I'll try and see if I can track down a moisture metre around here. Too dry a wood would be a unique problem for sure, but leave it to a huge beetle outbreak that's been largely unharvested, and ongoing for 30 years to lend some dry wood.

I checked the bypass door, even found an American dollar to try with and it feels nice and tight.

I pulled the flame shield and noticed that the cat was sticking proud of where it seems like should sit. Maybe 1/2-5/8" forward. A very gentle press moves the cat around. I always imagined it was sealed tight in place so I'm surprised it has movement. Seems like the movement inside of the frame. The rope around it also doesn't look fantastic. Are cracks in that rope normal? Looks like a few tears/cracks in it.
It's possible it moved forward in shipping or installation, that is why we secure it with a string. If you were able to push it in, that should do. However, your dealer can order replacement gasket if you like...at no charge.
 

moresnow

Minister of Fire
Jan 13, 2015
2,073
Iowa
I burn the 20 series. I've had the cat migrate forward a little a few times. Never more than a 1/8th to maybe close to a 1/4. The gasket will be imperfect on mine also.
Occasionally strong wind and real cold temps will affect the close down affect when turning down the therm knob. For instance, if you have those conditions and you are having a tough time snuffing the active flame. My suggestion is to twist the knob to wide open. Wait a minute. Then. Twist the knob ccw at a swifter than normal pace. Tink. Closed. It seems to always work.
If I twist the knob ccw slowly for keeping an active flame for a while on a fresh load, or running the stove hot for a while it sometimes needs the method described. Almost like a reset. Dunno. Worth a try.

I am burning some exceptionally dry wood that almost starts before it gets in the stove;lol No irregular burn symptoms that I have encountered. Maybe lucky?

Let us know what you figure out.