Keystone cat probe=flue thermo??

[Woody Stover]

Last night I installed the cat probe that I got from Woodstock. I lit a load of Cherry and gave it air to get it going, and before long the probe was reading 1000*. When I later closed the bypass and the combustor lit off, the temp on the probe dropped to below 800*! Whaaat?? I'm used to the probe on the Dutchwest 2460, which is mounted on the top plate of the stove and hangs down right above the combustor. It can be used to tell you when to engage, and once the combustor is lit, will go to 1100-1200* in fairly short order. This Keystone probe seems to be useful only as a flue temp indicator. It does respond much quicker to air adjustments than the surface thermo that I've got lying on top of the tee snout close to the flue outlet, so that's informative. The probe comes with a magnet that I assume is to hold it in place and keep it from flopping around inside the stove, since the hole in the stove doesn't hold the probe shaft tightly. I thought that if I didn't use the magnet, the probe tip would be closer to the cat and give me better readings. When I tried this the temp came up a little, to around 900*, but nowhere near the temp that the cat is burning at, I don't believe.
I recall a recent thread where someone (Todd or Bill, I think) said that the probe tip on the Woodstocks "wasn't close enough to the cat" and I've seen posts about drilling a hole in the top to get the probe in a better position. I don't know that I'll do that; I can tell when to close the bypass by the stovetop meter and how the fire is burning. I'll probably just leave the probe where it is to give me feedback on firebox temps and how air adjustments are affecting them. Just not what I was expecting when I spent money on the cat probe...

 

[Todd]

I my opinion that rear hole set up isn't the most accurate. It's off to the side of the cat and probably isn't close enough. When you had the bypass open it was probably reading the direct flames going up the flue since the probe is right next to it.

I drilled down through the top plate and got my probe 1" from the cat. I've seen temps as high as 1700 with a full load of Oak. It also shoots up quickly over 1000 the first few minutes after engaging.

 

[Todd]

Woody,
How long is that probe? have you checked to see how close it is to the cat? If you do decide to drill down through the top like me you can cut the probe you have down to the required size. I have the 2" dial with 3" probe.

So far I've been able to engage from a cold start in 15-20 minutes relying on the probe temps. The stove top lags way behind and can be as low as 150 while the probe is well over 500.

 

[Woody Stover]

Woody,
How long is that probe? have you checked to see how close it is to the cat? If you do decide to drill down through the top like me you can cut the probe you have down to the required size. I have the 2" dial with 3" probe.

So far I've been able to engage from a cold start in 15-20 minutes relying on the probe temps. The stove top lags way behind and can be as low as 150 while the probe is well over 500.

They sent me the 2" face, 8" probe. I haven't taken the top cover off yet to look at where the probe tip is but when I had the magnet off I felt it hitting something...maybe the combustor frame?
15-20 min? Wow! I've tried to engage earlier than 250 stove top...I can generally light it off at 230. You're not afraid to fire your stove up, and you're already using the stainless cat if I'm not mistaken. I'm getting more used to putting the heat to it and not worrying if the expanded metal or the scoop glow a little bit. I have to watch my flue temp though. Had it up to about 700 on a surface thermo on the tee snout and the tee started to glow where the heat coming through the snout slams into the vertical part of the tee. I've got the stainless cat and scoop, but I think I'll use the original ceramic cat for a while to see how the two compare. I'm still learning to run the stove. A couple of nights ago I started a fire, engaged and gave it more air to have some flame in the box and see if I could get the stove top over 500, and the stove cranking out big heat. I went outside and to my dismay saw smoke out of the stack. I ended up stalling the cat and had a hard time getting it relit even though the stove top was at 375. Maybe I had too much wood off-gassing from the brisk fire I had going at startup, and opening the air up didn't give the combustor enough time (the third T.) Tonight I let the fire settle in after engaging, gave it slightly more air, and it continued to burn clean with flames in the box...no smoke out of the flue. I've now got the air open slightly above 1 and have got decent flames. Stove top just crested 400. Hmmm, now the combustor is out, brisk flames and no smoke outside. Live and learn. :lol: I'm still baffled as to how you and other Woodstock burners are getting these high stove top temps, and am curious as to how much smoke you're getting out of the stack when you are cranking your stoves.
Anyway, I was thinking maybe it would be possible to bend the probe to get the tip behind the combustor, or is the probe steel too hard to bend. I thought maybe a longer probe would get the tip closer to the combustor if I could bend it, but the longest probe I see on the condar site is a 6.5", not even the 8" that I have. But why is this sold as a cat thermometer? Surely they know it doesn't work, don't they?
How about the Fireview? I replace the door, combustor, bypass gaskets and installed the steel cat and scoop on my SIL's. I forgot to bring the probe with me, however. I noticed that the hole for the probe is on the opposite side of where the Keystone's is. Is it in a better position to give an actual cat temp reading?
Bad news for me, though...gaskets didn't help all that much with the Fireview air leaks. 22' stack and with the air set on 0 and key damper closed, there's still flame in the firebox. Talking to her yesterday, we got on the subject of backpuffs, and she said that in the past when she's had one (seldom,) smoke came out the edges of the cast front plate that holds the glass. Could be a big air leak there. Anyone know if this is a piece that can be removed without taking the stove apart? I'm assuming that this stove is mostly gasketed construction...is that right? When I ordered the parts from Woodstock, the person I talked to told me "No, we don't have a 'build manual' available." Guess I will have to talk to Vaughn. I can't rebuild that stove now anyway...it's almost Winter. Next up is rebuilding my DW 2460...

Well, I'm sure that whoever is still reading this rambling stream of stove consciousness post is glazing over by now. But I doubt that anyone has made it this far. :lol:
I'm going outside to split some Sugar Maple!

 

[Todd]

Lots to absorb there Woody. Sounds to me like your air settings are a little high if your seeing 700 on your tee snout and seeing some smoke. I pretty much run mine around #1. A little lower gives me those floating flames with a nice red cat which Woodstock says is the most efficient burn. If I go too low the flames snuff out and the stove top temps can get well over 600 due to the cat gorging itself on smoke. When I burn over #1 I get a good box burn with planty of flame and red coals, I think this gives the most heat because it warms up the whole stove verses just the top with a low burn. There is a point at when there is too much draft running through that cat and it can't keep up with burning the smoke, for me it seems to be about 1.5. Your going to have to play around with the settings and watch the temps and chimney to find your sweet spots. I've also seen stalls if I turn it down too soon so I tend to engage at a higher setting and letting it burn for awhile before turning it down.

Lately I've been tinkering with the air wash and that extra combustion air hole in the ash pan to see if I can get more control. I'm starting to think I have too much draft with this new Supaflue chimney and I'm getting a strong left to right burn at higher air settings. When I turn it down it burns through the middle and leaves chunks on the sides. Plugging that hole seems to give me a more even fire box burn.

Your SIL Fireview sounds like it has a leak somewhere and maybe you need to change out the glass gasket, they do have instructions for this. Also check your air wash plate for proper gap, should be 1/4". Oh, one other thing to check is the air setting slide, mine was off track the first year and I was also burning at 0 for the whole year til I figured it out. I might of got bumped off track during shipping, it's an easy fix by pushing a screwdriver up in there to slide it back in place.

 

[Todd]

I would call Condar about bending that probe, they should know. I think the Woodstock cat probe was designed for their older model stoves and they never canged the castings or hole potisions. I know if you look at the Classic the baffle and cat are different and the probe would insert directly in front of the cat, the older 201 Fireview was set up the same way and the new 205 model baffle and cat are completely different. I have no idea what the older Keystone looked like on the inside but looking at the hole for the cat probe I'm betting the cat was more on the right side over the door?

 

[raybonz]

I my opinion that rear hole set up isn't the most accurate. It's off to the side of the cat and probably isn't close enough. When you had the bypass open it was probably reading the direct flames going up the flue since the probe is right next to it.

I drilled down through the top plate and got my probe 1" from the cat. I've seen temps as high as 1700 with a full load of Oak. It also shoots up quickly over 1000 the first few minutes after engaging.

Nice work on the cat probe install Todd.. Woodstock should do exactly what you did on all their stoves! Cat probes should be standard equipment on any cat stove..

Ray

 

[Woody Stover]

Now I have gotten 500 on the cat stone, when I had 450 on the spot where I normally keep the thermo...on the back inner corner of one of the side stones.
Wow, I didn't even know about the ash pan vent hole!
I noticed a slight left to right burn, but I recently adjusted the air wash to 1/4"...left side was definitely wider than that. I've got about 17' of insulated 6" stack. Not seeing excessive draft on this setup, but I don't have to open the air too far above 0 to get flame. How tall is your Supaflue stack?
As for the Fireview, I think it's time to break out the incense stick and try to find the biggest air leaks...
I didn't look at the airwash but if it's similar to the Keystone, I'd think that an adjustment there would only affect the balance of air directed at the window versus the air that comes out the holes toward the combustor, and not the total amount of air entering the stove, right?

Woodstock should do exactly what you did on all their stoves

The plain stone top sure is purty but that wouldn't stop me from dropping a probe in there; I'm a 'function over form' guy for the most part...

 

[Todd]

My Supaflue is a little over 20', it definitely drafts better than my old 5.5 s/s liner. I keep tweaking the air down further and further as the weather gets colder.

I've noticed quite a few Keystone owners that have adjusted that dang air wash plate. I think Woodstock just assumes the plate is square and throw it in there without measuring the gap. I've had to adjust both of mine and if you take the plate out and look at them they aren't square and have a somewhat wavy edge. I've been tinkering with my basement stove because it burns left to right especially at higher burn rates, it seems to even out better with a low burn.

Don't forget to check the back of the stove where the air regulator slide is on your sil Fireview, just might be the problem.They have been known to jump off track.

 

[raybonz]

Now I have gotten 500 on the cat stone, when I had 450 on the spot where I normally keep the thermo...on the back inner corner of one of the side stones.
Wow, I didn't even know about the ash pan vent hole!
I noticed a slight left to right burn, but I recently adjusted the air wash to 1/4"...left side was definitely wider than that. I've got about 17' of insulated 6" stack. Not seeing excessive draft on this setup, but I don't have to open the air too far above 0 to get flame. How tall is your Supaflue stack?
As for the Fireview, I think it's time to break out the incense stick and try to find the biggest air leaks...
I didn't look at the airwash but if it's similar to the Keystone, I'd think that an adjustment there would only affect the balance of air directed at the window versus the air that comes out the holes toward the combustor, and not the total amount of air entering the stove, right?

Woodstock should do exactly what you did on all their stoves

The plain stone top sure is purty but that wouldn't stop me from dropping a probe in there; I'm a 'function over form' guy for the most part...

The cat probe is essential to running a cat stove and keeps you informed so it isn't a luxury item but a gauge to proper stove operation.. My CDW came with one and I used it every day..

Ray

 

[Todd]

Now I have gotten 500 on the cat stone, when I had 450 on the spot where I normally keep the thermo...on the back inner corner of one of the side stones.
Wow, I didn't even know about the ash pan vent hole!
I noticed a slight left to right burn, but I recently adjusted the air wash to 1/4"...left side was definitely wider than that. I've got about 17' of insulated 6" stack. Not seeing excessive draft on this setup, but I don't have to open the air too far above 0 to get flame. How tall is your Supaflue stack?
As for the Fireview, I think it's time to break out the incense stick and try to find the biggest air leaks...
I didn't look at the airwash but if it's similar to the Keystone, I'd think that an adjustment there would only affect the balance of air directed at the window versus the air that comes out the holes toward the combustor, and not the total amount of air entering the stove, right?

Woodstock should do exactly what you did on all their stoves

The plain stone top sure is purty but that wouldn't stop me from dropping a probe in there; I'm a 'function over form' guy for the most part...

The cat probe is essential to running a cat stove and keeps you informed so it isn't a luxury item but a gauge to proper stove operation.. My CDW came with one and I used it every day..

Ray

I agree, I'm finding it a very good tool and may just toss the stove top thermometer once I get more familiar with the cat probe.

 

[Woody Stover]

Don't forget to check the back of the stove where the air regulator slide is on your sil Fireview, just might be the problem.They have been known to jump off track.

I know it isn't running on 0 like yours was. The slide definitely gives more or less air. Doesn't mean there's not a problem there, though. I will check it for sure. That's the kind of easy fix I'm hoping for.
:lol: