CAT thermometer Question

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DWIGHTTBP

Member
Nov 3, 2012
14
Hi-- I just replaced our original CAT thermometer for the Princess (PE-1006) wood stove we've had for about ten years (new thermometer from 'Stove & Grill Parts For Less').

At room temp the new thermometer's gauge sits just below 9 o'clock on the dial, just at the beginning of where the inactive zone is indicated on the dial. On our original thermometer at room temp, the temp gauge sits at about 6 o'clock on the dial, far below where the inactive zone is indicated on the dial.

Can someone please confirm for me that the gauge on the new thermometer is located in the correct position at room temp? And that our original thermometer had lost its original calibration? I don't recall that the temp gauge on our original thermometer was ever not at about the 6 o'clock position at room temp but can't be sure since it's been so long!

I'm asking mainly because I'm seeing that with the new thermometer, we can close the bypass much sooner than we've been able to since the new thermometer indicates our fires getting into the active zone relatively quickly--and when I close the bypass and let the fire burn on high for the recommended 20-30 min, the gauge can easily go way past to the active zone to the 6, 8 or even almost to the 9 o'clock position on the thermometer. Which indicates overfiring, right?

So, with the new thermometer I'm assuming we should be firing our stove on high with each new load of firewood (following recommended procedures) for 20-30 minutes OR until the temp gauge gets to the top of the active zone, whichever comes first? Even when the stove was very hot, our original thermometer's temp gauge never went past the end of the active zone.

Thanks for any clarification anyone can offer. If this new thermometer is accurate, it's making us realize we've been overfiring our stove and losing efficiency over the time the old thermometer was likely giving us inaccurate readings!

Also: When we first got our Blaze King stove, it was pretty easy to call someone at Blaze King and talk to them about any questions we had. That doesn't seem to be the case any more. I can't even email them (email returned as undeliverable) or contact them via their online contact form (always tells me a required field is missing when it's not (checked/re-checked many, many times!)). Have others noticed this change? Or have any tips for getting a hold of them?

Thanks!
 

stoveliker

Minister of Fire
Nov 17, 2019
7,262
Long Island NY
@BKVP
Is on here and quite active.

Undeliverable email suggests a different email address should be used.

Why do you think your old gauge was out of calibration?

6 o'clock depends on what you define ad "noon"...
 

DWIGHTTBP

Member
Nov 3, 2012
14
@BKVP
Is on here and quite active.

Undeliverable email suggests a different email address should be used.

Why do you think your old gauge was out of calibration?

6 o'clock depends on what you define ad "noon"...

Hi- thanks for the quick reply. See images below. Top image is the original thermometer at room temp. Below that is the new thermometer at room temp. I'm just confused about the big difference between the two and assume the new thermometer is correct and the old one has become inaccurate over time. But I'm asking the questions I've asked because I'm not sure. It obviously makes a huge difference in being able to tell when to close the bypass...etc.

On the email, I got the email address from the BK web site so in theory it should work. I did not recall that I might be able to communicate directly with a BK rep through this forum (haven't been here in a long time), so thanks for that.


Old
BK CAT Thermometer Original.jpg


New
BK CAT Thermometer New.jpg
 

stoveliker

Minister of Fire
Nov 17, 2019
7,262
Long Island NY
Ok. I had the impression you had bought "a" cat gauge elsewhere and was comparing their indicators.

Yes, from what I have seen the old gauge is likely off. You might be able to reset it by loosening the nut and turning the needle to the same place as the new one. Or just use the new one.

The cat gauge though does not indicate overfiring of the firebox. Having it like the old one could mean you heated the cat beyond what is needed before closing the bypass. If the cat still behaves like it should (as seen with the new gauge) I think you may have wastednsome heat but the cat could still be okay.

The email has to be resolved by BK themselves :)
 

BKVP

Minister of Fire
Hi-- I just replaced our original CAT thermometer for the Princess (PE-1006) wood stove we've had for about ten years (new thermometer from 'Stove & Grill Parts For Less').

At room temp the new thermometer's gauge sits just below 9 o'clock on the dial, just at the beginning of where the inactive zone is indicated on the dial. On our original thermometer at room temp, the temp gauge sits at about 6 o'clock on the dial, far below where the inactive zone is indicated on the dial.

Can someone please confirm for me that the gauge on the new thermometer is located in the correct position at room temp? And that our original thermometer had lost its original calibration? I don't recall that the temp gauge on our original thermometer was ever not at about the 6 o'clock position at room temp but can't be sure since it's been so long!

I'm asking mainly because I'm seeing that with the new thermometer, we can close the bypass much sooner than we've been able to since the new thermometer indicates our fires getting into the active zone relatively quickly--and when I close the bypass and let the fire burn on high for the recommended 20-30 min, the gauge can easily go way past to the active zone to the 6, 8 or even almost to the 9 o'clock position on the thermometer. Which indicates overfiring, right?

So, with the new thermometer I'm assuming we should be firing our stove on high with each new load of firewood (following recommended procedures) for 20-30 minutes OR until the temp gauge gets to the top of the active zone, whichever comes first? Even when the stove was very hot, our original thermometer's temp gauge never went past the end of the active zone.

Thanks for any clarification anyone can offer. If this new thermometer is accurate, it's making us realize we've been overfiring our stove and losing efficiency over the time the old thermometer was likely giving us inaccurate readings!

Also: When we first got our Blaze King stove, it was pretty easy to call someone at Blaze King and talk to them about any questions we had. That doesn't seem to be the case any more. I can't even email them (email returned as undeliverable) or contact them via their online contact form (always tells me a required field is missing when it's not (checked/re-checked many, many times!)). Have others noticed this change? Or have any tips for getting a hold of them?

Thanks!
We haven't gone away....or changed policies. You can call 509-522-2730 8-5 M-F. We are extremely busy, but you will be helped.
 

Highbeam

Minister of Fire
Dec 28, 2006
20,376
Mt. Rainier Foothills, WA
Ok. I had the impression you had bought "a" cat gauge elsewhere and was comparing their indicators.

Yes, from what I have seen the old gauge is likely off. You might be able to reset it by loosening the nut and turning the needle to the same place as the new one. Or just use the new one.

The cat gauge though does not indicate overfiring of the firebox. Having it like the old one could mean you heated the cat beyond what is needed before closing the bypass. If the cat still behaves like it should (as seen with the new gauge) I think you may have wastednsome heat but the cat could still be okay.

The email has to be resolved by BK themselves :)
Neither meter is calibrated correctly. The cold meter reading should be at the little white tick at the bottom of the inactive scale.

The new meter is certainly closer.
 
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BKVP

Minister of Fire
Neither meter is calibrated correctly. The cold meter reading should be at the little white tick at the bottom of the inactive scale.

The new meter is certainly closer.
Correct. Loosen the 5/16" nut on the bottom very slightly. Rotate the gauge clockwise slowly...until needle points at white tick mark below inactive. Hold securely and tighten the nut.
 

stoveliker

Minister of Fire
Nov 17, 2019
7,262
Long Island NY
Neither meter is calibrated correctly. The cold meter reading should be at the little white tick at the bottom of the inactive scale.

The new meter is certainly closer.
My BK meter is also not at the tick at the bottom of the inactive range. It was at some random place below that.

I think none of these meters are. I wonder if BK does quality control on them as I've heard more stories about them being off. Obviously BK gets them from (Condar?) - but they may need better quality control checks to reach the level of quality of the stove...

I'll check and fix it when I get home from work travel this weekend.
 
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Highbeam

Minister of Fire
Dec 28, 2006
20,376
Mt. Rainier Foothills, WA
My BK meter is also not at the tick at the bottom of the inactive range. It was at some random place below that.

I think none of these meters are. I wonder if BK does quality control on them as I've heard more stories about them being off. Obviously BK gets them from (Condar?) - but they may need better quality control checks to reach the level of quality of the stove...

I'll check and fix it when I get home from work travel this weekend.
Be careful, I broke the bimetallic spring on one by calibrating it. Or perhaps it lost calibration because the spring broke. Just be careful.
 
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Nov 9, 2021
92
NH
Correct. Loosen the 5/16" nut on the bottom very slightly. Rotate the gauge clockwise slowly...until needle points at white tick mark below inactive. Hold securely and tighten the nut.
This is interesting, my relatively new PE32 has always indicated the same position at room temperature as the OP's old gauge (pretty much straight down), so I've probably been waiting much too long to close my bypass as well. I'll have to adjust it next time I let the stove go cold.
 

Todd

Minister of Fire
Nov 19, 2005
9,937
NW Wisconsin
This is why these thermometers should have numbers on them, so they’re easier to calibrate. I recently bought a Condar flue probe that read 150 at room temp. After calibrating it it’s reading closely to my Auber thermocouple, just a little slower to react.
 
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DWIGHTTBP

Member
Nov 3, 2012
14
This is why these thermometers should have numbers on them, so they’re easier to calibrate. I recently bought a Condar flue probe that read 150 at room temp. After calibrating it it’s reading closely to my Auber thermocouple, just a little slower to react.
Thanks to everyone for your comments-- super helpful! I'll definitely recalibrate the thermometer. Carefully. And thank you BKVP for the BK contact number. I'll call when I have additional questions, and keep in mind how understandably busy you all are.

As for the other question, when starting a new fire, are you all doing a 20-30 min burn on high no matter what? Or do you turn down the stove when the temp gauge gets to the top of the active zone? Remember I said that if I let mine burn on high for just 15 min (or less), the temp gauge can go way past the highest active zone reading all the way to nearly where it started when it was cold. Seems like that's letting the stove get way too hot so I've been backing it off to prevent that from happening. Thanks again for all the help!
 

Stump shot

Member
Jan 15, 2014
70
Montana
On a cold stove this is what I do before engaging the cat. Flue probe 400` (internal), wood charred, and flame impingement on the flame shield. Engage the cat, then I will look at the cat and it should be glowing red on at least half of it and the cat gauge will be nowhere near active.
 

Highbeam

Minister of Fire
Dec 28, 2006
20,376
Mt. Rainier Foothills, WA
Thanks to everyone for your comments-- super helpful! I'll definitely recalibrate the thermometer. Carefully. And thank you BKVP for the BK contact number. I'll call when I have additional questions, and keep in mind how understandably busy you all are.

As for the other question, when starting a new fire, are you all doing a 20-30 min burn on high no matter what? Or do you turn down the stove when the temp gauge gets to the top of the active zone? Remember I said that if I let mine burn on high for just 15 min (or less), the temp gauge can go way past the highest active zone reading all the way to nearly where it started when it was cold. Seems like that's letting the stove get way too hot so I've been backing it off to prevent that from happening. Thanks again for all the help!
Absolutely not running 20-30 minutes on high. That overfires my flue with my dry Doug fir and also pegs the cat meter. Seems like a huge waste of fuel too. The manual says something like 20-30 minutes OR until the fire is well established right?
 

stoveliker

Minister of Fire
Nov 17, 2019
7,262
Long Island NY
Yes, that OR is in the manual.
I can tell you that 4 year old red oak also does not go for 20 minutes (with my chimney...). My flue temp gets too close to 1000 F then. Once it's all nicely burning, black, and even starts cracking perpendicular to the grain on the split side and radially on the cut side of the splits, it's well time to shut it down.
 

DWIGHTTBP

Member
Nov 3, 2012
14
Yes, I also see that important "... OR until the fire is well established" in the manual and am really following that guidance now. It's the next sentence in our original manual that I followed too closely for years: "It is good burning practice to burn the stove on high for 20-30 min after every refueling, this will help in cleaning off any residual build-ups and lessen the chance of accumulation."
 
Jun 23, 2019
35
Smoky Mts. of NC
I like to use the infrared thermometer 'gun' to check the stove top temp. When it's gone up 100* F is when I close the bypass damper.
On a cold start, this means closing it when stovetop is 170 or so. If it's a warm start (but inactive), say at 180 F, then I close it at 280.
If I don't get a glowing cat within seconds, it is within a few minutes.
 
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cr0

New Member
Mar 6, 2023
12
SE PA
Absolutely not running 20-30 minutes on high. That overfires my flue with my dry Doug fir and also pegs the cat meter. Seems like a huge waste of fuel too. The manual says something like 20-30 minutes OR until the fire is well established right?
Helpful replies on what is too long before closing the bypass. What about closing the bypass too soon?

I asked about this in another thread. It seems like generally it is not a big deal to close it a little too soon, as long as a fire is well established. Smoldering happens eventually with the thermostat turned down anyway, just want the cat to be hot enough to function while that's happening, right?
 

cr0

New Member
Mar 6, 2023
12
SE PA
Also as far as the cat glowing, it seems like that happens on and off, is that normal? The cat seems to be functioning in terms of greatly reducing smoke out the chimney. What I mean is, even when the firebox would be very hot, it seems like sometimes the cat is glowing (usually when it's ripping hot with many flames) and sometimes the cat is not glowing (when it's very hot but thermostat has tampered flames to a lower level or left it smoldering brightly).
 

stoveliker

Minister of Fire
Nov 17, 2019
7,262
Long Island NY
You'd have to define "too soon".

If the cat gauge is in the active zone, it's not too soon. So on a hot reload where the cat was still active, I close it after 1 minute of flames to empty out the cold air in the firebox from the open door.
As was said in the other thread, if the cat gauge is increasing, and nearly in the active zone, it's fine (imo) to close the bypass. The gauge runs at least 5 minutes behind reality anyway.

Finally, cat glowing off and on is normal. Many factors going into that (phase of the burn, how far the thermostat is open at that particular time, etc.).

As long as you can get a clean exhaust (only shimmering heat waves) half an hour after you dialed things down after a reload to smoldering only (no flame), all is working fine - because smoldering only is a rather smoky business. An additional check is to open the bypass in that smoldering only state and see if smoke comes out of your chimney then.
 
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JPS

New Member
Dec 12, 2022
14
RI
Its there a good way to test the accuracy of a cat probe?

The room temperature point on mine is even further off than DWIGHTTBP's. At room temp the needle points to around the N in Blazeking.com, so its between 5 and 6 o'clock on a clock face. Since there are no temp markers, I had assumed it was supposed to sit at 6 o'clock at room temp and it was only a hair out of adjustment. If I leave the air at or near wide open for 30 minutes on a reload, the temp still gets up to around 2 or 3 o'clock (halfway between the 'max' dash and the one before it), and will stay around 2-3 o'clock with the air turned down to a medium setting. If my thermostat is displaying 3 'hours' behind what the temp really is, that means I've had my stove running WAY past the max temp for the majority of the time for 3 cords worth of wood.

If I stick the probe in the oven would that give accurate readings, or would directly heating the coil and display face mess with the reading? What temp should it be reading when it hits the crossover from inactive to active? It almost seems easier to believe that the probe is messed up beyond just the starting point, than that it has been running that hot for that long.
 
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BKVP

Minister of Fire
The red needle should point here at 70F room temperature. You can adjust position by simply slightly loosening nut and turning.

They not highly calibrated instruments. They are however intended to inform users with regard to proper operation of the bypass.

The active line is when cat is between 550-600F. That is when the bypass should be closed.

20230322_064129.jpg
 
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