Condar cat thermometer sucks

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Minister of Fire
Hearth Supporter
Jan 6, 2009
I seem to repeatedly have this problem with Condar combustor thermometers (the kind with a 1-2" metal probe that sticks down near the catalytic converter). Several times I've had the "zero" get off, where when the stove is cold, it reads WAY below the room-temperature level; recently, I have one that reads several hundred degrees when the stove is cold (and over 2000 degrees when running).

I've taken these apart several times and still can't figure out how they're supposed to work. The basic problem is that the inner end of the coil spring slips, that is, it doesn't stay firmly fixed into any one spot. I'm not sure how it's supposed to do so. It looks like maybe a little hook bent into the end of the spring is supposed to catch against a high point on one of the hex nuts that hold the thing together. But I can't get it to stay. I'm at wits' end.

What am I missing ? Am I the only one that has this problem ? Is there a better thermometer available ? Searching, I've found some mention of using an infrared one, the pistol type I assume, but I'm not sure where you'd aim it.
This looks like it might work. No mention of wood-burning usage in questions or reviews though. Confusing that two maximum temps seems to be quoted, 1562 degrees-F for thermocouple, 2372 for pyrometer.

I can't get the Amazon link to work though. Searching (in Amazon) "k2 High Temperature Digital Pyrometer" and looking at the third item down, seems to work.
Called 'em, they say no longer under warranty. Say if it gets too hot, there's a weld that breaks (I guess what keeps the. inner end of the spring in a fixed position) ?

Can someone remind me what specific model (probe length) is required for BK Princess ?
Depends on the year the stove was made. Mine uses the 3-12-1. AFAIK some of the earlier stoves use the 3CX-2.
My condar cat meter has been great for several years and a definite upgrade from the BK oem meter. Holds zero perfectly with no adjustment needed season after season. Just like the flue meter from condar.

What’s going to kill both of these is the corrosion of the actual probes. Over time the corrosive gasses erode the thickness.

Maybe don’t mess with the calibration on the next one. Did it really need adjustment fresh out of the box?
I just got a 3-12-1 for my Princess a couple weeks ago. It works great. I agree it’s an upgrade over the stock gauge. The highest temp mine has been up to so far is 1400.

It looks like the gauge goes to 1700. And that’s outside the “recommended” zone. I wonder what temp the weld breaks at.
Maybe don’t mess with the calibration on the next one. Did it really need adjustment fresh out of the box?
No, not fresh out of the box. At some point I noticed the zero (when stove cold) was WAY off, and that's when I realized the inner end of the spring was not attached to anything. So I bent a little hook in it and got it to catch on one of the hex nuts there.

Maybe my cat just gets too hot.
One thing I just noticed with mine is the face is already starting to discolor. It must have a sticker instead of painted like the BK gauge.

The BK gauge still looks new.

Condar cat thermometer sucks
I still think something like this could work:

I don't understand wny Amazon links won't work. Search "Full Range High Temperature K-Type Thermocouple Sensor Ceramic Kiln Furnace 2498F 1370C CR-14" at Amazon.

Could you lengthen the wire to get the meter a safe distance from the stove ?

Would the probe fit into the hole on top of the stove, and the correct distance ?

They also sell a bunch of thermocouple probes, that look like they'd fit in the stovetop hole, could be adjusted to the correction insertion. depth, and have a 2 meter long insulated wire. Looks like we want a Type K thermcouple, and then just connect the wires from the thing to a voltmeter, using this table:

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