New cat probe

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sprawlnstall

Burning Hunk
Jan 15, 2018
218
Minnesota
After 5 years my original cat probe was faded and nearly impossible to see where the active zone was. I had a fairly good idea but contacted my local dealer and purchased a new one for $48. What a difference in cat take off time. My steel cat was active in half the time it usually takes from a cold start. Does the temp prob wear out? I periodically cleaned my original one. I viewed the new floor models and the new princess and kings have a longer cat probe. The one I purchased is the original.
 
After 5 years my original cat probe was faded and nearly impossible to see where the active zone was. I had a fairly good idea but contacted my local dealer and purchased a new one for $48. What a difference in cat take off time. My steel cat was active in half the time it usually takes from a cold start. Does the temp prob wear out? I periodically cleaned my original one. I viewed the new floor models and the new princess and kings have a longer cat probe. The one I purchased is the original.
I believe that they can wear out and become less responsive but another issue is were you cleaning the probe tip? The coil can also just break but you might not know unless you take it apart.

For others, you can also buy a condar cat meter for the BKs with actual numbers and the active range labeled on the meter. Seem to be every bit as good quality as the OEM BK meter.
 
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Or you can use a Auber AT100/AT200 More expensive, but more precise and reacts faster.
 
For others, you can also buy a condar cat meter for the BKs with actual numbers and the active range labeled on the meter. Seem to be every bit as good quality as the OEM BK meter.
Agreed.
 
Or you can use a Auber AT100/AT200 More expensive, but more precise and reacts faster.
I own one of these and the standard probe wouldn’t work for the bk cat application. Do you own one? Have you ever seen one deployed as you recommend?

They work great in the flue.
 
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Here is my condar after several years of use. My bk meter’s coil broke.

image.jpg
 
I own one of these and the standard probe wouldn’t work for the bk cat application. Do you own one? Have you ever seen one deployed as you recommend?
Interesting. Auber's support people insisted that it would work as a cat probe for a BK King/Princess, so I ordered one for that purpose. Haven't tried it yet. I'll have to get in touch with them again and double check. Thanks for the heads up.
 
They sell other probe styles and if they make one just right for the BK that would be interesting. Note that you need the probe tip to be “dangled” in exactly the right spot. So vertical length must be the same as the oem meter.

It’s not enough to just fit in the hole sorta.
 
I did ask specifically about the probe length, but I haven't opened the box yet, so I'm not certain which probe they sent.
 
Called them again. This time the tech support people were relatively clueless. Looks like the 'TC-K-BR' (https://www.auberins.com/index.php?main_page=product_info&cPath=20_3&products_id=291) probe sort of works (4" probe tip, max 1800 deg F), but it isn't immediately obvious that it can be mounted in a way that would hold it in place. A few fender washers might be enough.

Hmmm...the page for the AT200CHIM (https://www.auberins.com/index.php?main_page=product_info&cPath=17&products_id=292) suggests that probe for use with double wall pipe, but shows a max temp of 1650 deg F. The spec inconsistency does not inspire confidence.
 
You’d need some sort of collar with a set screw so you can set the depth of the probe. More so than with the BK style conductive probe, the thermocouple reads at a single point at the tip which needs to be centered and within a certain distance from the back of catalyst.

Then you’ll have the restof the probe, plus a big wire, sticking up out of the stove top. It’ll look “scientific” along with the glowing digital readout hanging on the wall with more wires to the power supply.

Might as well get three. Flue temp, cat temp, and surface temp. 😆

I like the high quality condar meters but it would be nice to be able to read them from the couch.
 
You’d need some sort of collar with a set screw so you can set the depth of the probe. More so than with the BK style conductive probe, the thermocouple reads at a single point at the tip which needs to be centered and within a certain distance from the back of catalyst.

Then you’ll have the restof the probe, plus a big wire, sticking up out of the stove top. It’ll look “scientific” along with the glowing digital readout hanging on the wall with more wires to the power supply.

Might as well get three. Flue temp, cat temp, and surface temp. 😆
First time I spoke with Auber the stove was cold. Took the BK cat gauge out and measured its length: 4 inches from the top of the stove to the tip of the probe. As far as I can tell, the BK probe and the Auber probe are very similar size and shape below the surface of the stove. I can check that again more carefully the next time the stove is cold (next April given the current long range weather reports
:)
).

The scientific look would be an issue for some, but I've got enough improvised equipment around here that one more piece would fit in with the decor.

I've already got a stove surface gauge (a Condar). It's mostly there as a "this surface is VERY HOT" warning for visitors who might be tempted to touch it to check.

The BK conductive probe v. the Auber point reading might be the key difference. If the cat temp was consistent enough at different parts of the 4", it would probably be possible to find a representative place to put it. I suspect that the temps are not that consistent. The BK/Condar conductive probe samples over a longer length, so the inconsistently doesn't matter as much.

Interesting: the Condar website mentions a 1 7/8" probe (the 3CX-2) for "some [unspecified] Blaze King models", but they appear to be measuring from the inside of the stove surface, not the outside. Not entirely clear which Condar model would work with a 2023 PE32.

I don't really need the accuracy of the Auber, but I'd like the quicker response time. Hysteresis has value, but cat probes are slower than I'm really comfortable with. Maybe I'm just too used to lab equipment.
I like the high quality condar meters but it would be nice to be able to read them from the couch.
Point an rPi camera at it, export it to your hearth.com icon, and read it from New Zealand (or your couch). :)
 
You’d need some sort of collar with a set screw so you can set the depth of the probe. More so than with the BK style conductive probe, the thermocouple reads at a single point at the tip which needs to be centered and within a certain distance from the back of catalyst.
Opened the Auber box. One issue addressed. The BK OEM cat probe and the Auber TC-K-BR probe are the same length below the surface of the stove. The Auber probe has a max temp of either 1650 deg F or 1800 deg F (the spec page is confused). 1800 should be high enough. 1650...maybe.

The 4" length does not appear to match the specs for the Condar 3CX-2 ("for some Blaze King models"), but it does match their 3-12-1 ("generic & Vermont Castings...").

IMG_20231103_145128_1024.jpg
 
Opened the Auber box. One issue addressed. The BK OEM cat probe and the Auber TC-K-BR probe are the same length below the surface of the stove. The Auber probe has a max temp of either 1650 deg F or 1800 deg F (the spec page is confused). 1800 should be high enough. 1650...maybe.

The 4" length does not appear to match the specs for the Condar 3CX-2 ("for some Blaze King models"), but it does match their 3-12-1 ("generic & Vermont Castings...").

View attachment 317994
That’s just the standard probe they send for all including what I got for a flue probe application. How do you plan to hold it down tight to keep that probe vertical?
 
That’s just the standard probe they send for all including what I got for a flue probe application. How do you plan to hold it down tight to keep that probe vertical?
Auber's site claims it is a 4" probe. BK does not list a probe length, but I had already measured it at 4". Now I know that the real (instead of claimed) measurements from the top to the stove to the tip of the probes is the same. There's enough ambiguity in the BK and Auber info that the confirmation is helpful.

The BK probe is held in place by its own weight. That won't work for the Auber probe. A screw hole could be drilled and tapped in the top of the stove, but I don't want to do that. If the probe wire can be fixed in place so that it can't put much force on the probe (looks doable), then a stack of fender washers could hold the probe down as least as well as the BK probe is held down.

So...the remaining issues are preventing the probe wire from being moved and thus moving the probe; whether or not the Auber probe can handle sufficient temperature; and whether or not the combustion dynamics require analog sampling along the length of the BK (or Condar) probe or if sampling at the probe tip is sufficient.

The highest marked reading on the Condar analog cat probe is 1600 deg F, so the Auber TC-K-BR looks marginal if it is rated for 1650 deg F; somewhat better if it can handle 1800 deg F. 1650 deg F is probably good enough as long as it does not damage the probe, but the effects of higher than rated temps are not mentioned on the Auber site.

The existence of the Condar Watchman suggests that Condar, at least, believes that sampling at the probe tip is sufficient. But the Watchman manual glosses over holding that probe in place. It also says that installing a 9v battery AND connecting the wall wart supply will destroy the Watchman control board. It's easy and normal to avoid that kind of problem, suggesting that the Watchman design can't be trusted.
 
If you toast the auber probe, I believe the probe part is not terribly expensive to replace.
 
You're right: $18. Not worried about that. I suspect that tip sampling is good enough, although I don't know of a way to prove it without some third, known reliable (enough) way to measure the cat temp. I'll probably end up buying a Condar analog meter as the best available cross check. A '3-12-1' looks like the best match, although the description mentions 'generic' and Vermont Castings, not BK.

I'll do the experiments when I have the Condar probe and some time.
 
So, I ordered a Condar 4" cat probe from Amazon (nice birthday gift for myself; the thermocouple I've been using has to be rewelded.often, and it was a pain to seal the hole and get the glass fiber sleeving through).

The box says it's a 4" probe, but the probe is 2-1/4" (2-3/4" with the gauge at the top).

Back it goes.

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