Digital Cat Thermometer

First off I would like to say "hello" to everyone on the forums. I have been doing a TON of reading on here about what stoves people like, and how to properly run a cat stove. Love the forum! This will be my first post.

When I was growing my family had an old non EPA insert that we used for our primary heat during the winter. I always loved that thing as a kid, to me heating with wood just has so much more character to it than setting a thermostat on a gas furnace. I finally had an opportunity to purchase my first wood stove for my own house. I decided on going with a Blaze King Princess insert. I have it heating a 1,500sf single story with full finished basement. Its on the first floor of the house so I don't know how well it will do getting heat down stairs this winter, but we will find out! I have a direct vent gas log fireplace down stairs I can use for supplemental heat during the night when I'm home if I need it. I put it in about two weeks ago with a insulated SS liner and all I can say is wow! So far it hasn't been under about 40, but I'm looking forward to the temps heading towards zero this winter so I can let this thing stretch its legs a little.

With enough searching on the forum I have been able to pretty much answer every question I had in regards to proper running, but the one thing I didn't see very much was digital cat thermometers. I wasn't very pleased by the thermometer that came with the stove. It was the usual BK "inactive" "active" thermometer that doesn't even hint about actual temperatures. I went and did some looking to find a much more accurate digital thermometer, but there are not many out there. Almost all of the ones I found were battery powered, and would automatically shut themselves off after a while to conserve battery power. I was looking for something I could see from across the room, without having to walk over and push a button to turn it on. What I ended up going with was a thermocouple setup that's designed for pottery kilns. Its AC powered, and does not automatically shut off. As long as its plugged in, it shows the temp. I did have to change out the actual thermocouple that came with it, the kiln style one just wouldn't have properly fit the stove, and I didn't want to actually cut metal and either ugly up the stove, or void warranties. Ebay has a TON of various K style thermocouples in pretty much every shape and size you can imagine so I found one that has the same length probe as the stock BK thermometer, and was rated for 2,000F and it fits right in. Now I have a to-the-degree measurement of cat temps. It also has a high temp alarm that can be set so if the cat gets too hot, the thing will start beeping like crazy. I like that the stove will now yell at me if I let it get to warm.

That brings me to the actual question, since its still fall and I am having to keep the stove set just about as low as it will go, whats the lowest I can safely run it without risk of crudding up the cat? I know light off temp is around 500, but after its going what do you guys normally consider the 'lowest' it should be kept idling at?

If anyone is interested in the thermometer its a Auber AT100

Thanks,
Patrick

As far as I can tell the temps are dead on. I don't have any good reference since the stock thermometer doesn't have any numbers on it. I did test the thermocouple before putting it in using ice water (32F reference) and boiling water (212F reference) and it was dead on for both those. The hole for the thermometer on mine is about an inch downstream of the cat, so its between the catalyst and the flue. I'm not quite sure, but the stove has a piece of angle iron welded to act as a shield between the cat and the probe tip. I'm guessing probably to make sure its reading actual exhaust gas temp and not being affected by infrared radiation from the back face of the cat. Mine normally shows 500-1,250F. The cat starts to have a faint glow around 1,000, and its a nice orange by ~1,200. I did take an IR thermometer to the top of the stove, and it reads right about half what the thermocouple reads so that leads me to believe that its pretty accurate. Most places I have seen say stove top temps are normally around half the cat temp.

If your not wanting to punch more holes in your stove to move it behind the cat, what about running the wire down between where the flue connects to the back of the stove and putting the probe right behind the cat that way? Maybe make a little metal bracket to hold the tip of it up in the air so its not resting on the floor of the smoke channel. Not sure how your stove is constructed on the inside so I don't know if there will be bypass doors in the way or not. Just an idea. Any gap the wire leaves in the flue, just fill with furnace cement.

Is the wire on yours insulated with some kind of rubber? The wire that came on mine is insulated with fiberglass between the two conductors, and then a braided SS cover over the entire thing. I got it for 15 bucks or so on ebay, you could always grab a cheap one and give it a shot. Maybe it will hold up better than you think, worst case your out 15 bucks and a bit of time putting it in.

Got and IR thermometer for that! I guess I could get more thermocouples and just stick them all over the thing, but then it might start looking too much like frankenstove. One for flue temp might not be a bad idea though since its a insert and you can't see the flue with the surround on it.