Digital Probe Thermometer for catalytic stove

I am interested in adding a digital probe thermometer to my Woodstock Keystone, and am curious if anyone has used one before? My Keystone has a place for one at the rear of the stove, but I can't figure out what would hold the probe in the proper place relative to the combustor? That is, it seems like the probe would just fall down, unless it fit really snug in the hole?

Also, any reasonably priced digital thermometers out there that do more than the Condar? It would be nice if there was one with an alarm feature.

What holds the probe at a right angle to the access hole? Does it just fit real snug in the hole or something?

So I take it you have to press a button on the controller for it to turn on, and then it shuts off after 10 minutes?

bmwbj said:

rmc, I use a digital probe in my VC Intrepid II cat stove, and this is the only way
for me to insure proper cat operations. The probe slides into an access hole slightly
above the cat in the rear of the stove. I think it works well, but the "Condor" unit I have
only stays turned on foe about 10 min. than shuts off to save battery life.
When my cat is up and running correctly, the temp probe reads about 1400 degrees and can fluctuate
between 1200 and 1800 depending on what type of wood and burn cycles.

Click to expand...

What keeps the end of the probe in the right place relative to the combustor? On probe themometers with the standard dial, there is a magnet that keeps the probe in a straight line. What keeps the probe in a straight line with the digital one?

bmwbj said:

You are correct about tapping the button on, and yes it only stays on for about
10 min. Than if you wish to see the temp again you have to hit the button again.

In the back of you stove there will be a small Chrome looking "button" plug in the access hole for
the probe to go into....I simply removed that "button" and pushed the probe in. I did this with the stove
opened up and the cat removed so I could see where it came out on the inside, and how deep to install it.

It is a very simple install. It pushed right throught the refractory material and sits just above the cat.

Click to expand...

Thanks, Todd. Good to know. I ran a search as well, but couldn't find anything either. Another thought I had was to use a standard probe thermometer that inserts through the top of the stove. On my Keystone, that will require drilling a small hole through the removable top-plate, which will allow the end of the probe to sit in the right spot. Not a big deal as far as the install. I'm not sure what the lid of the Fireview is like, but going through the top might work as well...

Todd said:

I tried the one from Condar and it was too large for the hole so I bored it out for a snug fit. You also need to tell them how long you need the probe, I think I ordered an 8" and they sent a 6" and then I could never get it to work so I sent it back and filled the hole with furnace cement.

There are better alternatives out there. Someone posted some here a couple months ago they found on E-Bay, but I can't remember the thread and can't find it using the search.

Click to expand...

I am ordering my cat probe thermometer first thing monday, so I'll let you know how it goes. I'll let you know my exact measurements once I do it. The trick will be getting the end of the probe approximately half way between the heat shield and the combuster itself (vertical measurement), while at the same time being within 1" away (horizontally). A probe length of roughly 4 5/8" looks to be about right. This is on the Keystone. I'm not sure about the Fireview.

I've talked to Woodstock and they didn't mention anything about the thickness of the soapstone being a problem. What they said is important is that the END of the probe must be approximately one inch from the catalyst. That is, approximately one inch from the catalyst itself, and not the cast iron iron housing that holds the catalyst. Since the probe will be inserted from the top down, this means that there is a very specific length that the probe must be in order to sit just between the cast-iron housing of the catalyst and the heat shield, which is an approximate 1" gap vertically. So the measurement top down must be precise, as well the measurement from front to back.

Todd said:

I just wonder how the thickness of the soapstone will effect the probe readings? Might be a smart move to ask Woodstock about this before drilling any holes.

Click to expand...

Nope, not at all. I won't know the size of the bit until I get the probe, but I will just use a standard metal bit.

Todd said:

So they didn't try talking you out of it? What kind of drill bit are you going to use?

Click to expand...

I installed my new catalytic probe thermometer on my Keystone this past weekend, and I wish I had done this a lot sooner. I am engaging the cat far earlier than I ever did with the stove top thermometer, due to the time it takes for the stone to provide a sufficient temp reading. However, regardless of what the cat probe says, I still wait about 10 minutes for any excess moisture to burn off. I imagine less wood will be wasted now, since I won't be waiting so long for the stove top thermometer to read the right temp anymore. Burn times are great...today I was gone for almost 11 hours and when I got home the stove top temp was about 200 degrees. After reload, the wood had flames within about 30 seconds, then approx 10 minutes later the cat was ready to be engaged.

After 11 hours my stove top temp was just over 200. I can't remember what the probe temp was, but I imagine it was pretty low. I'll pay more attention to this over the weekend. Just now I refilled the stove and walked a way for several minutes...came back and the stove top temp was just a hair over 250, and the probe reading was about 650. I engaged the cat, and now just moments later the probe is reading a bit over 800 and is continuing to steadily rise.

Installing the probe requires some measurements to determine where to put the hole for the probe, but you can figure it out pretty easily just by measuring the distance of the cat from a specified point on the stove, and then transferring this measurement to the stove top. As far as the length of the probe...that's not an issue as the probes can be cut to the desired length. I ordered the longest one and just cut it to the length I needed. Mine has the smaller dial (1.5") and I drilled a 3/16" hole for a perfect fit. The probe came with an eyelet, which you don't need if you are drilling your own hole. The eyelet fits in a 1/4" hole. Again, the probe isn't hard to install. Just measure twice and drill once. Worst case scenario is the hole is in the wrong spot and you have to plug the hole or get a new soapstone top. With some careful measuring, however, this really isn't a concern. Just checked my stove....stove top = 400, probe = 1100.

Todd said:

Good to hear it worked out. I'm still chicken doing it to my Fireview, I'm afraid I won't get the measurement right and it's hard to judge how long I need the probe. So when you say 200 degree stove top is that your new probe temp after 11 hours? How does the probe relate to external stove top temps? What's your probe say when external reads 250?

Click to expand...

I believe the probes sold by Woodstock are by Condar, which is what I have. I think you will be happy you are ordering one. What stove are you getting?

akennyd said:

rmcfall, I've wondered the same thing about having a lag in the reading on the stove top reading. Thanks for the info on your experiences.

I emailed Woodstock about the cat probe/thermo and the reply was that it was still available and that it is $26. I'm going to order one but I'm waiting to get one when I order the chimney parts that I know I'm going to need...

Kenny{

John 3:16

Click to expand...

For my reload this morning, which was about 10 hours from the previous load, the stove top temp was just below 250 and probe temp at 500. Upon reload, I opened the air up for a good amount of flame. Five minutes later the stove top temp is a fraction higher, but still below 250. Probe temp at 600. I went ahead and engaged the cat (I have been waiting about 10 minutes even with an adequate probe reading, but thought I'd see what happens when engaging sooner...), and now five minutes later the stove top temp is still below 250 and the probe temp is just above 700. Cat is glowing a little, but not a real strong glow.

Five more minutes stove top is just below 300 and probe is just below 900. Cat still just glowing a little. Had the cat not been engaged, I bet stove top would barely be 250 right now.

Five more minutes and the stove top temp is about 325 and probe just above 900. Cat glowing strong in one spot, but not a solid glow across the whole thing.

Five more minutes the stove top is just above 350 and probe at 900 (dropped a fraction), and the cat glow hasn't changed much.

Five more and the stop top is 375 and the probe is a fraction above 1000. Cat is glowing strong on the ends, but not in the middle.

Five more minutes (30 minutes since cat was engaged) and stove top at 400 and probe 1100. Cat not glowing as much...just glowing on one end.

Worth noting is that my stove top thermometer is placed as close to directly above the cat as I can get it. If it were moved just a few inches, the stove top temp readings would be much less.

During the current instance, I had a little more flame than I usually allow. It was a slow flame, but just a touch more than I prefer. I left the air setting alone (at 1), however, to keep things constant throughout the readings. I have found that if I reduce the air and consequently the flame, the cat will usually glow more strongly. What does this glow really indicate? Anyone know? In the past, I would use the cat glow as a gauge, although this probably isn’t very reliable. In the current instance, if I had NOT had the probe thermometer, I would NOT have left the cat engaged because it did not have a strong glow initially. Consequently, I would have burned up a lot more wood in the meantime. However, with the probe thermometer, I could see that the internal temps were steadily rising, which I understand indicates the cat is working.

A concern of mine with the probe is that the initial probe reading could read hot enough (500) for the cat to be engaged, but that a lot of moisture could remain that could damage the cat. In the current instance I engaged after only 5 minutes, so could there still be too much moisture in the stove even though the probe reading was 600 when the cat was engaged? I usually wait longer to engage the cat, but thought I’d see what would happen in this case....and it turned out the cat temps steadily increased so maybe it is fine?