Vermont Casting Intrepid Flexburn catalytic probe installation concern

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VermontCrapstings

New Member
Feb 16, 2024
49
Tennessee
My concern is that after installing the probe as the manual says, via twisting and pushing through the fiber panel, I have created too large a hole. It is large enough to see light around the probe itself.

For the sake of information about the probe in question. It is an Auber instruments K type high heat probe 6in length. The length is also a little long for the depth required for this stove. At full insertion it goes past the catalyst.

I have attached the version of the manual I am using for reference. My initial thought is that it is likely ok due to the fact of it being downstream of the combustor, so to speak. However, it is still within the secondary combustion chamber so I would rather ask for a second opinion. After lurking these forums for some time I feel some of you may be of more help than VC or my not so local stove dealer/installer.
 

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I used a small drill bit to make the hole first then pushed the probe in. Mine sticks out quite a way, I had the cat out and set it to the middle of the stream. I marked the probe so I knew the right depth I wanted. I did get around to making a support bracket that clamps to the probe to hold it in place.
 
So a little gap around the probe is not terrible. As the fiberboard wares out you will see this anyway.. Alot of board missing is an issue as the fiberboard is the Shield protecting the back of the stove
So at what point does it become an issue? What about extra oxygen getting into the secondary?

I would like to add the size of the hole is about the size of the hole in the sheet metal provided for the insertion of the probe itself.
 
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So at what point does it become an issue? What about extra oxygen getting into the secondary?

I would like to add the size of the hole is about the size of the hole in the sheet metal provided for the insertion of the probe itself.

So your not adding air or oxygen into the secondary.. your adding air or oxygen to the gasses going up the flue.. secondary air combustion is actually only happening in the secondary chamber.. the prob is located in the exhaust portion or backside if the catalyst. The probe is measuring the combustion that already happened.. your not adding anything its not making a difference. The only thing the fiberboard is doing is protecting the cast from the extreme heat the catalyst is putting out. So not large gouges or pieces missing is the goal.. 1 small hole .. is not doing much.. Its ok..
 
So your not adding air or oxygen into the secondary.. your adding air or oxygen to the gasses going up the flue.. secondary air combustion is actually only happening in the secondary chamber.. the prob is located in the exhaust portion or backside if the catalyst. The probe is measuring the combustion that already happened.. your not adding anything its not making a difference. The only thing the fiberboard is doing is protecting the cast from the extreme heat the catalyst is putting out. So not large gouges or pieces missing is the goal.. 1 small hole .. is not doing much.. Its ok..
Ok, thank you for the response. I'll just keep an eye on it and make sure it doesn't get any larger.

Any recommendations on a bracket for the probe? The one that comes with the performance pack from VC is not available for individual sale.
 
I used a piece of plumbing strap and formed it to fit. My stove has the catalyst access on the back with screws holding it so I anchored it there. You just have to get creative.
 
Ok, thank you for the response. I'll just keep an eye on it and make sure it doesn't get any larger.

Any recommendations on a bracket for the probe? The one that comes with the performance pack from VC is not available for individual sale.

me personally Id get a small piece of sheet metal cut it bend it drill and screw it to the heat shield
 
My stove came with the factory installed probe so I took that bracket and adjusted the angles on a couple of the bends to make it a bit longer. Then drilled the holes just a bit bigger for the Auber probe to slide through which gave it decent rigidity. Angled the bracket a bit with the screw holding it in place and it works well so far.

For what’s it worth when I pulled it apart to install the probe I found they had popped a decent chunk (1/4” or so) of fiberboard out when they put the factory one in. Didn’t appear they used a drill bit. Did what I could to wedge it back in around the new gauge and not too worried since it’s not adding air to the fire as Woodsplitter explained.
 
I just installed my new Encore today and the part you show is exactly what came with my Encore and it worked great to hold my cat thermometer in place matching all the predrilled holes.