Placement of firepot monitor.

[caustin12]

Since this temp probe is from a max6675, I assume it is a K-type thermocouple. I have a pitboss smoker. Where would the ideal placement of this monitor probe?

[jazzmonger]

Good question. I thought I had posted pics of what I did but I guess not. I have a Traeger, but I'm sure most fireboxes are similar.

I've tried 2 different sensors. One is a screw on and I welded it on the fire pot like this:

it worked ok, but not great. The flange moves the sensor away from the firepot and prevents good heat transfer. The other one I tried was this one:

The benefits are many. I drilled a hole, and ultimately riveted it on (after trying it w/ a screw to hold it on) with a stainless steel rivet in about the same location. It sits right up against the firepot, it was much more responsive and a lot easier to mount. My relighting routine works perfectly and has already saved me from a massive pellet mess a couple of times.

Here's a good example of exactly that during an 8 hour cook I was in the middle of when the fire randomly went out for no apparent reason:

It recognizes the fire is going out, turns on the hot rod and relights the pot, saving a pellet mess and, more important, saving the entire cook. Pretty spiffy if I do say so myself! Now, if you run out of pellets during a cook, that's on YOU! I suppose I could add a fire_went_out sensor flag and trigger an automation to send an alert that the fire went out while the unit was on and in operation. Hmmmmm....

[caustin12]

thanks again! Would a 400C max temp thermocouple be suitable for this application? From your chart above, looks like ~650F was the peak.

[jazzmonger]

Probably be just fine. The important temp is when the fire goes out, which is MUCH lower than 400C.