Post your live HeaterMeter Cooks


 
Im jealous of everyone's thermoworks probes that actually work. Mine just freak out and don't hold a stable temp.
 
PaulFisher said:
Im jealous of everyone's thermoworks probes that actually work. Mine just freak out and don't hold a stable temp.
Click to expand...

Mine work fine too... Try grounding the braid of the lead wire to something on the Heater Meter to see if that reels them in....(the metal on the rPi LAN shell will work for testing purpose)...
 
Starting a long overnight smoke at http://bbq.converged.ca

FICinMDl.png


2 8lb shoulders.

s3epueNl.jpg


My $0 HeaterMeter and servo damper protection system

IPyCUSTl.jpg
 
Last edited:
2 racks of ribs on the egg. I ran out of wood chunks so I put in a couple of handfuls of cherry pellets. I'm not sure it was a good idea because they appear to have filled many of the spaces inbetween the lump where air would flow through. I guess time will tell...

http://heatermeter.kolenet.com
 
Things sort of went off the rails around 6:45 this morning. It looks like the blowing fan started to extinguish the coals rather than stoke them. The cooker was cleaned out and charcoal was placed in by hand to ensure proper air flow for the grates, so I'm not sure what happened. I think I may need to extend the tub that blows air so that it's sticking further into the kamado. Right now nothing extends beyond the face of the mount.

I managed to somewhat get things back in line my manually modulating the fan by toggling fan max between 0 and 50.

I think the heatermeter could benefit from this type of functionality. ie: if the fan is is set to 100% and the temps keeps dropping, adjust the fan routine so that it only comes on for 10 seconds of each minute and see if the temps start rising.

I've also got the fan adjusted for 5% min, 10% max. It was set to 10% min, 30% max.

leUhwWql.png
 
To clarify, when did you take action? Is it around 7am when the temperature goes up? Did you open the lid at this point to do anything?

I see the temperature dropped around 6:30am to the point it eventually kicked in the lid detect (the third time in the group of lid detects). The blower was off for (if using the default values) 4 minutes there, at which point the temperature continued to drop. When the fan turned back on the temperature didn't go up at all. I don't see how your recommended feature of turning off for a little then turning back on will solve anything because that's basically what happened (although the duration are a bit different).

If I see things like this on my system it is either an out of fuel situation or pretty close to it and the ash is finishing the job of putting the fire out. In that situation, if I remove the HeaterMeter and open all the vents the fire just goes out anyway so in my mind there's nothing I can do to save it. I'd be interested in finding a method to extend the burn, although HeaterMeter doesn't really have much concept of time. It can't really tell it is in that situation beyond the fact that the output has been 100% for "a while" and the only knows temperature over the last 30 seconds.
 
Steve are you running the stock grate? I don't understand why the BGE doesn't come with something like the High-Que. The stock grate has a bad habit of getting clogged with ash. Maybe that's what happened? I used to have to use a "wiggle stick" to clear the ash before upgrading the grate and using the HM. Now no worries about ash clogs.
 
I took action at around 7am by opening the lid, removing the main cooking grate and the heat deflector to inspect my fuel situation. I had tonnes of coal left and the fresh air looks to have lit it up because thats when the super spike happened. I didn't stir the coals because it didn't look like much had been burned off at that time.

Once the spike settled down and the temps dove again, I started manually modulating the fan and got things under control by about 9:30am. I still had to modulate the fan till about 11:45 and then things settled in on their own. I just added a tray of beans and mixed up the coals while doing so and it's been holding at 220 like a champ.

4KMD3VEl.png


Also, this is a Kamado Joe, not a BGE. The KJ fire grate looks like this, although in this picture, it's actually upside down. Also, see the gap between the fire box and the outside wall? Due to the way my fan is mounted, It looks like I'm blowing the air up between the outer and inner walls. If I had an extension tube, I could get the air to blow right under the fire grate.

4ZKZKkBl.jpg
 
Last edited:
Oops sorry, I should have noticed the Kamodo Joe.

Here's my stock BGE grate next to the High-Que. The consistency and volume of airflow is way better with the upgrade.

FF884872-C542-41D1-ABC5-8BAA416AA86F-4599-000002967E27E10F_zps25962dbe.jpg
 
Steve, I've experienced the same thing as Darren with the BGE and upgraded to the same grate. With that stock pattern, you are almost guaranteed to clog the holes after several hours of cooking. Upgrading the grate makes a huge difference.
 
Thrill to development as I do a test of a Thermocouple Pit Probe with live noise readings on the Big Green Egg with a Rotodamper! Probe 1 is stuck in the top vent of the egg, the pit probe is a bare thermocouple poked in at grill level near the edge.

http://home.capnbry.net:22675/luci
 
It worked acceptably through the night, but there's still at least 2 LSB of noise even with sampling around the blower "turn on" time. I am going to do some surgery on the PCB tonight to see if I can better isolate it.

I also find that the bare thermocouple is a little too sensitive because the the temperature appears to drift a fraction of a degree. It seems you need some sort of small amount thermal mass to even them out. I'm not positive about that just yet, because it might be a function of noise.
 
juangarcia said:
tom,
what pid settings are you using?
Click to expand...

b:0
p:3
i:0.01
d:5

edit: I just upped the derivative control to 7 to see if I can improve the over/undershoot.

edit2: I liked how it was going so I got greedy and upped D to 10. It backfired. I'm back down to 6.
 
Last edited:
You must log in or register to reply here.

 

Back
Top