I have an OBS with an Auber dual PID. I haven't been real good at keeping logs on my smokes (6 or 7 total), but it dawned on me this weekend that I may have a glitch in the system.
I did two smokes this weekend, my first shot at B-backs and my 3rd set of chickens. In both cases, I let the pid control the cabinet heat and have no problem preheating to 250. In the case of the ribs, 3 racks, I backed the cab heat down to 225, filled the large pan with boiling water and went at it. I didn't IT the b-backs, but pulled them after 5 hours and they were well done and nice and moist. I noticed that the cab temperature never did get up to the 225 goal, maybe 208 at the end, but the ribs were fine and I don't think the time was out of line.
In retrospect, I thought that with the small amount of mass and meat in the ribs, the cab heat should recover without a problem. I didn't open the door until the 5 hour mark, the ambient temp her in S. Cal. was in the high sixties and the OBS is in a cabinet so wind is not a consideration.
Yesterday, I set the pid to 250, vent full open and pan full of boiling water and loaded 10.5 lbs of chicken pieces on three racks. I stuck the second probe in a breast and watched for an IT of 165. Between 6.5 and 7 hours later, we were done, but the cab temp never got above 180 according to the pid and it came pretty close to being the same on the door thermometer.
I'm a little befuddled and am thinking of trying a little experiment this next weekend. I will do two smokes of the same meat and weight, probably chiccken again. On the first smoke I will let the pid control the cab temp and I'll more consistantly monitor the temps. There should be no reason to open the door.
On the next smoke, I will disconnect the pid from the system, but leave the probes in place to monitor the temps. I guess what I am looking for is the possibility that the pid is hold back on letting the cab temp come up in temperature.
If this makes sense to anyone, or if you have any thoughts, I'd appreciate the hearing from you.
Thanks, Randy
Where is your PID cabinet probe located?
I usually have it below the lowest rack, near the front.
Quote from: SoCalBuilder on November 08, 2010, 10:15:44 AM
Yesterday, I set the pid to 250, vent full open and pan full of boiling water and loaded 10.5 lbs of chicken pieces on three racks. I stuck the second probe in a breast and watched for an IT of 165. Between 6.5 and 7 hours later, we were done, but the cab temp never got above 180 according to the pid and it came pretty close to being the same on the door thermometer.
What I would do is watch the green "out" light on the PID. When it is on it means that power is going to the cabinet. So if you never hit above 180, then the PID green light should have been on all the time. It may blink off and on, but it shouldn't be off for more than a second or so. Normally it stays on until the temp gets close to the set temp and then it will go off and on as it attempts to "coast" to the desired temp. (That what autotune does, it finds the settings for "coasting" to the desired temp.)
So if the temp is never at what you set and the green light is basically on all the time the PID is doing its job.
As far as getting to temp at 250, the boiling water is about 212* so it will absorb some of the heat, the chicken moisture will also absorb some.
So see what the green light is doing.
Agree with Gus. That will tell you if the PID is trying to deliver the power to the heating element. If it is and the temp is low, crack the door and sneak a peak at the element. Is it glowing as it should be ?
another item to check is the slider control is 90 % to the right? if not you will have a low temperature as well