The Temperature Probes

There are two types of probes that you can use with The Stoker, fire probes and food probes. Click on the thumbnail to the right to see a picture of both types of probes. The fire probe is on the left while the food probe is on the right.

As you can see, the food probe is a pointed straight stainless steel probe, while the fire probe, or pit probe, is a shorter stainless steel probe which is fixed into a clip so you can clip to the grid or to a thermometer stem.

Here is a close up photo of the pit probe. As you can see, the probe fits through a silicone sleve which is held in a hole in the clip. Also notice the heavy teflon-coated wires. They are quite substantial and feel as if they will stand up to the rigors of outdoor cooking.

Here are the secret innards of the plug on each probe. As we stated before, you can plug any probe into any socket. The way that The Stoker tells which probe is which is by storing a unique identifier in this chip which is a part of every probe and blower. When you plug a probe or blower into The Stoker, it reads the chip to determine which probe or blower you just plugged in. Also stored in the chip on each temperature probe is a "calibration factor" which is used to adjust the output of the probe to a real temperature.

Finally, here is a picture of a plug with its cover in place. As you can see, it is pretty well sealed. The cable appears to have more than adequate strain relief, so again, these probes and blowers should be able to stand up to the rigors of the outdoors.

Temperature Probe Accuracy

We mentioned earlier that The Stoker temperature probes are calibrated at the factory and that they contain calibration data on the small chip located in each plug. It is important that the probes be reasonably accurate, both to measure the temperature of the food as well as the cooker. It is also important that multiple probes give similar results so you don't have to worry about which probe you are using, the one that reads 10 degrees high or the one that reads 5 degrees low. We compared the output of seven probes, both at room temperature as well as immersed in boiling water. So, how do The Stoker temperature probes measure up? The following table shows the results that we obtained:

Probe	Room Temperature	Boiling Water
1	76.6	211.2
2	78.4	213.6
3	78.2	213.4
4	73.8	210.0
5	73.6	210.0
6	73.8	210.9
7	75.8	212.4

As you can see, all the probes were within about 4 degrees of each other. According to our calculations, at the time we performed this test, the boiling point of water was approximately 210.7 degrees. All probes were within about 3 degrees, and four of the probes were less than 1 degree off.

The Blower

The Stoker uses a 5 cubic-foot-per-minute blower which attaches to the lower vent of ceramic cookers and in appropriate locations on other cookers. Like the temperature sensors, the blower cable has a plug which contains a small chip. This chip is used to contain a unique identifier so that The Stoker can identify each blower uniquely.

The blowers also contain a unique built-in damper which automatically opens when the blower is on and closes when the blower is off. This serves to stop the natural flow of air through the cooker which could cause the fire to get hotter than desired. The damper works by gravity, so it is important that the blower be installed right side up with the cable on top.