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6. Important consideration for better control results.
The following is a list of things that could affect the result of temperature control.
a) The smoker and controller location. The smoker should not be placed directly in the
sun. Direct sun light can heat the smoker to above 140 °F in the summer time, making
controlling the temperature at 140 °F impossible. This is especially the problem for the
black color smoker. The controller should be placed away from direct sun light also.
Although the controller uses a high intensity LED display, it will still be difficult to read
when sun light is directly shined to its surface. Users should also avoid exposing the
controller to water and rain, which could damage the controller.
b) Low temperature control. The control result for temperatures below 125 °F will not be
as accurate as for higher temperatures when the smoker generator is on. This is
because there are two heaters in the smoker tower. One is the smoker heater controlled
by the PID controller. The other is the heater from the generator that is not controlled.
Our test shows that the heater in the generator itself can raise the temperature of the
smoker tower by 60 °F (2 hours, in the shade with damper open). That means when the
ambient temperature is at 70 °F, the smoker can be heat up to 130 °F in 2 hours by the
heater of the generator (without using the heater in the smoker).
c) Damper position. Keeping the damper open will result in better temperature stability
because more heat loss is created. This is important when the temperature is set below
140 °F. When the damper is closed, the temperature will take longer time to drop if it is
overshot during initial heat up. At higher temperature, closing the damper will not affect
the performance much because the heat loss from the wall of the tower is increased.
Close the damper at high temperature will keep the moisture of the food.
d) Temperature uniformity of the smoker tower. Our test shows that when the all the
shelves were empty, the temperature inside the smoker tower is fairly uniform except the
back half of the lowest shelf that is close to the heater. User should avoid placing the
sensor too close to the heater because it does not represent the temperature of the rest
area. When the shelves are filled, temperature variation might depend on how the foods
were placed. The bottom shelf can become hotter if more food is placed in it to block the
hot air from going up.
e) Operating the controller when ambient temperature is below 32 °F (0 °C). The
controller reading is only accurate for temperature ≥ 32 °F (0 °C). In addition, if the
ambient temperature is below 14 °F (-10 °C), the controller will not function because it
can’t read the temperature correctly. In that case, user can warm the sensor by holding it
with their hands. Once the sensor is above 14 °F (-10 °C), it will turn on the heater. Once
the inside of the smoker is heated to above 32 °F, the controller will run by itself.
