The wood pellet grill/smoker market is more competitive than ever before. Traeger as the original pellet BBQ manufacturer is having up their game to make sure their products stand out from the competition in their features and capabilities. Therefore, Traeger has updated the pellet auger and induction/combustion fan motors fitted to their range of pellet grills along with a new range of D2 control panels which include WiFire technology. With this post, I want to discuss what improvements Traeger has made with the D2 Direct Drive system and how it differs from the pellet auger and fan motors fitted in previous generation of Traeger pellet grills.
The new D2 Direct Drive system is now fitted to all Traeger models in the Timberline, Ironwood and Pro Series pellet grill ranges. Not all Traeger models such as their portable pellet grills including the Tailgater and Scout or Range pellet grills feature the D2 Direct Drive system. Though that will likely change in the coming months/years.
Traeger D2 Direct Drive Introduction
The basic function of how a pellet grill works starts with a hopper holding a certain quantity of BBQ wood pellets. At the base of the hopper, there is an auger (screw) which is powered by an electric motor. When the pellet grill is turned on and the temperature is set wood pellets will be fed into a firepot. A hot rod igniter then heats up those pellets until a fire is started. At the same time, an induction/combustion fan is providing air. The fuel and air mixture/percentages will dictate the temperature the grill achieves and also the quantity of smoke produced.
Now, this same basic process is how earlier generations of Traeger pellet grills worked along with the current generation featuring D2 Direct Drive and D2 control panels. However, when you start to look into the detail of components used on previous and current generation Traeger pellet grills fitted with D2 Direct Drive that’s where it becomes interesting. Though first below I’m going to discuss the components used in earlier generation pellet grills. Its much easier to understand where Traeger is going when you understand where they have been.
Earlier/Previous Generations of Traeger Pellet Grills
So all Traeger grills require a source of AC power, whether its coming from the mains or a 12V DC supply via an inverter as discussed in my Traeger accessories post. Well in previous generations of Traeger pellet grill all the components/motors within the grills were also AC. What that means is the auger motor and induction/combustion fan can simply be turned on and off via the control panel. When you set a temperature on the Traeger control panel it would turn the auger and induction fan on and off based on a timed setting to achieve a certain temperature.
The Traeger Renegade is a pellet grill still sold today with the previous generation Pro Series controller and AC auger/induction fan motors: Image – Amazon
Within the grill is an RTD temperature sensor which lets the pellet grill controller know once that temperature has been achieved. When the internal temperature of the grill matched the set temperature on the dial the control panel would stop the timed on/off power cycle for the auger and fan motor. If the temperature dropped say around 25 degrees from the set temperature it would start the off/on power cycle until the set temperature was achieved again.
This is the first generation Traeger Pro Series controller: Image – Amazon
While the AC motors were a relatively straight forward and simple means of achieving some level of temperature control in a pellet grill, they are not the most efficient or accurate means to do so. For instance, the AC auger motor and the AC induction fan motors in pervious generation Traeger pellet grills (and several other brands of pellet grill) were both controlled by the same power output from the controller. Hence, the control panel couldn’t turn on the auger or induction fan on/off separately, they were either both on or both off. This limited the previous generation Traeger pellet grills ability to achieve and maintain a set temperature accurately.
AC brushed motor for moving the pellet feed auger fitted to previous generation Traeger pellet grills: Image – Amazon
Furthermore, the AC motors fitted used brushes. What that means is to complete the connection and feed electrical power to turn the motor a carbon-graphite ‘brush’ is used as a wearing part. Hence, eventually, the brush will wear out and need to be replaced. However, in many cases, it was cheaper and easier to just replace the whole auger motor or induction fan.
The D2 Direct Drive Platform Fitted To Current Traeger Pellet Grills
While Traeger pellet grills fitted with the D2 Direct Drive platform along with the D2 controllers still require a source of AC power to operate the grills, its important to note that the D2 Direct Drive system runs on DC (Direct Current) and not AC (Alternating Current) power. Therefore, the D2 Direct Drive system can use DC motors, specifically 20V DC motors. The key benefit being that the motors for their size provide more power/torque. So for instance, the auger motor as part of the D2 Direct Drive system fitted in the Timberline, Ironwood and Pro Series pellet grills is less prone to suffering auger blockages. Its also important to note, on the D2 Direct Drive system the auger can actually go backwards for a short time if a blockage is detected. How would the D2 controller know a pellet auger blockage is occurring? Well, the amps (power) the auger motor consumes would start to increase due to the resistance above normal levels, indicating a blockage.
The Benefits of Variable Speed DC Motors
Another important upgraded as part of the DC foundation which the D2 Direct Drive system is built on is variable speed motors. This includes the combustion fan along with the auger motor. The benefits of variable-speed motors are two-fold. First, it enables much more accurate control of the temperature within the grill to within 5 degrees apposed to 25 degrees on pervious generation Traeger pellet grills. The second benefit is faster warm-up and response times. For instance, with the D2 Direct Drive system on startup (after ignition), the speed of the auger motor and induction fan is set to max speed. However, as the pellet grill starts to approach the target temperature the speed of the auger motor and induction fan is slowly reduced, so not to overshoot the target temperature. This ability to rapidly heat the pellet grill up to the set temperature is referred to by Traeger as TurboTemp.
Another benefit of TurboTemp is when you have to open the lid on the pellet grill to attend to the meat, fish, vegetables etc to turn them or add sauces/rubs. Once the lid is open heat is escaping and the internal temperature of the grill will drop below the target temperature. Well, put simply, a modern Traeger pellet grill with D2 Direct Drive/TurboTemp is able to get back up to the set target temperature much more quickly than the previous generation Traeger pellet grills.
Independent Auger and Fan Speed Adjustments
As noted above, with the previous generation Traeger AC auger and fan motors they were single speed which the controller could just turn on and off. However, they were also on the same circuit. Therefore, the controller could not independently turn the auger motor or fan motor on independently. Well, on the Traeger D2 Direct Drive system D2 controller can now independently control the auger motor and fan more on top of them being variable speed. Therefore, the controller can make small or large adjustments to the fan speed of the auger and fan motors independently.
The D2 system is what makes the ‘Super Smoke’ feature found on Traegers Timberline and Ironwood pellet grills possible. Its also an integral feature of the PID capabilities of the D2 controllers. What is PID? Well, it stands for Proportional Integral Derivative. In the simplest terms, its a constant feedback loop which frequently adjusts to the speed of the pellet feed auger motor and induction fan to maintain a set temperature. If you want to know more about how a PID controller works, I’ve included the video below.
Conclusions on Traeger’s D2 Direct Drive System
The new D2 Direct Drive DC independent brushless motor platform for the auger motor and induction fan in Traeger pellet grills is up there with the best pellet grilling/smoking technology currently available. Its a significant improvement over the on/off AC auger/fans motors used in previous generation Traeger pellet grills. Along with the PID D2 Controller Traegers pellet grills have never before been able to achieve and main their set temperatures to the same degree. The D2 controller can also accommodate the Traeger pellet sensor. Now, Traeger is not the only manufacturer with PID controllers, for instance, they are fitted to the Camp Chef Woodwind pellet grills and the Camp Chef Gen 2 WiFi controller. However, in terms of a complete package, the new D2 Direct Drive and D2 Controller from Traeger is arguably the best in the business right now.
However, I do want to make a quick note. While the new D2 Direct Drive DC auger motor is more powerful and more capable of resolving a pellet auger blockage its not infallible. If you let water (rain) into the wood pellet hopper on the grill and the wood pellets expand (go bad) there isn’t a pellet auger fitted to any pellet grill that won’t block up. So please bear that in mind, and handle your BBQ wood pellets with care.
That’s it! Thanks for reading, I hope this post has explained the Traeger D2 Direct Drive system to the level of detail you were looking for. If you are interested in reading more of my posts on pellet grills, please review my wood pellet grill/smoker guide. 🙂