INTRODUCING: the "Roto Damper"


 
I just installed my roto damper and wired it up. The servo is jumping around and not much changes as I attempt to manually adjust the damper. I have gone into configuration and set it from 700-2100 and made sure the invert box is unchecked. I've also tried for different ethernet cables. Anybody have any idea other than a bad servo?
 
Try the servo alone, outside of the RD3. If it still jumps around and does not make about 180 degree rotation when you go between 0% and 100% HM output then I would suggest you check your CAT5 jack wiring, or you may indeed have a bad servo.
 
If you're ordering an MG90S servo, I would warn that it's the most copied servo in existence. I would recommend ordering from a reputable vendor to make sure it is actually a Towerpro brand, and not a cheap Chinese knockoff. I order all of mine directly from Towerpro, but you'll have to send them an e-mail to get one. They have no price on their website.
 
My standard output cap for the RD3 fits all the BBQ guru adapter plates.... Shoot me an email at rotodamper AT Hot Mail DOT com and I will help you out....
 
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Just completed build out of HeaterMeter v4.2 w/RPi Zero W and Roto Damper RD3. Very impressed with the simplicity of build out, configuration, and operation. Thanks Bryan & Ralph for the effort put into developing, refining, and documenting this solution. Everything looks to be working beautifully!

Couple simple questions to anyone...

1). Am I correct to assume that when adjusting the low & high pulse values for servo operation, that I want the damper 100% open (meaning the two half moon ports are perfectly aligned to full open, max air flow) when fan is at 100% and when fan is at 0% the damper window alignment should be at that point where the port is just closed (no air flow), so that when fan goes increases from 0%, to lets say 5%, the port window just begins to open for air flow?

2). I have an offset smoker with the firebox on the right. In most all implementations of the HeaterMeter w/Roto Damper I see people installing the unit over the air intake damper door on the right side of the firebox. Is anyone aware of any issues if one were to install the Fan/Roto Damper RD3 under the main body of the smoker chamber into the left side of the firebox and just leave the right side air intake damper of the firebox closed?
 
I don't have any experience with #2, but you've got #1 right on. Just go into the config webui and set the setpoint to "0%", which will set you to manual mode, 0% output. Then use the servo pulse duration to make sure it is just closed. The HeaterMeter can only operate in increments of 10uS so don't worry about getting it to the perfect 1uS. Then set the setpoint to 100% and do the same thing except with the other value making sure it is just fully opened at your selected pulse length.

PROTIP: Use Alt-S (or Cmd-S on Mac?) on the webui config page to quickly "Save & Apply" the value rather than scrolling back and forth between the pulse fields and the Save button.
 
I agree with Bryan on #1, though some seem to think setting the zero point so the damper remains slightly open is better, I prefer zero=fully closed.

On #2, I am not sure I fully understand the question, but as long as the air is getting into the fire box it should work out ok. You want the air intake to blow as directly at the fire as possible. You want to avoid bringing the air in where it can blow right past the fire into the smoking pit, that can cool the pit initially rather than warm it, then give you overshoot when the fan slows down.
 
I think with #2 heat could become an issue. Just may want to see how hot that area gets. You'll have heat being radiated from both the bottom of the main chamber and the side of the fire box. Would be easy enough to fix with a heat shield. What about the right side of the fire box instead of the back as you're facing the fire box door? Seems like where you're suggesting the blower would be competing with the draft direction. Just brainstorming.
 
Hey all, I ordered the RD3 from Ralph a few days ago and am working on putting it together, but I feel stumped here. How the heck does one get the RJ45 jack into the control box. I know it's supposed to snap into it but that just ain't happening. Can someone assist with letting me know how it's oriented into the box, or tips on how best to snap it in. I don't think it matters, but I'm just using the basic setup. No RDTC board or anything.

I have yet to get to the wiring stage, but that'll come later.
 
I just looked around for my RD3 and I can't seem to find it to determine which way the jack is supposed to go, but I do remember it being an exceptionally tight fit. I think it has to go straight in rather than how you'd think it would be (which is to lever it in one side at a time). All the wiring has to be done before it snaps in though, because I think you'd have to break the snap side to get it back out once it is in. I've only ever built two of them though so maybe someone else can chime in about the orientation.
 
So, I am preparing to do a Heatermeter build. My smoker is a Brinkmann Cimarron offset smoker. Big and heavy. I am concerned about adequate airflow. Am I crazy to think a Cimarron requires more ventilation than a Webber or green egg? Does the RD3 have adequate CFM for my beast to breathe?
 
The RD3 lets the 6.7CFM blower push for all its worth... If 6.7CFM is enough for the Brinkmann Cimarron it will work, however, I have no idea how much air that smoker requires. I also have an RD25 which can run much larger blowers, but I dont think you would need that much flow. I'd be glad to help you out with the RD3 parts, and if the rig falls short will work out a deal to move up to the RD25. Shoot me an email at rotodamper AT HOT MAIL DOT COM if you are interested.
 

 

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