Auber 20 cfm fan doesn't shut off?


 
N

NickMV

TVWBB Fan
I've got a auber 20cfm hooked up to our pit, but for some stupid reason at 0% the fan is still running.

Any ideas how to fix, if there is a fix? Works fine with my 6.5cfm auber fan.
 
Well, it's not the fan, that's for sure....The HM should cut the power to the fan, if the fan is running the HM is feeding it power. It could be your wiring or something wrong with the HM build.... The CENTER two pins on the CAT5 jack are the blower wires, Pin4 is the ground and Pin5 is the blower power. Pin 3 is the +5v power for the servo, so if you happened to put the blower wires across pin 3-4 then you would be putting steady 5VDC to your blower.

So check your wiring, if you're using the right pins then you should move on to troubleshooting the HM build... Posting good pics of the front and back side of the board is usually the quickest way to get help fixing things up....
 
It's the heater meter, as I can stop the fan manually for a few secs before it overcomes resistance and starts spinning again. It's def getting power.

I ended up restricting flow elsewhere on the pit to maintain control, since we had 60 lbs of meat cooking and extensive troubleshooting wasn't possible. I ended up unplugging the fan when the temp got high, seemed to be pretty stable.
 
If the controller works fine with another fan, it doesn't seem likely it is the controller. Did you check the wiring on the big fan?
 
VMastros said:
If the controller works fine with another fan, it doesn't seem likely it is the controller. Did you check the wiring on the big fan?
Click to expand...

Ah, well, there's nothing in any fan that can make it spin when there is no power applied to it, and when the HM has the blower speed set to 0% there should be no power applied to the blower if things are working right... So the problem isn't the blower, it's gotta be either your CAT5 wiring is wrong or the HM has problems.....

POST PICS OF YOUR BOARD and maybe we can help identify the issue. Likely a part installed backward or in the wrong place or a solder bridge or something like that, many times this stuff can be spotted by someone with experience in a photo.
 
RalphTrimble said:
Ah, well, there's nothing in any fan that can make it spin when there is no power applied to it, and when the HM has the blower speed set to 0% there should be no power applied to the blower if things are working right... So the problem isn't the blower, it's gotta be either your CAT5 wiring is wrong or the HM has problems.....
Click to expand...

My fan runs when there isn't any power too. Try this, remove the fan from the smoker and see if it still runs when there isn't any power applied. My guess is that you have enough convection running through your smoker that it is pulling air through your fan causing it to spin. That means you (and me) are probably a great candidate for a damper of some sort.
 
OK, the fan is spinning but not "running".... I guess that could happen from convection, and you're right, some sort of damper is what you need to stop that, that's what I designed the roto damper for....
 
It's not convection, as I can physically unplug the fan and it stops and stays still.

I guess I'll get a multimeter and check to see what's going on at 0% output, because obviously it's getting power. Regardless I'll likely move toward a damper solution for next year when we compete. The 6.5cfm fan stops just fine for my WSM so I have no need for a damper there.
 
So are you saying the 6.5CFM fan stops but this other fan doesn't, with the same heater meter? That would truly be odd.... I have never measured the voltage output on the blower when at 0% cause I've never had a reason to, but I assume its 0V or something pretty close to that, certainly shouldn't be enough to make a blower spin....
Have you tried switching the blower mode to see what happens? Try pulse mode VS voltage mode, if it shuts off in pulse mode then perhaps you have an issue with the feedback circuit. I think I recall reading something about a capacitor that is on the auber blower? Maybe that could be screwing up the feedback circuit? I don't know, drawing at straws here....
 
Edit: Ok so I swear I saw the 6.5cfm stop at some point (only 1 cook done with it so far), but nevermind.

I think I have a wiring issue. Would incorrect CAT5 wiring to the fan cause this? Or am I looking at a board or output jack issue more likely?
 
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The CAT5 jack has 4 connections....
Ground
Blower Signal/Power
+5VDC for servo
Servo PWM Signal

So if you have used the +5VDC wire and ground instead of the Blower Signal/Power and ground, or have a solder bridge on those pins, then yes your CAT5 wiring could be the problem... Did you try PULSE Mode for the blower?
 
Mine's a 4.1 board so I don't think it supports pulse, correct?

Anyway, I'm going to take it apart tonight and check out the wiring to see what's going on.
 
Actually it ONLY supports pulse..... The feedback circuit that is required for VOLTAGE mode was added on the HMv4.2, so you don't have it. "There's your problem".... Set it to PULSE and see if it turns off...


PS Just to be clear, ALL versions of the Heater Meter work with the blower in PULSE mode, that was the original way of driving the blower. The new VOLTAGE mode was added when HMv4.2 added the blower feedback circuit to the ATMega, VOLTAGE mode will NOT work with any HM older than V4.2. Voltage mode was added because it generates less noise/interference than pulsing the blower. Any time you are having an issue with the blower I recommend that you reset to PULSE mode first which eliminates the need for that feedback circuit.
 
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Haha wow, yep that was it! Talk about embarrassing, haha. I quickly stripped wires apart on the Cat 5 and sure enough I was using orange and brown instead of the green.

Anyways, I just performed a test and it cut off. Perfect! Thanks for your help, and I think it's funny that it performed so well so far considering i had wrong wiring.
 
So was the problem setting voltage mode in the config or did you have the wrong wires connected to the blower? (or both)
 
Sorry, missed your post between my last one and didn't realize you had commented.

The wiring on the Cat5 was off. I had servo control and ground instead of fan control and ground. And I've had it on pulse for a while, actually.
 
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