RT-1070 He's Back! New RT1070

[Mozekian]

After the 5+ minute shutdown, do you ever see smoke coming out for several minutes later?

I do on my 700 and 1250. Usually I bring it down to 250-300 before starting shutdown. I know RecTeq says you dont have to but I think it performs better when I bring it down. I think they know it performs better when you do as well, but they are selling "convenience", so I get it.

And yes, I always see some amount of smoke coming out after shut down, nothing alarming, but when I open the grill to scrub after shutdown, I get some smoke coming out. But I would expect that with the fact they are igniting pellets, running the fan, and then it stops...you are going to get some residual smolder from the partially charred pellets, right?

 

[Cal1319]

After the 5+ minute shutdown, do you ever see smoke coming out for several minutes later?

Out of the smoker or the hopper? On occasion I have seen some smoke coming out of the smoker but just little and for little amount of time…

 

[SmokeZilla]

I have been lurking on this thread and it has been quite interesting. There seems to be two distinct camps. Those that have the issue and those that don’t. I have a 2+ year old Bull with the old auger motor and the “as issued” firmware. This combination has not given me any problems (knock on wood) and I cook at various temps (high and low) with different pellets, weekly. I think it would be helpful if those with problems could let us know the firmware, settings, and hardware configuration for your units. If RT is monitoring this concern, that may help further, especially for the RT1250 and RT10XX series of smokers. Also, if/when you are having problems, and trying to cool your grills, do any of you open the cooking chamber to allow excess smoke an easy point of escape instead of relying on the fan exclusively? Just wondering since I do both, leave it closed and wait for the fan to do what it is designed to do, and use the express method with it open so I can put it away sooner. My gut feel is that the “new and improved” units may not consistently behave. Any feedback is appreciated so I know what signs to look for.

 

[okie]

I asked for a reason. After some reading, testing and word of mouth, I think I have a better idea of :
if it happens
why it happens
why some folks are not aware when it does happen,
how to avoid it
a proposal to RT (if they are interested) as to how to avoid or make it not happen.

First off, I think we have underestimated the fire pot and what it is. It is basically a hot forge, where fire and air pressure are turned into high heat. All the heat being directed into the center of the pot it is directed upward to heat the pit. Fire and heat are directed in every direction, including into and around the auger and its tube. I imagine that there is at least 1000* generated in the center of the vortex (I've read that it is around 900*F or more). So even if the fire is not blown directly into the auger, the tube and its contents are subjected to enough heat to be able to ignite the pellets anywhere in the immediate vicinity, including not only the pot but also in the adjacent auger tube. I read that it only takes 300* to get wood to smolder and around 500* for spontaneous combustion to occur. So on a high temp cook, imagine the fire pot, auger tube and auger tip might even glow red to some degree. I am not sure of that but it seems reasonable.. Fortunately, the auger is pushing fresh pellets out all this time so everything is working for the chef.
Then as directed, he turns off the control, and for the next five minutes, the fan blows to help burn up the fire pot pellets, but no pellets are moved into the pot (that is the RT algorithm). During that time, those pellets inside the auger tube near the fire pot are burning and not moving out of the auger. The fan goes off after five minutes, and the auger comes on for 30 seconds to push the hot embers inside the auger out into the pot and long enough time to push fresh pellets on top which with no fan will choke out the remaining embers essentially smothering them. Sometimes it works and sometimes it does not.
What happens next, I think, is this:
1. The embers in the pot may smother or may not and thus allow the unburnt pellets to ignite.
2. Also, I believe that there is still a hot enough auger tube and auger tip that even if no embers remain in the tube, the pellets can ignite spontaneously from heat that remains. After all it has been fanned by fan and fire for 5 minutes, and it you take temps inside the pit it is often higher than when you turned the control off during those 5 minutes of fan only.
3. I noted on 3 occasions, that at the end of the OFF algorithm, that there was no smoke or sign of flame for several minutes before the smoke started appearing again. I was puzzled by this. Then realized that the fire pot and auger tube are still probably hot enough to ignite pellets spontaneously. So perhaps initial shutdown is successful after all, and then the residual heat is enough to start pellets burning again in both the auger and the pot. In the auger it produces smoke because of low oxygen, and in the pot it eventually flames and burns the "smothering pellets". Sure enough if you let it burn itself out, there are no fresh pellets in the pot when it is over and the auger may or may not go out as well.
4. Some folks apparently have no problems after a high heat cook. May be the algorithm varies, maybe they have smoldering but pay no attention, and clean up after it goes out. But many of us do.

So what do we do about it?
1. Live with it. (no thank you)
2. Always turn the heat down to below 300 (250 works well). and let it drift down while you enjoy your meals and turn it off when the temp is down there for a little while. Works well for me. But can delay cleanup. Low temp allows time for all to cool off and prevent spontaneous ignition again.
3. See if RT could simply alter the shut down algorithm, so at the push of the "off" button, it would turn down the temp to 250, and let the pit get to 250 before the current algorithm starts. Then we don't have to do that ourselves, and at the same time, they no longer have complaints about the shutdown..
I am currently in the process of trying to communicate all the above to RT.
And of course I may be wrong about my conclusions above. Comments appreciated.

 

[C. Keeper]

I asked for a reason. After some reading, testing and word of mouth, I think I have a better idea of :
if it happens
why it happens
why some folks are not aware when it does happen,
how to avoid it
a proposal to RT (if they are interested) as to how to avoid or make it not happen.

First off, I think we have underestimated the fire pot and what it is. It is basically a hot forge, where fire and air pressure are turned into high heat. All the heat being directed into the center of the pot it is directed upward to heat the pit. Fire and heat are directed in every direction, including into and around the auger and its tube. I imagine that there is at least 1000* generated in the center of the vortex (I've read that it is around 900*F or more). So even if the fire is not blown directly into the auger, the tube and its contents are subjected to enough heat to be able to ignite the pellets anywhere in the immediate vicinity, including not only the pot but also in the adjacent auger tube. I read that it only takes 300* to get wood to smolder and around 500* for spontaneous combustion to occur. So on a high temp cook, imagine the fire pot, auger tube and auger tip might even glow red to some degree. I am not sure of that but it seems reasonable.. Fortunately, the auger is pushing fresh pellets out all this time so everything is working for the chef.
Then as directed, he turns off the control, and for the next five minutes, the fan blows to help burn up the fire pot pellets, but no pellets are moved into the pot (that is the RT algorithm). During that time, those pellets inside the auger tube near the fire pot are burning and not moving out of the auger. The fan goes off after five minutes, and the auger comes on for 30 seconds to push the hot embers inside the auger out into the pot and long enough time to push fresh pellets on top which with no fan will choke out the remaining embers essentially smothering them. Sometimes it works and sometimes it does not.
What happens next, I think, is this:
1. The embers in the pot may smother or may not and thus allow the unburnt pellets to ignite.
2. Also, I believe that there is still a hot enough auger tube and auger tip that even if no embers remain in the tube, the pellets can ignite spontaneously from heat that remains. After all it has been fanned by fan and fire for 5 minutes, and it you take temps inside the pit it is often higher than when you turned the control off during those 5 minutes of fan only.
3. I noted on 3 occasions, that at the end of the OFF algorithm, that there was no smoke or sign of flame for several minutes before the smoke started appearing again. I was puzzled by this. Then realized that the fire pot and auger tube are still probably hot enough to ignite pellets spontaneously. So perhaps initial shutdown is successful after all, and then the residual heat is enough to start pellets burning again in both the auger and the pot. In the auger it produces smoke because of low oxygen, and in the pot it eventually flames and burns the "smothering pellets". Sure enough if you let it burn itself out, there are no fresh pellets in the pot when it is over and the auger may or may not go out as well.
4. Some folks apparently have no problems after a high heat cook. May be the algorithm varies, maybe they have smoldering but pay no attention, and clean up after it goes out. But many of us do.

So what do we do about it?
1. Live with it. (no thank you)
2. Always turn the heat down to below 300 (250 works well). and let it drift down while you enjoy your meals and turn it off when the temp is down there for a little while. Works well for me. But can delay cleanup. Low temp allows time for all to cool off and prevent spontaneous ignition again.
3. See if RT could simply alter the shut down algorithm, so at the push of the "off" button, it would turn down the temp to 250, and let the pit get to 250 before the current algorithm starts. Then we don't have to do that ourselves, and at the same time, they no longer have complaints about the shutdown..
I am currently in the process of trying to communicate all the above to RT.
And of course I may be wrong about my conclusions above. Comments appreciated.

1) Only one person on this forum has successfully updated a older controller.
2) I think maybe increased CFM will allow better cooling and combustion of the pellets within the 300 second time allotment.

 

[okie]

1) Only one person on this forum has successfully updated a older controller.
2) I think maybe increased CFM will allow better cooling and combustion of the pellets within the 300 second time allotment.

Or just lengthen the fan time to 10 minutes would be fine. It would cool it down nicely.

 

[okie]

Or just lengthen the fan time to 10 minutes would be fine. It would cool it down nicely.

But that would take a factory mod. For now just turning down before turning off works well .

 

[okie]

I do on my 700 and 1250. Usually I bring it down to 250-300 before starting shutdown. I know RecTeq says you dont have to but I think it performs better when I bring it down. I think they know it performs better when you do as well, but they are selling "convenience", so I get it.

And yes, I always see some amount of smoke coming out after shut down, nothing alarming, but when I open the grill to scrub after shutdown, I get some smoke coming out. But I would expect that with the fact they are igniting pellets, running the fan, and then it stops...you are going to get some residual smolder from the partially charred pellets, right?

Right.

 

[SmokeZilla]

Interesting and well written synopsis. One thing I noticed with my RT700 that is ~2.5 years old is that following the cool down (high or low temp) when I check my firepot, it has a comfortable (i.e., ~tablespoon) of fresh pellets resting comfortably. No sign of partial burn or scorching. I wonder if the algorithm was changed and “optimized” for the new auger? Also, did they change the configuration of the burner’s rod and if so, is that change contributing to this issue? I don’t have a way to tell by user posts but I don’t remember seeing those of us with Gen 1 (Wifi built in antenna), Gen 2 (WiFi with external antenna), or the legacy RT680 Bull owners posting about this concern. Just wondering.

 

[SmokeOCD]

... if/when you are having problems, and trying to cool your grills, do any of you open the cooking chamber to allow excess smoke an easy point of escape instead of relying on the fan exclusively? Just wondering since I do both, leave it closed and wait for the fan to do what it is designed to do, and use the express method with it open so I can put it away sooner.

Leaving it closed, keeping the smoke in will kill the fire quicker as it cannot breathe. Same with the hopper smoke - if it's filled with smoke, the fire cannot ignite or spread - it needs fresh air (oxygen). This is a similar principle for the gravity fed charcoal smokers. The coals up the tube don't light until they fall out of the feed tube because they didn't have the necessary air, the feed tube is filled with smoke.

I think for all the troubleshooting threads if everybody could put their grill info at the bottom or in a sig that may be helpful. I too look for commonalities among the grills to find a pattern for the behavior.

 

[okie]

Interesting and well written synopsis. One thing I noticed with my RT700 that is ~2.5 years old is that following the cool down (high or low temp) when I check my firepot, it has a comfortable (i.e., ~tablespoon) of fresh pellets resting comfortably. No sign of partial burn or scorching. I wonder if the algorithm was changed and “optimized” for the new auger? Also, did they change the configuration of the burner’s rod and if so, is that change contributing to this issue? I don’t have a way to tell by user posts but I don’t remember seeing those of us with Gen 1 (Wifi built in antenna), Gen 2 (WiFi with external antenna), or the legacy RT680 Bull owners posting about this concern. Just wondering.

Not as common a problem in the old Gen1 590 but occurred in mine. The algorithm seems to be the same of 300 seconds of fan only, and 30 seconds of auger. I wonder if RT just extended the Fan only time if that would make the difference? Sounds simple and reasonable. If the problem is truly spontaneous recurrent combustion (due to retained heat) as opposed to continuous burning, then the extra cool down would make the difference. In fact I think it would help in either case.

 

[Dr.Floyd]

When were you a Navy Doctor?

I wasn't. I was a Hull Maintenance Technician. My doctorate is a PHD in computer and information security.

 

[C. Keeper]

I wasn't. I was a Hull Maintenance Technician. My doctorate is a PHD in computer and information security.

So much for getting my medical marijuana card

 

[Dr.Floyd]

So much for getting my medical marijuana card

As my wife likes to tell everyone. "He's not that kind of doctor".

 

[Waterboy]

I’ve had my 700 for 2 1/2 years and I’ve had smoldering pellets/smoke from the hopper enough times that I do the temp turn down before I shut it off. I don’t think it has anything to do with a new algorithm. It didn’t happen every time but often enough. At least the newer controllers could get a fix pushed out to them if RecTeq were willing to admit they needed to update the shutdown sequence. Somehow I doubt that will happen

 

[Greg Jones]

As my wife likes to tell everyone. "He's not that kind of doctor".

When I was diagnosed with cancer 10 years ago, it was unbelievable the medical doors that my wife opened on my behalf by saying it was Dr. Jones calling! Her doctorate is in higher education! Use it, don’t lose it I say!

 

[okie]

But that would take a factory mod. For now just turning down before turning off works well .

Agree for present inventory, but they could easily change the program for new inventory. One thing (only) that I liked about the Memphis control was that it had a socket for a thumb drive so they could send upgrades in programming to you on a thumb drive, and all you have to do is insert into the socket. Unfortunately the rest of the Memphis product that I had was POS.

 

[okie]

I asked for a reason. After some reading, testing and word of mouth, I think I have a better idea of :
if it happens
why it happens
why some folks are not aware when it does happen,
how to avoid it
a proposal to RT (if they are interested) as to how to avoid or make it not happen.

First off, I think we have underestimated the fire pot and what it is. It is basically a hot forge, where fire and air pressure are turned into high heat. All the heat being directed into the center of the pot it is directed upward to heat the pit. Fire and heat are directed in every direction, including into and around the auger and its tube. I imagine that there is at least 1000* generated in the center of the vortex (I've read that it is around 900*F or more). So even if the fire is not blown directly into the auger, the tube and its contents are subjected to enough heat to be able to ignite the pellets anywhere in the immediate vicinity, including not only the pot but also in the adjacent auger tube. I read that it only takes 300* to get wood to smolder and around 500* for spontaneous combustion to occur. So on a high temp cook, imagine the fire pot, auger tube and auger tip might even glow red to some degree. I am not sure of that but it seems reasonable.. Fortunately, the auger is pushing fresh pellets out all this time so everything is working for the chef.
Then as directed, he turns off the control, and for the next five minutes, the fan blows to help burn up the fire pot pellets, but no pellets are moved into the pot (that is the RT algorithm). During that time, those pellets inside the auger tube near the fire pot are burning and not moving out of the auger. The fan goes off after five minutes, and the auger comes on for 30 seconds to push the hot embers inside the auger out into the pot and long enough time to push fresh pellets on top which with no fan will choke out the remaining embers essentially smothering them. Sometimes it works and sometimes it does not.
What happens next, I think, is this:
1. The embers in the pot may smother or may not and thus allow the unburnt pellets to ignite.
2. Also, I believe that there is still a hot enough auger tube and auger tip that even if no embers remain in the tube, the pellets can ignite spontaneously from heat that remains. After all it has been fanned by fan and fire for 5 minutes, and it you take temps inside the pit it is often higher than when you turned the control off during those 5 minutes of fan only.
3. I noted on 3 occasions, that at the end of the OFF algorithm, that there was no smoke or sign of flame for several minutes before the smoke started appearing again. I was puzzled by this. Then realized that the fire pot and auger tube are still probably hot enough to ignite pellets spontaneously. So perhaps initial shutdown is successful after all, and then the residual heat is enough to start pellets burning again in both the auger and the pot. In the auger it produces smoke because of low oxygen, and in the pot it eventually flames and burns the "smothering pellets". Sure enough if you let it burn itself out, there are no fresh pellets in the pot when it is over and the auger may or may not go out as well.
4. Some folks apparently have no problems after a high heat cook. May be the algorithm varies, maybe they have smoldering but pay no attention, and clean up after it goes out. But many of us do.

So what do we do about it?
1. Live with it. (no thank you)
2. Always turn the heat down to below 300 (250 works well). and let it drift down while you enjoy your meals and turn it off when the temp is down there for a little while. Works well for me. But can delay cleanup. Low temp allows time for all to cool off and prevent spontaneous ignition again.
3. See if RT could simply alter the shut down algorithm, so at the push of the "off" button, it would turn down the temp to 250, and let the pit get to 250 before the current algorithm starts. Then we don't have to do that ourselves, and at the same time, they no longer have complaints about the shutdown..
I am currently in the process of trying to communicate all the above to RT.
And of course I may be wrong about my conclusions above. Comments appreciated.

Suggestion #3 actually would be better for them to just extend the Fan time to 10 min. (or so) before final pellet drop and shutoff. That would provide plenty of time for a good cool down before turnoff. I have sent my suggestions last pm. and await their comments. If none, fine, we can get along without a change, but new owners will have to be informed by outside sources.

 

[FF Cory]

I asked for a reason. After some reading, testing and word of mouth, I think I have a better idea of :
if it happens
why it happens
why some folks are not aware when it does happen,
how to avoid it
a proposal to RT (if they are interested) as to how to avoid or make it not happen.

First off, I think we have underestimated the fire pot and what it is. It is basically a hot forge, where fire and air pressure are turned into high heat. All the heat being directed into the center of the pot it is directed upward to heat the pit. Fire and heat are directed in every direction, including into and around the auger and its tube. I imagine that there is at least 1000* generated in the center of the vortex (I've read that it is around 900*F or more). So even if the fire is not blown directly into the auger, the tube and its contents are subjected to enough heat to be able to ignite the pellets anywhere in the immediate vicinity, including not only the pot but also in the adjacent auger tube. I read that it only takes 300* to get wood to smolder and around 500* for spontaneous combustion to occur. So on a high temp cook, imagine the fire pot, auger tube and auger tip might even glow red to some degree. I am not sure of that but it seems reasonable.. Fortunately, the auger is pushing fresh pellets out all this time so everything is working for the chef.
Then as directed, he turns off the control, and for the next five minutes, the fan blows to help burn up the fire pot pellets, but no pellets are moved into the pot (that is the RT algorithm). During that time, those pellets inside the auger tube near the fire pot are burning and not moving out of the auger. The fan goes off after five minutes, and the auger comes on for 30 seconds to push the hot embers inside the auger out into the pot and long enough time to push fresh pellets on top which with no fan will choke out the remaining embers essentially smothering them. Sometimes it works and sometimes it does not.
What happens next, I think, is this:
1. The embers in the pot may smother or may not and thus allow the unburnt pellets to ignite.
2. Also, I believe that there is still a hot enough auger tube and auger tip that even if no embers remain in the tube, the pellets can ignite spontaneously from heat that remains. After all it has been fanned by fan and fire for 5 minutes, and it you take temps inside the pit it is often higher than when you turned the control off during those 5 minutes of fan only.
3. I noted on 3 occasions, that at the end of the OFF algorithm, that there was no smoke or sign of flame for several minutes before the smoke started appearing again. I was puzzled by this. Then realized that the fire pot and auger tube are still probably hot enough to ignite pellets spontaneously. So perhaps initial shutdown is successful after all, and then the residual heat is enough to start pellets burning again in both the auger and the pot. In the auger it produces smoke because of low oxygen, and in the pot it eventually flames and burns the "smothering pellets". Sure enough if you let it burn itself out, there are no fresh pellets in the pot when it is over and the auger may or may not go out as well.
4. Some folks apparently have no problems after a high heat cook. May be the algorithm varies, maybe they have smoldering but pay no attention, and clean up after it goes out. But many of us do.

So what do we do about it?
1. Live with it. (no thank you)
2. Always turn the heat down to below 300 (250 works well). and let it drift down while you enjoy your meals and turn it off when the temp is down there for a little while. Works well for me. But can delay cleanup. Low temp allows time for all to cool off and prevent spontaneous ignition again.
3. See if RT could simply alter the shut down algorithm, so at the push of the "off" button, it would turn down the temp to 250, and let the pit get to 250 before the current algorithm starts. Then we don't have to do that ourselves, and at the same time, they no longer have complaints about the shutdown..
I am currently in the process of trying to communicate all the above to RT.
And of course I may be wrong about my conclusions above. Comments appreciated.

Great synopsis. I think you’re on the right path. I hope that RT listens to what you have to say and their techs get with you. As a FF I understand the ignition temps of wood and the way fire reacts and I believe you’re spot on. I will be watching to see what you hear back. Thank you for your evaluation.

 

[okie]

Appreciate your support. I am waiting RT’s response.