US Stove 5500M, how to slow down feed rate?

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tlc1976

Minister of Fire
Oct 7, 2012
1,305
Northwest Lower Michigan
Hello. I have been lurking here for awhile. My gf just bought a US Stove 5500M from Tractor Supply about a month ago. Got it installed and running about 2 weeks ago into a 1456 sq ft modular house, and it was a cold wet weekend. It basically cooked us out! We had it on heat range 1 and all else on automatic. We had the windows open and were still getting cooked out! She tried it again a few nights ago and same thing, got cooked out.

I have read some things in here about hidden settings in the control panel, thermostat hookups, etc. So last night I was there and it was getting cold so we fired it up and I figured I'd look for those control panel settings and try to lower the feed rate. I couldn't get anything to show up! The panel dimmed a bit when I held the Heat Range Down button and repeatedly pressed the Aux Down button, so it seemed like it may have been doing something. It also seemed to be burning slower and cooler, but hard telling for sure since the display told me nothing.

I am only at the house about twice a week so I don't have a ton of time to tinker with it or I would. She isn't there a lot either so we were hoping to be able to just let this thing run at a very minimal setting and save a bunch of money over electric or propane. And besides being too hot, going though a bag of pellets every 20 hours will cost the same as the EdenPure.

Any tips on trying to lower the feed rate? Was I doing something wrong or do I just blindly press buttons and hope it worked? A thermostat would be ideal to add, but from what I read it only hops between heat range 1 and 5, and until I can tone down heat range 1 then it won't do any good.

I have thought of trying different things if I had more time, like inserting a delay timer to fake a tripped thermostat or door switch or whatever. I can do it no problem but the experimenting with the stove itself is what I don't have the time for.

Thanks
 
If an Edenpure is enough to heat the place, then you don't need a pellet stove. Consider yourself lucky. But, somehow I doubt the Edenpure is going to be enough in January unless you live in the southern half of the country. I took a look at your stoves manual and 2lbs/hr is the feed rate on low. Sounds like you are already on low if you are using a bag in 20hrs. Might have to wait until colder weather and then you might be able to run the stove w/out overheating the house. Until then just fire it up when cold and then shut it down. BTW the aux button only brings the stove back to factory default.
 
The EdenPure basically keeps it to about 60F max with all but 3 rooms blocked off, and on very cold days the propane takes over. We had to bundle up in the house. We would really like to ditch the propane entirely and heat the whole house and keep it more like 70F. She bought it and I helped choose it since the specs said 800 to 2000 sq ft. It was just snowing a couple hours ago.

Like you I just did the math on the feed rate. We didn't actually check and see if it went through a bag in 20 hours.

I have no problems modding this stove, just would like to have more time there to actually do it, and working with this fancy control equipment is a hindrance. But I have plenty of time to get my research done at home. It would be ideal to just keep it running at a lower feed rate, not having to restart it all the time. Maybe even put the auger delay button on a pulse timer, that way I am keeping it running and using the features of the board. I could also put the whole stove on a timer and cycle it on and off, with a separate trigger for the power button every time, that would be more work and would use more electric and wear the ignitor more. If all else fails I will figure out a way to do it eventually.

I was just wondering if there were any other easier ways and hidden settings, since I have seen it discussed in here from time to time.

Thanks
 
From a post by Member Polish Princess (this was dealing with her USSC furnace, some of which use the same controller as their stoves, controllers change on these stoves almost faster than one changes ....)

Steps to adjust
Press ON button
Press Heat Range and Aux button at same time----Should say 6.50 which means is set to burn 6.50 lbs per hour
Press the AUX DOWN button to 4.50 lbs per hour. If still too fast and too much waste in burn pot----LOWER again by .50 until reach desired amount of distribution.

Your starting amount is likely to be lower than the 6.5 on her furnace but I think you get the drift. It is possible that your stove got out of the barn with the wrong feed rate programmed into it (I don't know exactly which rate this was and if there are two rates a high and low in the controller that you can change.

I would talk to USSC to get the specific information you need.
 
One thing to keep in mind is that below a certain lbs/hr the stove might have a hard time staying lit and the fire will burn out. You have some interesting ideas on modding the stove to work the way you want. Adding a thermostat to a stove not designed for one is way beyond my electronic abilities, so good luck on that.
 
Why not just hook it up to a thermostat so the stove cycles on/off as needed , thus eliminating the cooking you out of the house issue ? Plus you should save on pellets.
 
I played with it a lot last night and well nothing seems to happen when you push AUX and Heat Range at the same time. It might have worked because the house didn't seem near as hot but the controller didn't really do anything so I was just working blind. Maybe the version of controller is different. Finding an older model controller to plop in that really does that would be tough but the most ideal option.

The stove does have the option of an add-on thermostat. But what it would do with one is toggle from heat range 1 to heat range 5. Since heat range 1 is too hot to begin with, the thermostat that way would do no good.

I have thought of many ways to delay different things, but would not want to screw up the auto management of the draft fan. If I delayed or slowed the auger motor itself then it would probably give too much air because the controller wouldn't know any different. I could easily put a timer on the power cord, but with the electronic panel, you still have to turn it on after replacing the power which is the kicker. But the plus is that it would run super hot and efficient when it does run. Edit: Another idea, if I used a timer to just kick the thing on and off using the power buttons instead, that might work.

So I am thinking to just hardwire a pulse timer to the contacts of the auger delay button. That way I am still letting the stove do it's thing. Since the delay lasts 1 minute, a pulse every 2 minutes would roughly half the overall feed rate no matter what the heat range setting. Then we could still turn up the heat range if needed, or heck even add the thermostat that we wanted to begin with.

Thanks
 
I played with it a lot last night and well nothing seems to happen when you push AUX and Heat Range at the same time. It might have worked because the house didn't seem near as hot but the controller didn't really do anything so I was just working blind. Maybe the version of controller is different. Finding an older model controller to plop in that really does that would be tough but the most ideal option.

The stove does have the option of an add-on thermostat. But what it would do with one is toggle from heat range 1 to heat range 5. Since heat range 1 is too hot to begin with, the thermostat that way would do no good.

I have thought of many ways to delay different things, but would not want to screw up the auto management of the draft fan. I could easily put a timer on the power cord, but with the electronic panel, you still have to turn it on after replacing the power which is the kicker. But the plus is that it would run super hot and efficient when it does run. If I delayed or slowed the auger motor itself then it would probably give too much air because the controller wouldn't know any different.

So I am thinking to just hardwire a pulse timer to the contacts of the auger delay button. That way I am still letting the stove do it's thing. Since the delay lasts 1 minute, a pulse every 2 minutes would roughly half the overall feed rate no matter what the heat range setting. Then we could still turn up the heat range if needed, or heck even add the thermostat that we wanted to begin with.

Thanks


tlc1976,

Please read the post I made about adjusting the fuel feed rate on a USSC unit (depends upon the controller in your stove if that will work).

There is nothing you can do except through the controller to prevent fouling up the draft/fuel feed situation.

The best information will come from USSC and you might have to pull teeth to get it.


Gio,

That stove only has hi/lo mode for t-stat usage.
 
tlc1976,
I don't know if you found this thread or not. It is for a 5510 but I'm pretty sure the controller and most of the rest of the stove are pretty much the same as the 5500 except the 5510 has an ash pan underneath. On page 5 Whallila has an excerpt from a troubleshooting guide from USSC called Adjusting Operational Constants. You need to scroll most of the way down the page to find it. This info worked great on my 5510. I lowered the feed rate on heat range 1 to 1.4 pounds per hour. I did this while my stove was off, I'm not sure if it will work when the stove is on.

https://www.hearth.com/talk/threads/king-5510-review.41617/page-5
 
It`s definitely possible that low heat settings especially for prolonged periods of time can lead to other major stove issues , not to mention reduced efficiencies.
I do believe running my stove on low caused the auger tip to disintegrate and heavily contributed to the the "gummy stove syndrome".
I also have decided that my next stove purchase will absolutely be thermostatically controlled and with shut -off/ re-start capability to maximize efficiency and save on fuel.
 
It`s definitely possible that low heat settings especially for prolonged periods of time can lead to other major stove issues , not to mention reduced efficiencies.
I do believe running my stove on low caused the auger tip to disintegrate and heavily contributed to the the "gummy stove syndrome".
I also have decided that my next stove purchase will absolutely be thermostatically controlled and with shut -off/ re-start capability to maximize efficiency and save on fuel.

Master Chief PO,
I definitely agree with you about the t-stat idea. I'm looking at stoves right now with the on-off/low-high function. Which stove did you have the problems with? My 25-PDVC ran on low almost all of the time over the last five years (about 2.5-3 tons per year) with no problems at all. Never even an auger jam (I hope I didn't just jinx myself :rolleyes:). I usually burn green label Ligs. My 5510 runs High-Low on a stat going between ranges 1 and 3 on the same pellets. No problems so far except a couple ignitors and air leaks... I wonder how the OP is making out?
 
I didn't realize there were new posts, my email didn't keep me updated on the thread anymore.

I had not found that linked page about the 5510, very much thanks! I'll see if I can get a hold of the whole manual since it doesn't appear that Whallia is an active user anymore. That would be the easiest thing and we could at least try it. Those are different button sequences than posted before so I am hopeful. I'd just have her try it tonight but she is kinda freaked to screw it up. One thing, how do you do it with the stove off? Doesn't the panel only work with the stove on? But it does have power to it or the buttons wouldn't work. I will certainly try that along with the other method with the stove off. That just might be the ticket!

Yes I totally understand about the reduced feed rates and how it might gum things up after awhile. Similar to my woodstove how I have to choke it down because I am gone a lot as well, and I have to clean the pipe ridiculously often. However I was thinking that if you let the computer do it and regulate the draft fan and all, it should burn efficiently when it does burn, then cut back. I guess we will see.

If the control panel adjustments still are not available, then I am looking into building a simple 555 timer circuit to do something or other, and want to have it ready for next week when I go over there. Very busy week for both of us and therefore will have no time till next week. I have been thinking to use it to "press" the auger delay button every couple minutes, or to simulate the hopper door open switch being tripped every couple minutes thus cutting fuel. Anything that does not cause an error code and kill the stove when we are gone. Then with the overall feed rate cut down on all heat ranges, I could hook up a thermostat in the intended fashion, so it would go between high and low. When it runs in high, it would at least burn off the buildup I would think.

Or possibly just do the most efficient thing, which would be to make the timer "press" the on and off buttons at intervals every hour or two or whatever, adjustable with a variable resistor. That way it would burn super efficient, then shut down and start up doing its own programmed proper sequence. More wear on the ignitor and electric use by using the ignitor, but since the stove will be warm already hopefully not too much energy and wear. Our key is efficiency, we got this thing to save money in the long run while keeping the house warmer.

Thanks for the continued advice everyone.
 
Master Chief PO,
I definitely agree with you about the t-stat idea. I'm looking at stoves right now with the on-off/low-high function. Which stove did you have the problems with? My 25-PDVC ran on low almost all of the time over the last five years (about 2.5-3 tons per year) with no problems at all. Never even an auger jam (I hope I didn't just jinx myself :rolleyes:). I usually burn green label Ligs. My 5510 runs High-Low on a stat going between ranges 1 and 3 on the same pellets. No problems so far except a couple ignitors and air leaks... I wonder how the OP is making out?
My Harman P-38 was the stove with the burned out auger tip from running it on low for long periods of time. (days and weeks at a time)
I thought it was cool to get 40 hrs + from one bag but in the long run it can`t be worth it with regards to the issues it causes and when compared against a stove that runs on/off with a thermostat. Presently I`m running it less but dialed up hotter . Starting a manual stove twice a day is getting to be a PIA too.
I don`t think the 25 PDC will have the auger burn out problem since it turns constantly vs intermittent as on the Harman.
 
I have 2 schools of thought today and I am wondering which way I am going to go. I am going to do one or the other, either is very doable and I can have it built and install it on a night next week. Both ways I plan to use a thermostat and either tap it off the board (if changing the board settings) or off my controller if I make a timer circuit. Temps can vary so greatly around here and we are gone so long, if it is 20F in the morning and gets to 70F by afternoon then what good is that without a thermostat?

#1 is to keep the stove running but run it seriously reduced. Either with messing with the panel feed rate, or by building a timer to constantly keep delaying the auger. Even if I get the settings on the panel turned down, according to my calcs we will most likely be running on a seriously reduced heat range, something like 0.5-1.0 lbs/hr which is probably going to cause buildup and maybe wear down other crucial parts. Not to mention burning our pellets inefficiently. Of course there is the issue of keeping the fire going to begin with. If it goes out on its own due to too little fuel then it causes an error and shuts the stove down and then what good is that? So does anyone know with this stove if I am likely to burn up the auger or other parts by turning it so far down?

#2 is to tap into the power on and off buttons and let the stove do its own thing by firing up and shutting down. The thermostat will send power to my timer circuit and will fire a single 1 second pulse to trip a relay that closes the contacts of the power off or power on button as needed. Basically it will run on the heat range we set (usually 1), then shut down when it reaches room temp. Just like a furnace. Thankfully the stove has auto-start and auto-shutdown so we can just let it go. Based on our use so far, it will probably run a couple hours on, many hours off. Will run longer on as it gets colder. As long we can leave it on heat range 1 which seems likely, that should make the output more slow and steady and reduce the amount of cycles. Only real drawback of this method is more wear on the ignitor, and checking online these things are like $60 a pop. Does anyone know how long the ignitors in these things last, if cycled on and off several times a day?

#2 seems like the best way but I wonder how iffy the ignitors are when used a lot. Or if anyone knows if they can be had for cheaper. Also yes we were shooting for at least 40 hours per bag as well, and it seems #2 is the only efficient way to do that.

Thanks for the continued advice!
 
tlc,
You won't need to worry about burning or gumming up your auger because the 5500 is a top feeder as opposed to a bottom feeder like MasterChief's Harman and my 25-PDVC. Your auger drops the pellets down a chute whereas the bottom feeder augers push the pellets directly into the fire.

I would recommend trying method #1 first. On my 5510 I changed my feed rate on HR-1 (C-2 setting) from 1.75 to 1.38 lbs per hour and my Draft Fan Level on HR-1 (C-4 setting) from 100 to 150. Along with sealing the firebox better and replacing the door gasket I've gone from shutting down and cleaning the stove every day to at least 3 days between cleanings. I can go longer on lower ash pellets than the Green Ligs that I usually burn. My T-Stat alternates the stove between HR-1 & HR-3 and its burning very well and I'm going more than a day on a bag without turning the stove off. I calculated over 28 hours burning constantly on low.

I'm on my third igniter in 4 years and I spent about 2/3 of a season lighting manually so I'm not doing much better than an ignitor every season. You would have to keep that burn pot pretty clean to keep the igniter hole from being covered up by ash which would cause a misfire if you used a timer to start and stop it.

Just my .02 worth ==c
 
Tomorrow I am finally going to get a chance to go back and I have some plans.

I will look at the more recently found control panel adjustments.

I also plan to hook up the controller I made, regardless if I can do feed rate adjustments. I wanted to upload a pic but it is not cooperating right now. It runs through a cheap heat-only thermostat. It will trip the on or off buttons on the stove panel as the temperature changes, letting the stove burn efficiently, do its own start/run/stop cycle, and keep use down during the day when it warms up outside. This could probably be used with any stove with a control panel. I was checking out this Castle stove possibly for myself someday and it had a common button for on/off that would just toggle. I could easily make this controller work with that as well, with a single output timer/relay and a couple diodes off the thermostat relay. The thermostat and board will be tethered to the panel with probably phone wire and mounted far away from the stove, next to the furnace thermostat, and to read temps after the heat fills the room. I have been testing this controller vigorously and had to adjust for a couple glitches, but as of the revision a few days ago it is rock solid. It shoudn't toggle too much but I guess we will see how long an ignitor lasts. I think this is the most efficient way to go and therefore make the pellets last the longest.
 
Got it hooked up today and it works great! Tapping into the control panel was the trickiest part, it is set up like a computer keyboard with a matrix of connections. The connections are also at 80 ohms, not just plain contacts, which made it tricky to test. The panel basically divides into 3 pieces, and at the connections to the pushbutton board there is a 7 pin connector. Pin 7 and 3 are for the off button, and pin 7 and 4 are for the on button. The closest I had was a 100 ohm resistor so I put that off pin 7, and then connected my wires to that, along with the other pins. She happened to have several hundred feet of phone wire in the garage. There were already holes in the floor where we needed so we ran the wire under the house.

It really will just be a convenience. It is a total add on, you can still use the buttons manually and if you unplug the controller it will be like it is not even there. Or totally remove it easily if desired. If the burn pot gets dirty and it won't ignite then well it would be no different if you just pushed the on button and having it not go. May get to try to mess with lbs/hr later but for now what we have is great!

If anyone wants to make one, it is really easy and I think a worthwhile add on.
 
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Here we go. I guess I never clicked the more options button to find how to upload this. Photobucket doesn't work well for dialup.

This is mostly it, taken at my house before I took it over and installed it. I drilled two small holes in the bottom of the enclosure, one for the phone wire to the stove, the other for the wall wart power supply. Then the thermostat is screwed to the cover, centered to look nice. I also bypassed the anticipator because it really does no good for this application. Wish I had pics of it on the wall, and my hookup to the stove, but I was really under a time crunch to get it done and didn't have a camera. But my description should be self explanatory if you are ever into the panel.

The circuit is pretty much available online, I just had to apply it to what I was doing. The thermostat powers a relay to throw the power between the ON and OFF timers. Other than that, I originally followed another page which screwed me up at first but this page gave me perfect results.

http://home.cogeco.ca/~rpaisley4/LM555.html#29

Circuit 1 is the main circuit, except the output relay is wired NO instead of NC. As described earlier in the page, R1 is 1M ohms and C1 is 1uf to make the "button press" 1 second long which was easy enough. If it needs to be shortened or lengthened depending on the stove, just adjust the values of R1 and C1. I also put a .1 uf on pin 5 as recommended earlier in the page.

The wall wart puts about 15v and drags down to 13v during triggering. The thermostat relay is 12v because it is on during the whole heating stage and also is the first to receive voltage so no problems. The timer output relays are 9v, and only run 1 second at a time with a long time in between, so this makes them reliable when the voltage drops.

We have both been insane busy at work and yesterday was the first time I was over there in almost a month. But I checked it out and it is still working perfectly.


StoveControl1.jpg
 
Here we go. I guess I never clicked the more options button to find how to upload this. Photobucket doesn't work well for dialup.

This is mostly it, taken at my house before I took it over and installed it. I drilled two small holes in the bottom of the enclosure, one for the phone wire to the stove, the other for the wall wart power supply. Then the thermostat is screwed to the cover, centered to look nice. I also bypassed the anticipator because it really does no good for this application. Wish I had pics of it on the wall, and my hookup to the stove, but I was really under a time crunch to get it done and didn't have a camera. But my description should be self explanatory if you are ever into the panel.

The circuit is pretty much available online, I just had to apply it to what I was doing. The thermostat powers a relay to throw the power between the ON and OFF timers. Other than that, I originally followed another page which screwed me up at first but this page gave me perfect results.

http://home.cogeco.ca/~rpaisley4/LM555.html#29

Circuit 1 is the main circuit, except the output relay is wired NO instead of NC. As described earlier in the page, R1 is 1M ohms and C1 is 1uf to make the "button press" 1 second long which was easy enough. If it needs to be shortened or lengthened depending on the stove, just adjust the values of R1 and C1. I also put a .1 uf on pin 5 as recommended earlier in the page.

The wall wart puts about 15v and drags down to 13v during triggering. The thermostat relay is 12v because it is on during the whole heating stage and also is the first to receive voltage so no problems. The timer output relays are 9v, and only run 1 second at a time with a long time in between, so this makes them reliable when the voltage drops.

We have both been insane busy at work and yesterday was the first time I was over there in almost a month. But I checked it out and it is still working perfectly.


View attachment 81589

What I do not see?
How is this circuitry wired into the pellet stove? If the T-Stat connection does only Auto-Hi/Lo, then is your circuitry wired into the On/Off button? If so how is it physically connected if the On/Off button goes into a multi-layer circuit board?
 
It goes to the on and off buttons. The wires are soldered to 3 different pins of a 7 pin connector. The best way I could describe it is in my 2nd to last post. I know I wish I had a pic but if you pull one of these control panels apart it will make perfect sense.
 
I just wanted to post an update and this is still working flawlessly. It's been almost 2 months since the on/off thermostat install. I've been pretty slammed at work but got a chance to go spend some time over there today.

I did have an idea the other day which I am going to incorporate soon, hopefully by the end of the year. Currently, thermostat or not, if the power goes out, the stove will not restart on its own. I checked today and it takes about 12 seconds or so for the stove to go through the boot up sequence after the power resumes. So I am going to add another timer chip to delay the thermostat's initial power by a half minute or so. So if the power goes out and comes back on when nobody is there to tend the stove, this will give the stove a chance to boot up, then the thermostat will power up and turn on the stove if the room temperature calls for it.

Of course there are going to be some unburnt pellets in the burn pot but we are only running HR1 and so hopefully it should reignite pretty easily. It would be nice to test it first but I it's only a 3 wire hookup into the existing thermostat and can be made for a few dollars.

This thing just keeps getting better and better than stock!
 
Or, have a 555 timer driving a relay, and set it to a 50% On/OFF duty cycle. Then connect the NC relay contacts in series with the auger motor power. Then you would get half the feed rate. The intervals between relay cycles should be about as long as the intervals that the auger motor normally runs.
 
I thought of doing something like that early on, but others reassured me that doing anything to change the feed or draft outside of the control panel will make it not burn correctly. So I wanted to keep the auto-management of the burning, just control WHEN the stove burned. If it is 20F when we leave the house then by afternoon it is 70F then the stove is still running and wasting pellets, no matter how low of a feed it is set at. Or if it is warm when we leave, and the temperature plunges due to a cold front then that is no good either. The on/off thermostat is the most effective way to keep the house at the temperature we want, while saving money on pellets by using the stove only as needed. You get the best of both worlds this way. You get the savings of pellet heat, with the on-demand control of a gas furnace.

She cleans it once a week with the ash vac. I've done some of the cleanings and there is no need to scrape the burn pot or anything, it cleans quite nicely and the ash seems to be burned complete. About 6 weeks ago it used 3 bags in 2 weeks. Currently while it's cold and snowy it is going through about 3 bags a week. When it gets to the dead of winter it might go through a bag a day, we will have to see. But doing it this way, we only use the BTUs that are needed, and my figures showed that pellet heat is about half the price of propane or electric and the stove would pay for itself in a couple years. For the most part she keeps it in the mid 70s when she is home and awake, and 60 when at work and sleeping. After turning it down for the night, it doesn't kick back on until the middle of the night. The stat I used has an overall total swing of about 5 degrees so it doesn't cycle a lot anyway.

I'm not worried about the ignitor either. There are places online to get them very cheap and the factory one still works fine anyway. I am curious to see how long it lasts, and I have a spare sitting there in case it does go. Even if it turns out we go through a few ignitors a season we are still way ahead in savings. Besides I work with a couple guys who always complain about the ignitor burning out in their high efficiency gas furnaces every season so it's not just us pellet folks. These stove ignitors are cartridge heaters and are used in industry and are made to cycle regularly. We only run the stove on HR1 at least right now and that may make it last longer by not exposing it to the kinds of burnpot temps that a stove running on HR5 would see.
 
I know this post is old but I was curious how this has held up for you? I've got the 5502m now myself and was interested in doing the same thing.

Thanks
 
Not sure. She left me about a month after the last post and almost immediately married another guy. Never talked to her since. The main advantage to this would be shoulder seasons, and if you're got a large stove for a small efficient house (like she did). When it gets cold enough to where you need to run 24/7 then it wouldn't come into play.

Knowing what I know how, having run my own pellet stove for just about 2 years, the only drawback I can see would be increased ignitor wear. But you can get an ignitor (cartridge heater) from Zoro Tools for about $20, crimp on your own connectors, and be all set. If it saves you considerably more than $20 worth of pellets for what the ignitor lasts then you're ahead. I'm still on my original ignitor, and have sourced spares for whenever it does go out.

I've thought about doing this to mine some way or another. I've got the thermostat, and the memory of how I built the other one. Only thing is the board is different and I have a single button for on/off so things get trickier. I've also thought about just a full out manual control and slowing down the feed rate that way, and duplicating a burn pot with a narrower burn chamber so the fire won't go out.