USSC 6220 delay in auger

[Iflyrctoo]

Ive been having a problem with my USSC 6220 Pellet Furnace. For the last 6 weeks or so, every time I shut it down for cleaning, I have a hard time getting it to start up again.
The problem is that upon lighting it, it just wont feed pellets for anywhere from 30 to 45 minutes. Eventually it starts feeding and it remains working fine for a full week till I shut it down again. Then the problem repeats.
Ive tried running the test procedures and the auger runs fine during the test. But during initial startup it doesn't even try to run for as I said, 30-45 minutes. Then it works normal. Ive done factory resets and run diagnostics till I'm blue in the face.
I thought it must be the circuit board was going bad as I was having a couple other minor problems. (numbers not lighting up and exhaust fan acting strange), so I just bought and installed a factory new control panel. All the problems were fixed except the auger feed on startup problem. It remains.
The vacuum switch tests fine and the thermistors are reading temps. Not sure they are reading the correct temps or how that might affect things. I guess I could use a infrared thermometer to check the readings against the thermistors readings in the test procedure.
Anyone have any other thoughts?

 

[gfreek]

Have you done a search on this forum ??
Here is a thread that may have some useful info..

USSC 6220 keeps shutting down.

I have a 6220 pellet furnace and suddenly it keeps shutting down with an error code 2. Strangely the fire seems to be going strong when it does this. Pellets are feeding fine, vacuum seems fine and the fire is hot. Stove feels like its up to operating temp to me but the room fan only comes on in...

www.hearth.com

 

[ARC]

Not sure they are reading the correct temps

You might be on the correct track. Are any lights blinking when trying to start up? How are you keeping fire going for 30-45 minutes? Hand feeding until auger starts? The On light and Aux light should be the only ones flashing. Look closely at Heat range and draft fan lights. If heat range flashing could indicate bad thermistors if draft is flashing could mean vacuum problem.

Flashing On Light: This means that the stove is in the “Start Up” state waiting for either a 3 minute
time-out to begin burning or for the stove to reach the warm temperature whichever comes first.

Flashing Off Light: This indicates that the stove is in the shutdown state waiting for the OFF
button, or for a 15 minute period after the stove was turned off, or for the stove to cool down, or for
the door to be closed.

Flashing Dash in Heat Range Display: This indicates that the stove is in normal run mode and is
ramping from the current heat range setting to the target heat range setting. Once the ramp is
complete the dash will stop flashing. For Ramping from heat range 1 to 5, the default time is 12
minutes (with a 90 second ramp time).

Flashing Automatic Mode Indicator: This indicates that the stove is in normal operation and is
running in the automatic mode. However either the draft fan or auxiliary setting is manually
configured.

Flashing draft fan: This indicates that the stove is in normal operation and that the vacuum sensor
detects a loss of pressure either because the door is open or because there is a negative pressure in
the room with respect to the exhaust.

Flashing Aux Indicator: This Indicates that the igniter is on during the lighting stage.

Quickly Flashing Heat Range Setting Indicator (changes twice per second): This indicates that
the stove is in normal operation and that an over-temperature condition exists causing the fuel to
stop.

Slowly Flashing Heat Range Setting Indicator (changes once per second): This indicates that
the stove is in a cut back condition in an attempt to prevent an over-temperature shutdown

 

[Iflyrctoo]

You might be on the correct track. Are any lights blinking when trying to start up? How are you keeping fire going for 30-45 minutes? Hand feeding until auger starts? The On light and Aux light should be the only ones flashing. Look closely at Heat range and draft fan lights. If heat range flashing could indicate bad thermistors if draft is flashing could mean vacuum problem.

Flashing On Light: This means that the stove is in the “Start Up” state waiting for either a 3 minute
time-out to begin burning or for the stove to reach the warm temperature whichever comes first.

Flashing Off Light: This indicates that the stove is in the shutdown state waiting for the OFF
button, or for a 15 minute period after the stove was turned off, or for the stove to cool down, or for
the door to be closed.

Flashing Dash in Heat Range Display: This indicates that the stove is in normal run mode and is
ramping from the current heat range setting to the target heat range setting. Once the ramp is
complete the dash will stop flashing. For Ramping from heat range 1 to 5, the default time is 12
minutes (with a 90 second ramp time).

Flashing Automatic Mode Indicator: This indicates that the stove is in normal operation and is
running in the automatic mode. However either the draft fan or auxiliary setting is manually
configured.

Flashing draft fan: This indicates that the stove is in normal operation and that the vacuum sensor
detects a loss of pressure either because the door is open or because there is a negative pressure in
the room with respect to the exhaust.

Flashing Aux Indicator: This Indicates that the igniter is on during the lighting stage.

Quickly Flashing Heat Range Setting Indicator (changes twice per second): This indicates that
the stove is in normal operation and that an over-temperature condition exists causing the fuel to
stop.

Slowly Flashing Heat Range Setting Indicator (changes once per second): This indicates that
the stove is in a cut back condition in an attempt to prevent an over-temperature shutdown

I will pay closer attention to the flashing lights at startup. Ive checked them before and some didnt make any sense at all. Even when running the diagnostic tests. Did not check them since the new control panel this weekend. Have to wait till I shut down again. Yes I have to manually feed pellets to keep it going till it decides to start feeding itself. So I dont want to shut down till I need to clean it again.
I cant believe its the auger motor as it works during the diagnostics and if I manually power it. Even putting a substantial load on it didn't stop it. It just isn't getting power on initial startup for 30 -45 minutes. Something is telling it not to feed and the control board is brand spanking new and does the same thing.

 

[ARC]

Something is telling it not to feed

A bad thermistor or bad vacuum will both stop the auger from working. Instead of hand feeding try pushing and holding the on button on some 4 button boards that will manually feed pellets, not a fix but easier then hand feeding through door. You can test if your on button will manual feed right now even when stove is running push, hold and auger should run constant until you let go.

 

[Iflyrctoo]

A bad thermistor or bad vacuum will both stop the auger from working. Instead of hand feeding try pushing and holding the on button on some 4 button boards that will manually feed pellets, not a fix but easier then hand feeding through door. You can test if your on button will manual feed right now even when stove is running push, hold and auger should run constant until you let go.

Never knew about holding the ON button to feed pellets. I tried it last night and that did in fact work. Thanks.
Right now all the lights indicate normal operation but of course it was already running and working fine.
Im going to pay close attention to the lights as soon as I do a startup after cleaning. I plan to also run the diagnostic check once again before startup, now with the new board installed as well. I want to see what temp the thermistors say at startup. I also dug out my infrared thermometer and will check them against that.

 

[Iflyrctoo]

A bad thermistor or bad vacuum will both stop the auger from working. Instead of hand feeding try pushing and holding the on button on some 4 button boards that will manually feed pellets, not a fix but easier then hand feeding through door. You can test if your on button will manual feed right now even when stove is running push, hold and auger should run constant until you let

Heres an update on my problem. I cleaned and restarted the unit again yesterday. I checked the thermistor readings from the test procedure against my infrared handheld thermometer while it was cold and they all seemed to agree within a couple degrees. Also rechecked them after everything warmed up and again they seemed to agree and were within reason. I watched every thing closely for about 45 minutes until I finally got it to the point of running correctly. I didnt notice any unusual flashing light indicators at any time that i could determine. The auger delay light would come on if you opened the hopper door but would go off when you closed it. That seems normal. However the auger would not initially run for over a half hour. You could during this time, manually run it by holding the on button in as stated before. What I noticed is that the auger came on and started working normally at the moment the second room fan kicked in. It seems to be working correctly since then. My understanding is the first room fan comes on when the flue reaches 200F and the second comes on when the plenum reaches 95. What could cause the auger not to come on until the second room fan does. Remember this is the second control board, the original and this brand new one. I did remove the whole side panel this summer and had to unplug everything to do so. Took pictures beforehand and am pretty sure I have everything hooked back the way it was. Ive been comparing it all to the vague wiring diagram that came with it and so far cant find anything hooked up wrong. Still I wonder what could cause this strange problem? What am I missing?

 

[ARC]

I am stumped. Does your agitator run for the first 45 minutes? For informational purposes after pushing on button there normally is a 3 minute delay before auger starts feeding. Wondering if your Neutral (white) wire is making contact or hooked up wrong from primary board to secondary board or from secondary board to auger. The Agitator, Auger and Hopper switch all run through the secondary board along with the second blower Hot (yellow) wire and the Plenum Thermistor. Just guessing now that maybe the neutral is not connecting until blower comes on. Make sure your white and yellow wires are not switched on secondary board also check the black and white wires between primary and secondary boards. See wire diagrams.

Secondary Board

 

[ARC]

On the next shutdown if wires are hooked up correctly also check that the exhaust thermistor is hooked to primary board and the plenum thermistor is hooked to secondary board. Then eliminate the hopper switch from the system by jumping the wires. Unplug stove at outlet, at the hopper switch unplug the purple and white wires. Attach these to wires together with a paper clip inserted into spades, tape connection, plug stove in and try to start. Sometimes when switches go bad they do weird things not just stop working. Remember jumping the switch is just for test purposes not a long term fix.

 

[ARC]

Maybe you have wires crossed , hooked to the forced air draft damper, if they were it would create just the symptoms you describe as the forced air draft damper spades only activate when plenum reaches 200 degrees.

 

[Iflyrctoo]

I appreciate all your help. Last night I sat and studied the wiring schematic and traced every wire in the blasted thing. At one point I thought I had found it. Looking at the picture in the schematic I thought the hot & neutral were reversed where the power cord plugs in. I had removed them this summer when I removed the side panels. The picture seems to be upside down and backwards the way I look at it anyway. However when testing for hot and neutral inside with a meter, the black wire is definitely hot and the white is the neutral. The jumpers between the two boards coincide as well with black being hot and white neutral. The two boards are even labeled hot & neutral at these connections and I confirmed them. I also checked the white and yellow wires and confirmed their connections as well. This really has me pulling my hair out.
I will try jumping the hopper switch. One time a few weeks ago I thought it was feeding pellets initially at startup until I opened the hopper lid and then closed it. Not 100% positive of this. However never have had it go out from opening it daily to fill the hopper. The auger delay light comes on when you open it and goes off when you close it. Maybe it barely makes contact and when the fan comes on it somehow shocks it into making better contact thus turning the auger on. At this point its got to be something really weird!
I also bought new thermistors for the exhaust & plenum. Might try those as well. I already confirmed those 2 connections but will again.
I removed the agitator years ago as it seemed to cause me more grief than good. Never have missed it. I just stir the pot once a day when i fill it.
Thanks again
Tim

 

[ARC]

If jumping the hopper switch and the new thermitors do not fix problem next step would be to run a neutral (white) wire from the primary circuit to the auger motor. From the first splice to the auger motor just need a length of wire and a female spade, and maybe even one to the hopper switch.

 

[Iflyrctoo]

If jumping the hopper switch and the new thermitors do not fix problem next step would be to run a neutral (white) wire from the primary circuit to the auger motor. From the first splice to the auger motor just need a length of wire and a female spade, and maybe even one to the hopper switch.

View attachment 307988

That sounds like a good idea.
The hopper switch will be easy to jump as there is a pair of connections midway between the switch and board (or wherever the white wire connects). They have alternate male/female plugs so I just have to unplug the switch and plug the two remaining terminals together.
Last night I experimented by unplugging room fan B (the one that triggered the auger to start working) and then opening and closing the hopper multiple times. While the auger would stop while the lid was open, it started again immediately every time I closed it. I thought it might not restart till I plugged the fan back in. Would have made more sense to me if it had.

 

[ARC]

I would also unplug the white plug(molex) from the main board check for bent pins or shorts, Red and Black are near each other red goes to auger and black goes to Right blower.

 

[ARC]

You could try setting the hopper switch and vacuum switch to ignore using the C codes Set C19 and C20 to 1

6220 C Code
To adjust the operation constant, press and hold the MODE and AUGER DELAY buttons
simultaneously for 3 seconds. The display will show “C-1”. Use the HEAT RANGE UP or HEAT
RANGE DOWN buttons to change the constant number (see the list of values below). When the
desired constant is displayed, press the ON button to toggle between viewing and editing the value.
While editing a parameter, use the AUX UP and AUX DOWN buttons to adjust the values to the
desired point, then press ON again to return to the constant number list. Press the OFF button to
exit the adjust operational constants mode.
 C-1- Reset to defaults (hold the MODE and AUGER DELAY buttons for 3 seconds to reset all
to defaults).

 C-19- Ignore Sense Errors (0-1)- When this parameter is set to 1, the sensor errors
including Interlock, and all fuse detection errors are disabled. The default is 0 (sense errors
enabled).
 C-20- Ignore Vacuum Switch (0-1)- When this parameter is set to 1, the vacuum switch is
ignored. The default is 0 (do not ignore the vacuum switch).

 

[Iflyrctoo]

You could try setting the hopper switch and vacuum switch to ignore using the C codes Set C19 and C20 to 1

6220 C Code
To adjust the operation constant, press and hold the MODE and AUGER DELAY buttons
simultaneously for 3 seconds. The display will show “C-1”. Use the HEAT RANGE UP or HEAT
RANGE DOWN buttons to change the constant number (see the list of values below). When the
desired constant is displayed, press the ON button to toggle between viewing and editing the value.
While editing a parameter, use the AUX UP and AUX DOWN buttons to adjust the values to the
desired point, then press ON again to return to the constant number list. Press the OFF button to
exit the adjust operational constants mode.
 C-1- Reset to defaults (hold the MODE and AUGER DELAY buttons for 3 seconds to reset all
to defaults).

 C-19- Ignore Sense Errors (0-1)- When this parameter is set to 1, the sensor errors
including Interlock, and all fuse detection errors are disabled. The default is 0 (sense errors
enabled).
 C-20- Ignore Vacuum Switch (0-1)- When this parameter is set to 1, the vacuum switch is
ignored. The default is 0 (do not ignore the vacuum switch).

I shut it down yesterday and thought for the day that I had it fixed. I switched out the thermistor on the exhaust fan outlet as I noticed that it wasnt reading nearly as high as my infrared thermometer did when hot. It seemed about right when cold however. I read in one manual that the one room fan supposedly comes on when that reaches 200F and that seems to be when the auger kicks in as well. With the new thermistor installed that fan and the auger both came on after about 5 minutes and all seemed OK then. The spot where the thermistor was, read about 205F with my handheld infrared when they clicked on. I thought I had it.
This morning I decided to shut down again just as a test to make sure all was fine. Nope, back to the drawing board. This time the auger came on for a few seconds at a time for 3 or 4 times right after I lit it and before either room fan came on. (thats how I remeber it working in the past) Then it stopped. I tried opening and closing the hopper lid and jumping the hopper switch. None of that made any difference. I had checked the molex plug, themistor plugs, cleaned all the connections with electronic cleaner and all looked OK. As long as the hopper lid was closed or jumped the auger would run if I held the ON button. I watched the temp on the thermistor location with the handheld thermometer and watched it pass 200F and top out around 240F to 260F varying as I hand fed the fire. Still the second fan and auger remained off.
Then suddenly the room fan came on with the auger and all is working OK at this point. It took about 25 minutes after lighting before that happened. I ran the test to see what the thermistors were reading at that point and that one said 264F. Way past the 200F mark. One of the other manuals I have says the room fan should come on at 150F. I notice some contradictions even within the same manual.
I havent tried the ignore codes yet nor have i run new white wires. Just dont have time today but not optomistic about that helping to be honest. This thing just has me baffled. I feel like its cursed.

 

[ARC]

With the new thermistor installed that fan and the auger both came on after about 5 minutes and all seemed OK then

I would go back and look at all the wiring again, almost seems like you might have wiggled something and made it work one time. Look for any pinched wires or bad connections. Look at main board where the white and black wires go to the secondary board those two wires are soldered on to the main board and can break off easily. I would try to unplug and reattach every spade or molex plug. What did you do with the two wires that use to go to the agitator?

 

[ARC]

Just a couple pics of control board

 

[Iflyrctoo]

Just a couple pics of control boardView attachment 308367View attachment 308366

Im assuming the white wire is the neutral throughout the wiring. Is this a safe assumption. If i run a new whie wire direct from the power supply plug that branches off to the following will I be safe. the draft fan, the right and left room fans, the auger, the auger safety switch

Just a couple pics of control boardView attachment 308367View attachment 308366

Can I safely assume the white wire is the neutral throughout this wiring? So if I ran a new white wire direct from the power supply plug branching off to the following would I be OK?
The draft fan, both room fans, the auger motor, the auger safety switch, the main circuit board at the molex plug, and the secondary side circuit board at the neutral terminal. Any of these I should avoid doing ?
I will have to look again to see what I did with the wires to the agitator. That was many years ago. I think I just unplugged them off the motor and taped them off but not sure off the top of my head. Thanks for staying with me on this. Its become a personal challenge at this point.

 

[ARC]

Can I safely assume the white wire is the neutral

That is correct white is neutral. The reason I suggest running a new neutral wire from the primary side to the auger is to by pass the neutral side from the secondary board and the secondary white neutral wire. If the auger works proper with the by passed neutral then you will know the problem is on the neutral side either the secondary board or the wiring is the problem. First inspect the wiring again from the secondary board to primary board and secondary board to motor and hopper switch wiggle wires and inspect for pinched wires. Also unplug both molex 4 wire plug from the secondary board and inspect pins then reattach.

 

[Iflyrctoo]

That is correct white is neutral. The reason I suggest running a new neutral wire from the primary side to the auger is to by pass the neutral side from the secondary board and the secondary white neutral wire. If the auger works proper with the by passed neutral then you will know the problem is on the neutral side either the secondary board or the wiring is the problem. First inspect the wiring again from the secondary board to primary board and secondary board to motor and hopper switch wiggle wires and inspect for pinched wires. Also unplug both molex 4 wire plug from the secondary board and inspect pins then reattach.

Ive checked all the plugs and pins multiple times and cleaned them with electronic cleaner as well. I will check them once more though. Ive also wiggled wires and connections lots of times but haven't seen that affect anything so far. The strange thing that sticks in my mind is when it eventually starts really working, it continues to do so till I shut it down again. I havent seen it quit feeding one time, once it eventually starts with the fan. Ive wiggled wires hoping I might see it quit intermittently once running but never have. I even unplugged the one room fan while running hoping to see the auger stop, but again no. Also played with the hopper switch but it also seems to operated correctly once running. Off when open and on when closed even when the fan was unplugged.
The manual states it should start feeding pellets after 3 minutes from startup. It doesnt mention anything about the room fan affecting it. And if memory serves me right, thats the way it always worked in the past. I could just light it and walk away. Usually it was feeding pellets before I left regardless if the room fans had come on yet or not. Yesterday it did start feeding like that for 30 seconds or so then stopped again until the room fan kicked in. And the fan didnt kick in at the appropriate temp either.
Unfortunately I dont think Ill have time to do anything with it tonight.

 

[ARC]

The important thing is to stay warm so no rush. This is not a fix but it might shorten the time until the auger starts, if you lower the temp in C15 to 70 or 75 then the second blower circuit will start sooner and the auger should start. If it doesn't work you can always go back to the 115 degrees.


6220 C Code
To adjust the operation constant, press and hold the MODE and AUGER DELAY buttons
simultaneously for 3 seconds. The display will show “C-1”. Use the HEAT RANGE UP or HEAT
RANGE DOWN buttons to change the constant number (see the list of values below). When the
desired constant is displayed, press the ON button to toggle between viewing and editing the value.
While editing a parameter, use the AUX UP and AUX DOWN buttons to adjust the values to the
desired point, then press ON again to return to the constant number list. Press the OFF button to
exit the adjust operational constants mode.
C-15-Low Temp Vent Setpoint-(70-200)- This variable is used to control the vent controlled
room fan. If the measured vent temperature is greater than the Low Temp Vent Setpoint,
the vent controlled room fan will turn on. If the Measured vent temperature is less than the
Low Temp Vent Setpoint-5, the vent controlled room fan will turn off. The default for this
setpoint is 115°F.

 

[ARC]

I ran the test to see what the thermistors were reading at that point and that one said 264F.

Not sure if the number means anything as the test is programed to run in a cold/cool stove not a hot stove.

 

[Iflyrctoo]

The important thing is to stay warm so no rush. This is not a fix but it might shorten the time until the auger starts, if you lower the temp in C15 to 70 or 75 then the second blower circuit will start sooner and the auger should start. If it doesn't work you can always go back to the 115 degrees.


6220 C Code
To adjust the operation constant, press and hold the MODE and AUGER DELAY buttons
simultaneously for 3 seconds. The display will show “C-1”. Use the HEAT RANGE UP or HEAT
RANGE DOWN buttons to change the constant number (see the list of values below). When the
desired constant is displayed, press the ON button to toggle between viewing and editing the value.
While editing a parameter, use the AUX UP and AUX DOWN buttons to adjust the values to the
desired point, then press ON again to return to the constant number list. Press the OFF button to
exit the adjust operational constants mode.
C-15-Low Temp Vent Setpoint-(70-200)- This variable is used to control the vent controlled
room fan. If the measured vent temperature is greater than the Low Temp Vent Setpoint,
the vent controlled room fan will turn on. If the Measured vent temperature is less than the
Low Temp Vent Setpoint-5, the vent controlled room fan will turn off. The default for this
setpoint is 115°F.

Heres another contradiction example I dont understand. The manual that came with the furnace says the room fan will come on when the flue thermistor reaches 200F. C-code 15 suggests the default is 115 F and adjustable range is 70F - 200F. Another manual I have for it says the room fan will come on when flue reaches 150F. In reality on Monday that room fan didnt come on until 260F had been reached for several minutes. On Sunday it came on right about 200F. Its hard to diagnose when there is so much contradicting info out there.

 

[ARC]

C15 controls the furnace vent fan not the room fan, should be on when plenum thermistor is at 115. I am assuming this is the fan that comes on when the auger starts working is that correct? The room fan is the one that comes out the front of the stove it should come on when the exhaust blower thremistor reaches 150 degrees. Which fan comes on when the auger starts working?