Accentra FS combustion blower not shutting down?

[womaus]

Greetings,

Finally got the stove installed, vented, OAKed, a few test burns. Let the City Code Department know it's ready for inspection.

I'll get some pics and some more details on the installation soon, need to get some pics optimized etc.

I've got one (possibly two) issues right now though:

It's a 2004 Harman Accentra FS, purchased as used. Fully cleaned, lubed up, blown out with compressed air while outside (was careful of the vacuum switch), then tested outside with a half hopper of older pellets that same afternoon. Upon plugging in the stove at that time the glass 5A fuse blew (made me jump a bit...quite the flash). Replaced the fuse, stove started without issue. That was a few weeks ago.

Yesterday afternoon, after getting the exhaust vent fully configured and tightened up I did the initial test burn. Everything appeared to go as expected. After the fire got up and going for 10 minutes or so, everything running fine, the stove shut down completely. No lights on the swing out control panel (fully opened on the hinge). Figuring it was the fuse again I started to close the panel door...the stove kicked back on. A few minutes later it dies again, no lights. Move the door a bit, lights back on, blowers start up, all good. Another few minutes it dies, no lights. I found if I closed the control panel door fully it would stay on without issue. Will need to track down the short / loose connection.

I let it burn for a good 4 hours or so, on low settings. No problems with smoke leaks, and getting decent heat production even on the low settings. I then shut the stove down using the Stove Temp / Room Temp potentiometer, closely watched for 20 minutes or so to ensure that the fire died out. Happy with the situation I went on to other things, eventually retiring for the evening.

At 5AM I awake due to the cat sleeping on my head, wanting food. Went downstairs and found the combustion fan running, with the stove stone cold (outside temp stone cold). No other obvious issues. Opened the front access door, fan continues to run. Eventually unplugged from the APC UPS to stop the fan.

Back to the stove by 9AM, ran another quick test burn. This time no issues with the stove continuing to operate no matter which position the control panel is, opened or closed (still need to trace the wiring to kill that gremlin). Burned for an hour or so, shut it down manually using the Stove Temp / Room Temp "Off" setting. An hour later the stove is cold, but the combustion fan is still running. Again unplugged from the UPS.

During the full cleaning I did a reseat of all connections, cleaned the ESP with an alcohol wipe, greased what was needed.

I was able to find this other thread that detailed a like issue:

https://www.hearth.com/talk/threads...-blower-not-shutting-off.148691/#post-2007345

Looks like his fix was a new board.

Any ideas from the experts? What should I be looking at to verify the cause?

Otherwise I'm somewhat happy with everything, I hope the inspector is also on Monday.

Many thanks in advance for your time reading what was going to be a short concise post...

 

[womaus]

More searching on the site I have now found this from back in 2011:

These Accentras are a strange beast sometimes....let it run out of pellets, cool down, and if it doesn't shut down, unplug the stove for about one minute. Put the on/off knob in off and plug it back in. This will give it a "hard" reset. Do that and let us know what happens. While it's off give it a serious cleaning. Keep checking in, we want to help.

https://www.hearth.com/talk/threads/harman-accentra-will-not-turn-off.79540/

I'll give this a try tonight, certainly can't hurt anything?

 

[Mt Bob]

You can try unplugging,cannot hurt.But what should have been done is find out why fuse blew before running stove,and the problem at control door.You may have already damaged the board.

 

[womaus]

You can try unplugging,cannot hurt.But what should have been done is find out why fuse blew before running stove,and the problem at control door.You may have already damaged the board.

Yeah, I had that same fear when the fuse blew a few weeks ago. I did find back then a single wire in the bundle that was a bit wedged in the hinge area. Not cut through the insulation, but kinked.

I'm waiting now for the stove to completely consume what I left in the hopper, then will try the hard reset. May or may not relook at the wiring situation after the shutdown...might wait until I see if the hard reset actually fixes the issue. That way I can see what actually fixes the issue.

It's odd today that the stove isn't shutting itself off abruptly today as it was yesterday. No issues with moving the control panel.

 

[womaus]

Your signature shows a "96 Accentra"? Seriously? What is the serial #?

 

[Mt Bob]

Your signature shows a "96 Accentra"? Seriously? What is the serial #?

used to be 06?maybe when they redid things?will try to fix

 

[Mt Bob]

For "hard reset" stove only has to be off.Just unplug stove,run a screwdriver(or whatever) across plug terminals,touching both at same time.This will dump any residual charge in the capacitors.Turn stove knob off,plug stove back in.For that fuse to blow,has to be something bare somewhere.If it was a hard failure stove would not run.Also very easy to remove control board and check wires on back,just 2 screws.

 

[womaus]

For "hard reset" stove only has to be off.Just unplug stove,run a screwdriver(or whatever) across plug terminals,touching both at same time.This will dump any residual charge in the capacitors.Turn stove knob off,plug stove back in.For that fuse to blow,has to be something bare somewhere.If it was a hard failure stove would not run.Also very easy to remove control board and check wires on back,just 2 screws.

Stove cooled down to room temperature (the constant fresh air from outside due to the problem with the combustion fan no doubt helped).

Unplugged the stove, crossed the plug tips with a screwdriver, multiple times to be sure.

Did a quick clean on the stove, pulling the interior baffles and cover on the combustion fan. Vac'd all areas, though they really did not need any attention, less than a half bag of pellets burnt since the full clean. All looked good.

Quick vacuum of the hopper area. For good measure grabbed some wax paper from the kitchen and slicked down the hopper interior.

Against my previous thoughts I pulled the control board, took a look at the wiring harness. #6 wire (white) that the wiring diagram in the manual shows to feed the combustion motor was the one that had a slight nick / crimp. Slipped some electrical tape around the problem area for good measure. It did not look to be cut through in any way. All other wires in the harness look to be in good shape.

Replaced the existing 5A fuse with a fresh one. Tightened up the connectors for the fuse also.

The dip switches are all set to "Off", 1 - 8. I pushed all to "On" then back to "Off" a few times to clean the contacts.

Looking again at the Accentra Wiring Diagram in the original manual I see that there is a jumper (J2) on the control board that shows to be jumped from the factory specs. I believe this is for modification with use of a remote thermostat? I do not remember seeing a jumper on there, it looked to be open. If not jumped could this be causing the problem? I'll need to pull the board again to be sure.

Filled the hopper with approximately 10# of TSC white bag / blue lettering hardwood pellets I purchased earlier today. Previously I had been firing a bag of Pennington Hardwood Blend from Walmart.

Set the control panel as it should for "Off". Plugged back into the UPS. Combustion fan immediately comes on with stove set to "Off. No luck there for the fix.

Stove starts up as it should, no issues there. Using the same settings as earlier I'm getting much better heat performance from the stove, most likely from the change of pellet brand.

I'll burn up these 10# of TSC, then take a look at the board again. If there are any other ideas out there for this issue I will most appreciate the input.

 

[Mt Bob]

The switches will not affect blower.Newer boards do not have the jumper spot,not for t stat,harmans not set up for t stat BUT one can be added.Would really inspect wiring harness before installing new board.One problem area is the wires that go from board to combustion blower.Also where wires move in back of stove,when opening/closing control panel.I leave mine open all the time,esp in this in between weather,switching from room to fireplace mode.Good price for board on ebay right now--190.

 

[womaus]

The switches will not affect blower.Newer boards do not have the jumper spot,not for t stat,harmans not set up for t stat BUT one can be added.Would really inspect wiring harness before installing new board.One problem area is the wires that go from board to combustion blower.Also where wires move in back of stove,when opening/closing control panel.I leave mine open all the time,esp in this in between weather,switching from room to fireplace mode.Good price for board on ebay right now--190.

You are certainly correct about the J2 and the dip switches...this forum has some impressive denizens. Good knowledge to be had.

Here's a pic of my board...is the one advertised on eBAY the correct item? I'm not adverse to spending a bit more through Amazon etc if needed.

I do have an inquiry out to Brunner's Bits and Pieces to see if they think my board is a candidate for repair.

Another thought on the purchase of a new board, will a Harman certified tech need to calibrate it?

 

[womaus]

Another quick question:

The original stove manual shows the glass fuse to be a 5A...looking at Harman Accentra parts on the web all I'm seeing are fuses of 6A recommended. Is it better to go with the 6A?

 

[Mt Bob]

There are (i think) only 2 possible harman boards(other than the p38 upgrade) one for most stoves and one for the furnaces.Newest part number,to fit your stove,is 1-00-05886.If you have any doubt, just call mountainview (or other dealer)and tell them what you need,pay the xtra money for part,but will give you an inside line for helpful info.If you are not a tech the extra money paid is well worth it.Harmans have no external programming,it is done with the installed chip,and the dip switches.Actually very similar to the old austroflamms where just make it work for 90% of buyers.Newer high quality stoves are different.Also 200 dollars for a board is dirt cheap,go buy a new tire for your truck,or price quadrafire controlers.Also ignore the fuse difference,being old style,the fuse is to protect from burning your house down,not protect your item.

 

[womaus]

There are (i think) only 2 possible harman boards(other than the p38 upgrade) one for most stoves and one for the furnaces.Newest part number,to fit your stove,is 1-00-05886.If you have any doubt, just call mountainview (or other dealer)and tell them what you need,pay the xtra money for part,but will give you an inside line for helpful info.If you are not a tech the extra money paid is well worth it.Harmans have no external programming,it is done with the installed chip,and the dip switches.Actually very similar to the old austroflamms where just make it work for 90% of buyers.Newer high quality stoves are different.

I'll get in touch with Mountainview tomorrow...get the board ordered. I'd like to get this problem behind me, not have to worry about the operation of the stove.

Also 200 dollars for a board is dirt cheap,go buy a new tire for your truck,or price quadrafire controlers.Also ignore the fuse difference,being old style,the fuse is to protect from burning your house down,not protect your item.

New tire for my truck? You must have me confused with someone else. I drive a Fiat Abarth. It's my third mid-life crisis rearing it's ugly head. Put three bags of pellets into the back end yesterday, screwed up the steering geometry fiercely.

i agree with the fact that the $200 is cheap, again, I'd like to get past this quick.

 

[womaus]

Pushed an inquiry out to one of the stove part suppliers, they came back with this:

I talked to our techs and they feel that the two most likely problems are the esp or the board. They both suggested changing your esp first and it is going to be the cheapest fix. Just make sure you purchase the same color esp as you have now. You could purchase both the esp and board so you have both just in case and as long as you do not open or install the board you can return it for a refund if the esp turns out to be the problem. Please let me know any other questions or concerns.

Seems like a reasonable way to go forward?

And in the ongoing troubleshooting, last night during another attempted shutdown both the combustion and distribution fans stayed on well past the time needed.

I'll need to pull the stove away from the wall, get the OAK pulled off back of the unit, it's unfortunately in the way of removing and replacing the ESP. Not fun moving 400lbs of dead weight.

EDIT: Called one of the local Harman dealers, the thermistor is in stock at $65. Road trip!

 

[Lake Girl]

The advice you have received is sound. Worst case if you buy the ESP and it does not correct the problem, put the old one on the spare parts shelf

 

[womaus]

The advice you have received is sound. Worst case if you buy the ESP and it does not correct the problem, put the old one on the spare parts shelf

Well...

Picked up the new thermistor, pulled the stove away from the wall (needing to break all of the sealed vent connections). Pulled out the old with all of the connected wiring, installed the new.

Vents connected back up, ready to go. More pellets in the hopper. Set as "Off", plugged it in. "Power" diode comes on, and a single blink on "Status". As does the combustion fan (just as before). Set for 70 degrees, auger at 3, then to Room Setting.

Nothing, except for 4 blinks off the Status diode.

My oh my.

My wife has started pointing at me and laughing.

 

[womaus]

I'm an idiot.

If I was less of a man I'd immediately edit and delete the above post...hide the evidence.

Yep. Connected the Room Sensor. 4 blinks go away.

Still an issue with convection blower though

 

[womaus]

The smell of heat is sweet....

New control board at $190.00 seems to have fixed the issue. Getting the first test fire going now.

If so, I'm buying the first three rounds of drinks to all that will meet up at some dive midway between us all...

Let's see if my wife points and laughs now?

 

[alternativeheat]

The smell of heat is sweet....

New control board at $190.00 seems to have fixed the issue. Getting the first test fire going now.

If so, I'm buying the first three rounds of drinks to all that will meet up at some dive midway between us all...

Let's see if my wife points and laughs now?

Yay ! Congrats.

 

[Lake Girl]

Hope you kept the old board and will be sending it out for repair ... JIC!

 

[Mt Bob]

Really nobody out there that repairs the newer boards,other than replace the pots.With the expense of setting up to do the programming and smt just not worth it.

 

[womaus]

Really nobody out there that repairs the newer boards,other than replace the pots.With the expense of setting up to do the programming and smt just not worth it.

I had a long conversation with the tech at the Harmon dealer I purchased the goods from. He too stated that even Harmon doesn't want to see the old boards. With other topics that came up I believe I have found a dealer I can trust for future needs.

And yeah, so far the stove is doing what it should do. Overall better performance. I'll know by Sunday, after a few ups and downs of the system if it is truly fixed.

I will say I've learned quite a bit about this stove due to the problems. Should make future maintenance and repairs easy.

Again, thanks to all for supporting the fool that bought a used Accentra. (I've already started on my share of the beers, if nobody shows up soon I'll start on those too).

 

[Mt Bob]

I bought mine to resell,as that is what i do part time,but i am getting old,decided to keep this one and put it in living room.Last winter was the most comfortable ever having this upstairs.I mainly kept it for 2 things-auto start and the looks.BUT to warn you,the output of the stove is not as advertised.OK for me,I have a small cabin,but will not even come close to what my old integra will do.@ things,as yours is older,if it develops gummy stove syndrom,you can do the 2 previous dealer fixes,no need to replace feeder unit.Check your gears on auger and auger motor,make sure they are the same size(diameter)as may have not had the upgrade.You will love cleaning this stove,takes one beer.The easy and long time between cleanings makes up for lower heat output.

 

[womaus]

I bought mine to resell,as that is what i do part time,but i am getting old,decided to keep this one and put it in living room.Last winter was the most comfortable ever having this upstairs.I mainly kept it for 2 things-auto start and the looks.BUT to warn you,the output of the stove is not as advertised.OK for me,I have a small cabin,but will not even come close to what my old integra will do.@ things,as yours is older,if it develops gummy stove syndrom,you can do the 2 previous dealer fixes,no need to replace feeder unit.Check your gears on auger and auger motor,make sure they are the same size(diameter)as may have not had the upgrade.You will love cleaning this stove,takes one beer.The easy and long time between cleanings makes up for lower heat output.

I decided on the Accentra to be able to get it into my living area, the wife would not be happy with a "lump" in the area. That a good friend of mine has had one running since 2006 without issues pushed me further.

I can see what you are saying about the output...it will certainly be sufficient for what I plan on using it for but I've seen better performance with other stoves. We're looking to shut down parts of the house and just heat a few rooms for the majority of the day. Still happy due to the appearance and what I hope to be the stability.

Gummy stove syndrome? Tell me more...I'm new here. Somewhat virginistic. Dealer fixes? Huh?

And a one beer cleaning? Why did I not know this? I was looking for a three to twelve beer cleaning routine...

 

[womaus]

Ahhh...just found this. Should take up my whole evening.

https://www.hearth.com/talk/threads/harman-accentra-gummy-stove-syndrome-solution.45548/