Accentra shuts off & never re-starts

[smirnov3]

Howdy. I think I've gotten my Accentra mostly figured out, but one recurring problem is that when I lower the set temperature too far, the stove shuts off & never re-starts.

What happens is that we have the stove set to 70 for over night, but during the day (when everybody is downstairs), we want to turn it down to 65.

If you crank it down in 2-3 steps over the course of an hour (so that the fire never goes out), it works fine.

BUT, if you just turn it all the way from 70 to 65, the stove shuts off (like it should) and never re-starts when temperature reaches 65. You have to shoot it up to 67 until it lights, then crank it back to 65 to get it going again.

What's going on?

 

[HarryBack]

my 2 cents....guessing a bad potentiometer on the temp dial of the circuitboard, OR a poorly functioning room sensing probe (either a bad crimped connection, or not plugged in well, usually). Have the dealer plug their DDM into the stove and see what the room temperature probe is actually reading versus the setting on the dial, and note the room temp as well, for the heck of it. The DDM will tell you the actual temp that the room sensing probe "sees", and you can compare it with the dial setting....possibly yours is 2 degrees off. Oh, yea, and eat some peanut butter.

 

[Histosteve]

My Accentra works the same way. I set my stove at 70 during the day and 65 at night. As soon as I dial it down, it goes through the motions of shutting down. It stays off until it gets around 62 to 63 then it starts. Then it maintains the living area at the 65 degree mark.

 

[smirnov3]

The problem is that mine stays off even when the temp hits 60 (according to a digital thermometer that correlates pretty well with the Accentra's settings)

It controlls pretty well the rest of the time, though.

 

[Papaw]

Howdy. I think I've gotten my Accentra mostly figured out, but one recurring problem is that when I lower the set temperature too far, the stove shuts off & never re-starts.

What happens is that we have the stove set to 70 for over night, but during the day (when everybody is downstairs), we want to turn it down to 65.

If you crank it down in 2-3 steps over the course of an hour (so that the fire never goes out), it works fine.

BUT, if you just turn it all the way from 70 to 65, the stove shuts off (like it should) and never re-starts when temperature reaches 65. You have to shoot it up to 67 until it lights, then crank it back to 65 to get it going again.

What's going on?

My Accentra insert return air thermistor has a differential of eight degrees. If the room temperature is set to 70 it won't come back on till after 62 degrees, much too long of a time. Is this adjustable? Or is this normal? I don't even run it in roome temperature mode anymore. No help from the dealer. Other problems with this unit too. Incomplete burn. I have used one ton of pellets in this new stove. It's been thoroughly cleaned twice. The ash pan has been emptied four times. It needs emptying again. The store personell didn't know how to use a draft gauge. It is a requirement for installation. Consequently it is set to minimum due to high line voltage (122v).
This stove was stored outside in the packing crate for many months before I picked it up. I had to deliver it myself. Should have suspected something by this. I feel that moisture affected the phenolic of the control board causing it not perform as expected. Evidenced by rusty spots inside of the unit.
The dealer states that Harmon won't replace the control board untill it's a least 5 years old??? His solution is to take the stove back. Which is ok with me but I will be left with a $400.00 hole in my house.
So far this season temps have been mild. One night it went down to 12 degrees I had all I could do to get it to 58 degrees in this 1200 square foot space.
Premium pellets used. $199.99 a ton plus tax. At Southern States.

Thanks for any comments on this unusual experience.
Papaw

 

[stoveguy2esw]

peanut butter??????????????????

 

[HarryBack]

Papaw:

Where are you determining temperature differential? The only valid place to do this would be where the end of the room sensing probe is, and with a thermometer you know is accurate. There shouldnt be an 8 degree differential. If the dealer has a DDM, he can plug it into the board and see what the room sensing probe actually reads and is sending as a signal to the control board.
I also dont think its good practice to willy-nilly set the combustion fan voltage without metering the draft as well. Draft and line voltage are two very different animals. If your draft is poor in the first place, and youd never know without a test, you are only making the matter worse by setting the combustion fan low.
If the stove sits for any amount of time, parts may rust, particularly the interior, "some spots of rust" dont worry me in the least. I also dont think the moisture could be great enough to affect the board, unless it was in direct contact with water, rather than the humidity.
The dealer stating that Harman wont replace the control board until its 5 years old is just purely incorrect. If the board is defective, Harman WILL replace it, up until 3 years old, when the electrical warrantee expires. Wait over that, and you'll be buying a new board.
Dont understand the $400.00 hole comment...its an insert...fits in a fireplace. The stove should put out more heat than it seems to, as long as your house is reasonably well insulated. The place to start is the draft reading. Then, Id make sure the heat exchangers are clean, and oh, yea, check the board and probe with the DDM.

 

[Papaw]

Thanks for your reply.
"Where are you determining temperature differential? The only valid place
to do this would be where the end of the room sensing probe is, and with a
thermometer you know is accurate. There shouldnt be an 8 degree
differential. If the dealer has a DDM, he can plug it into the board and see
what the room sensing probe actually reads and is sending as a signal to the
control board."

I am placing a test thermometer under the ash lip in the area of the thermistor. The kind that would clip onto your shirt pocket A Nesco thermometer. The two times the store rep came here he used the DDM. The first time to set the draft??? The second time to report that the combustion motor was receiving 120 volts.

" I also dont think its good practice to willy-nilly set the combustion fan
voltage without metering the draft as well. Draft and line voltage are two
very different animals. If your draft is poor in the first place, and youd
never know without a test, you are only making the matter worse by setting
the combustion fan low."

On page 19 of the Harman Accentra Pellet Insert manual on the left side of the page last two paragraphs where it has the wod required it shows a definite relationship between draft and voltage. Indicating less draft with higher voltage. IMO.
I have tried different settings on that control to no avail. The person that was here looked at the draft test adaptor and said hmmm.
The setup here is straight out the wall to a clean-out T then vertical three feet to a dryer vent style cap.
On the second visit the store rep set the draft with the meter reading half, at rest. I asked isn't there a zero adjust on that meter? He replied no. So my draft has never been really set to anything. The ash is grey and in the shape of pellets.
I have cleaned this unit according to directions two times. What I am finding is the result of whatever is wrong with this unit. Not finding the cause.

"If the stove sits for any amount of time, parts may rust, particularly
the interior, "some spots of rust" dont worry me in the least. I also dont
think the moisture could be great enough to affect the board, unless it was
in direct contact with water, rather than the humidity."

This was only a guess on my part trying to find a cause for the poor operation of this unit.

"The dealer stating that Harman wont replace the control board until its 5
years old is just purely incorrect. If the board is defective, Harman WILL
replace it, up until 3 years old, when the electrical warrantee expires.
Wait over that, and you'll be buying a new board."

You and I both know this is true. I have to make the assumption the dealer is untrained in Harmon's business practices and the basic operation of the product. I am not suppose to be troubleshooting this defect. This was brand new out of the crate with these problems. I was left with a bag of bolts and parts. I had to install the return air thermistor. The fiberglass protector of the flue pipe was in the trash.

"Dont understand the $400.00 hole comment...its an insert...fits in a
fireplace. The stove should put out more heat than it seems to, as long as
your house is reasonably well insulated. The place to start is the draft
reading. Then, Id make sure the heat exchangers are clean, and oh, yea,
check the board and probe with the DDM."

The $400.00 hole refers to what I will be left with when they remove the stove simply because they don't know what is wrong with it. The stove is placed in a wooden fireplace enclosure. (fake fireplace) straight out through the wall. With a 4" pipe through a thimble.
I have cleaned out the heat exchanger and the two tubes with the wire brush.
This house was finished a year ago with very good insulation job done. I have opened a window on each side of the stove in case it is poor combustion air to no improvement.
I think if the fix mentioned above in another post was done here I would be ok. Control board and combustion fan. Or the relationship between the auger and the board. Seems like a timing problem to me.
Harmans position seems to be contact the dealer. The dealer and myself are tired of fooling with this. I asked if a tech from Harman would come here. I'm not that far from PA. The answer was no.
Seems like it is a shame to me if that is the only solution. (To remove it) I bought this because it was supposed to be the Cadillac of stoves.

Thanks for your knowledgable reply,

Papaw
PS: The medalion picture is after two weeks of use. Click on it to see. The hopper door is open to enhance the view of the fire.

 

[HarryBack]

Put the room sensor low and away from the stove, with the thermometer next to it. The "ash lip" is ont he front of the unit, just below the door, and other than the top of the unit, the worst place for the probe to be.

You dont set the draft with the DDM at all, you'd need a draft guage, or magnahelic to do so. And yes, they do "zero", at least all the ones Im familiar with.

As to your draft, you can AFFECT your draft with the pot setting, but since you dont know what your initial draft IS, how can you set it at all?

Are you bringing in outside air as well? Might be another thing to try, especially since you dont seem to be getting complete combustion. Did the dealer do the install, or you?

Draft reading would be ideal here.

When cleaning the exchangers, you did remove the baffle plates, right?

Sounds like incomplete combustion to me, but quite difficult to diagnose online without knowing all the stove settings and readings. What are the dial settings as well?

 

[Papaw]

Put the room sensor low and away from the stove, with the thermometer next to it. The "ash lip" is ont he front of the unit, just below the door, and other than the top of the unit, the worst place for the probe to be.

You dont set the draft with the DDM at all, you'd need a draft guage, or magnahelic to do so. And yes, they do "zero", at least all the ones Im familiar with.

As to your draft, you can AFFECT your draft with the pot setting, but since you dont know what your initial draft IS, how can you set it at all?

Are you bringing in outside air as well? Might be another thing to try, especially since you dont seem to be getting complete combustion. Did the dealer do the install, or you?

Draft reading would be ideal here.

When cleaning the exchangers, you did remove the baffle plates, right?

Sounds like incomplete combustion to me, but quite difficult to diagnose online without knowing all the stove settings and readings. What are the dial settings as well?

Harry, On page 13 of the installation manual is a very clear picture of the placement of the return air sensor. Which sounds to me like an appropriate place to put it.

About the draft, I am dealing with folks that appear to never have set the draft on one of these.

The install was done by an outside contractor that has a working relationship with the store. However they are primarily carpenters. The ones that finished this house.

Yes I removed the baffle plates and run the wire brush up the two tubes. The space under the firepot was half full of ash at the two square holes at the back. But all this is not what's wrong it is a result of what's wrong.
The exaust pipe was sealed with the caulk provided by the dealer. Double walled 4".
I'm sure it's the control board and possibly the speed of the combustion fan. It appears to me that all these fans have to syncronized properly. In addition to the all important draft setting.
They will probably remove this stove this week. I have been adjusting and cleaning for two months. So whatever is wrong with it is a mute question. I will stuff a pillow in the hole for the thimble and hope it doesn't rain till I get to a not that far QuadraFire Mt Vernon AE Dealer.

Thanks for your help.
Tom

 

[HarryBack]

good luck, Tom.

 

[GVA]

Wow, The dealer Needs to use the rest of the tools in the toolbox on this one.
Voltage does affect draft but 122v isn't enough.
Piping also affects draft. Are you saying that you go straight out and thats it with 4" pipe?
I have 125v at my stove... and my draft I have set with a magnehelic not my volt meter.
Here's what i'm getting at I could jam a ball of tinfoil into my pipe and yes the blower is still reading 125volts but the draft is no longer on the negative side.
Back to the other thing place the probe in different locations make sure it's crimped to the stak-ons good and the insulation isn't pinched or dammaged.

 

[Papaw]

Wow, The dealer Needs to use the rest of the tools in the toolbox on this one.
Voltage does affect draft but 122v isn't enough.
Piping also affects draft. Are you saying that you go straight out and thats it with 4" pipe?
I have 125v at my stove... and my draft I have set with a magnehelic not my volt meter.
Here's what i'm getting at I could jam a ball of tinfoil into my pipe and yes the blower is still reading 125volts but the draft is no longer on the negative side.
Back to the other thing place the probe in different locations make sure it's crimped to the stak-ons good and the insulation isn't pinched or dammaged.

I might say they haven't even opened the tool box.
I don't use my volt meter to check draft. I used it to check line voltage as stated above. My draft has never been set as stated above. At your 125v line voltage where is the potentiometer as if you were looking at a clock?
The piping is straght out to a cleanout T then verticle for three feet terminating in a drier type vent cap. As stated above.
Additional info, it runs best at a setting of two for the pellet feed but I was cautioned that it wouldn't run hot enough at that setting. Anything higher that 2 builds up an inch and a half of unburnt pellets. And then I have to scrape the fire pot every four hours. Then it runs good till the next scrape out.
Not my choice but they should be picking this stove up this week.

 

[GVA]

Wow, The dealer Needs to use the rest of the tools in the toolbox on this one.
Voltage does affect draft but 122v isn't enough.
Piping also affects draft. Are you saying that you go straight out and thats it with 4" pipe?
I have 125v at my stove... and my draft I have set with a magnehelic not my volt meter.
Here's what i'm getting at I could jam a ball of tinfoil into my pipe and yes the blower is still reading 125volts but the draft is no longer on the negative side.
Back to the other thing place the probe in different locations make sure it's crimped to the stak-ons good and the insulation isn't pinched or dammaged.

I might say they haven't even opened the tool box.
I don't use my volt meter to check draft. I used it to check line voltage as stated above. My draft has never been set as stated above. At your 125v line voltage where is the potentiometer as if you were looking at a clock?
The piping is straght out to a cleanout T then verticle for three feet terminating in a drier type vent cap. As stated above.
Additional info, it runs best at a setting of two for the pellet feed but I was cautioned that it wouldn't run hot enough at that setting. Anything higher that 2 builds up an inch and a half of unburnt pellets. And then I have to scrape the fire pot every four hours. Then it runs good till the next scrape out.
Not my choice but they should be picking this stove up this week.

One check this out
http://www.harmanstoves.com/maintenance/accentrainsertcleaninginstructions.pdf
Two rereading the post you are in stove mode correct? This may cause the unburnt pellets. at higher feed rates.
Three By scrape out the burn pot do you mean the hard carbon buildup (clinkers) or the loose ash?
As far as the posistion of the potentiometer it doesn't really matter because it depends on the venting etc. but let's just say it is set in the center.
What pellets do you burn?
how many pellets in a day?
it's pretty warm around and the stove runs dirtier than when in the dead of winter.

As far as the magnehelic the needle also moves if it is not held level after being zeroed.

 

[Papaw]

One check this out
http://www.harmanstoves.com/maintenance/accentrainsertcleaninginstructions.
pdf
I have that PDF file and have used it in my many cleanings of this unit. What develops is a symptom not the cause. This stove acted this way right out of the crate..
Two rereading the post you are in stove mode correct? This may cause the
unburnt pellets. at higher feed rates.
I have tried all different feed rates. It seems to burn cleaner at a setting of two.
Three By scrape out the burn pot do you mean the hard carbon buildup
(clinkers) or the loose ash?
I keep a hammer and a one inch chisel on my dining room table to clean off the unburnt fuel from the burn pot every four hours.
As far as the posistion of the potentiometer it doesn't really matter
because it depends on the venting etc. but let's just say it is set in the
center.
Thanks.
What pellets do you burn?
how many pellets in a day?
I get my pellets from Southern States a farm store. $199.99 a ton. I pick them up. Premium grade.
I use maybe a bag or a bag and a half during colder spells.
it's pretty warm around and the stove runs dirtier than when in the dead of
winter.
The night it went to 12 degrees I could only get it up to 58 in this 1200 square foot space.

As far as the magnehelic the needle also moves if it is not held level after
being zeroed.
They didn't know how to zero the meter.
The fire is just not burning hot enough to consume the fuel. In a demo stove the ash buildup was nill and the fire was active and came to a point. This gets lazy after a period of time. After chipping out the baked on unburt fuel the fire looks good.

 

[Papaw]

I think Elk has nailed it down from another post. The way everything else was done here. I wouldn't be surprised if the smoke pipe wasn't sealed properly thereby loosing draft. Affecting the intensity of the burn. I provided the high temp silicone caulk. The expensive tube of that material wasn't anywhere to be found at th end of the installation. I'm not sure it was even used.

 

[HarryBack]

I seriously doubt your problem stems from "leaky" pipe syndrome. Leaks in a short run such as yours just dont affect draft to any great degree. Unfortunately, your dealer didnt take readings, and doesnt seem to have a DDM, so our two best diagnostic tools are not available to us here. I still havent seen what settings the stove runs on yet. As for the manual you put so much stead in...its GREAT that you read the manual, too few do. But, there is much to learn from actually running the units, fixing problems, and installing them that ISNT in the manual. GVA and I are only trying to help you and attempting to pick up where your dealer seems to have failed so miserably. Myself, Ive only sold quite literally hundreds of the units you speak of, and GVA is one of the most technical non-dealers who posts in this forum. We are kind of at a loss as to diagnosing these problems without proper info. I think your dealer should get off his duff and learn to do his job.

 

[Papaw]

Harry,
I'm grabbing at straws here. I've been looking for a solution for two months now. They do have a DDM. They proudly trotted it out on the first visit to set the draft, as per my request, referring to the manual instructions. Even I know you can't set the draft with the DDM
I have tried many setting. At present for the last several hours the feed rate is at 2, the distribution blower on high, the temperature on 75 and the switch on auto. 38 degrees out and 69 in. Well insulated one year old structure total 1200 square feet. The ash is gray. The flame is lazy, blue to white to yellow. I vaccumed out under the fire pot yesterday. All I have to do is use the tool provided and scape off the ashes and use it on the inside of the fire pot and it will be good to go for the next four hours or so.
A few years ago before they improved these units I had a Whitfield in another state with no problems.
I refer to the manual because that's all I have except for this forum. When someone tells me something contray to what's in the manual I have to mention what I have read in the manual. I'm sure Harman has a R&D department.
The dealer gave me four bags of his brand pellets to try. No improvement.
If I would know where, I would buy a WC gauge myself. I know you guys are trying to help and I certainly do appreciate it. I live alone and my cope is running over with this.
In addition to the defective room sensing thermistor the basic complaint is to keep it running half way decent, is to chisel out the unburnt fuel from the fire pot approximately every four hours.
The dealer gave up and his solution is to take the stove back. I'm sure there will be somebody higher up in the pecking order to ask WHY?
In all the units you have sold is there a common thread here? I mean is there a large turnover in control boards or something else?
Thanks for your help, Tom

 

[HarryBack]

actually, no. I have replaced very few control boards on inserts.....none that come to mind. Not to say they dont go "out", but its almost never the board. Does it run differently in stove mode?

 

[Papaw]

No it does the same.
Not an issue any more. I was taking some pictures to illustrate what is going on. I was going to do a before and after scraping. I did the before but then I got a call they will be here in two hours to pick it up. I don't care to scape it now so they can see what is happening after about 5 hours. I'll put the pictures I have up later.
Thanks for caring and sharing.
Tom

 

[GVA]

Well It may be a bit late here but You said that you are running the blower at high You could try putting it between high and low and let the stove control the speed of the blower.
and in addition to that did the stove ever go into a low fire condition? Or was it always burning like the picture in this thread?

and finally you have hit quite a low temp there this season I've hit maybe 25* once maybe twice this season, can you describe your location a bit?

 

[Papaw]

Well It may be a bit late here but You said that you are running the blower at high You could try putting it between high and low and let the stove control the speed of the blower.
and in addition to that did the stove ever go into a low fire condition? Or was it always burning like the picture in this thread?

and finally you have hit quite a low temp there this season I've hit maybe 25* once maybe twice this season, can you describe your location a bit?

Hi GVA,
Yup it's too late they removed it this afternoon. It was discovered that no high temp silicone was applied to the joints. I did hand them the tube at about $10.00.
I have put the control in the middle through this ordeal. Now that you mention it I don't recall the stove going into low mode.
I am about 30 miles north of Charleston WV. My outside water pipes froze too even with a heat tape.

FYI; A very reliable source told me the differential on the room sensing thermistor is 5 degrees for those waiting for their stove to come back on.

I was going to show before and after scraping but knowing they were coming I only have the before pictures.
I'll let the pictures speak for themselves.

 

[GVA]

On page 19 of the Harman Accentra Pellet Insert manual on the left side of the page last two paragraphs where it has the wod required it shows a definite relationship between draft and voltage. Indicating less draft with higher voltage. IMO.

Papaw
PS: The medalion picture is after two weeks of use. Click on it to see. The hopper door is open to enhance the view of the fire.

I just wanted to check here on these
first the slower the comb blower turns (less voltage)the less draft you will have.

second if you have to open the hopper to enhance the view of the fire than you probably have a fresh air intake problem. though when one opens the hopper the flame does react some.....................

 

[Papaw]

I just wanted to check here on these
first the slower the comb blower turns (less voltage)the less draft you will
have.

That's what I got out of the text too. That's why I mimicked your setting since our line voltage was close. I ended up with a blue to white to yellow flame but I'll bet most of my heat was going up the chimney. I realize this is akin to setting the timing on a vehicle with out a timing light but not having a draft gauge I was doing the best I could.

second if you have to open the hopper to enhance the view of the fire than
you probably have a fresh air intake problem. though when one opens the
hopper the flame does react some.....................

I did ask that question to those in the know but I couldn't get a straight answer. That makes sense to me. In the long shot picture I took that to show I had the two windows open to provide more fresh air. (combustion air) There are louvres on both sides at the top inside the side doors to allow air to get to the back of the unit.
I've learned so much with the help of you guys I think I'll open a pellet stove store ;^).

I'll be trying the Mt Vernon AE. I grew up in a town by that name in NY state.

BTW; anything closer that a five degree differential on the thermistor the stove would be kicking on and off all the time.

I gotta say this has been fun. Kept me busy for the last two months.

Thanks all, Tom

 

[Papaw]

Update, this is a picture of my so called $400.00 hole.