harmon absolute p43 noise any time break vac seal

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nicu

New Member
Dec 17, 2020
9
new york
Just had installed on Tuesday any time I open door to scrape pan, load pellets or check ash pan as soon as seal is made not sure if there is a secondary fan but it sounds like a combination between fan blade hitting metal to something not engaging can be very loud will last anywhere from 30 sec to 2 mins before it stops sound pulses then everything seams normal any thoughts?
 

SciGuy

Feeling the Heat
Aug 17, 2007
363
Constableville, NY
Here is sound after I closed front door


Yikes!!!!!! It sounds like the combustion fan scraping its cover. You could shut the unit down, pull the ash pan and then combustion fan cover and see if it's marked up by the blower wheel scraping . If a dealer installed the stove he ought to come out and make things right.
 

nicu

New Member
Dec 17, 2020
9
new york
Yikes!!!!!! It sounds like the combustion fan scraping its cover. You could shut the unit down, pull the ash pan and then combustion fan cover and see if it's marked up by the blower wheel scraping . If a dealer installed the stove he ought to come out and make things right.
They will be here Monday . So question does that fan only run for a short while after you break vacuum? All other operation seem normal
 

SciGuy

Feeling the Heat
Aug 17, 2007
363
Constableville, NY
nicu,

The combustion fan should continue to run after you open the stove door. The pressure drop switch will turn off the auger feed when the door is open but the fumes from the currently burning pellets must continue to be exhausted or the house would be filled with fumes every time you cleaned the burn pot while a burn is going on. If one just left the door open permanently I suspect that the combustion fan would continue to run until the exhaust temperature dropped to 90*F as it does in a normal shut down. This is a safety feature not a bug in the system.
 

nicu

New Member
Dec 17, 2020
9
new york
Thanks for the info this is my first pellet stove, always had woodstove. So I have shut the stove down several times doesn't make noise then.
 

Ssyko

Minister of Fire
Nov 6, 2017
4,293
Lorraine NY
If I remember right the stove will sence a vacuum leak when the door is opened and will ramp up the combustion blower to evacuate smoke. Sounds like the blades are hitting the housing.
 

gfreek

Minister of Fire
Nov 5, 2010
1,561
WNYS
This is a new stove? What the heck ! Again, it's a good idea to ask the dealer to do a pre -burn before delivery . This may have been avoided.
Can this be similar, video included
Here's the video....

:
 

nicu

New Member
Dec 17, 2020
9
new york
This is a new stove? What the heck ! Again, it's a good idea to ask the dealer to do a pre -burn before delivery . This may have been avoided.
Can this be similar, video included


:
Yes just had installed Tuesday
 

gfreek

Minister of Fire
Nov 5, 2010
1,561
WNYS
Ok . Since it's under warranty have you contacted the dealer and their answer ?
 

gfreek

Minister of Fire
Nov 5, 2010
1,561
WNYS
Let us know the outcome , thanks
 
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gfreek

Minister of Fire
Nov 5, 2010
1,561
WNYS
There you go. Simple enough . Thanks for the update
 

fdirosa

New Member
Dec 25, 2021
2
New York
I just had a Harmon Absolute 43 installed December 22, 2021 and when I open the lid to put pellets in I hear the exhaust fan pick up speed then the loud scraping noise happens. Closed lid after a little while the scraping stops. I open the door when it is not burning pellets same thing with exhaust fan on. I took the exhaust cover off and did the same test and opening the pellet lid doesn't cause the scraping to occur anymore but when opening the door to the pellet stove it still does. This is a brand new stove. Is Harmon quality going down hill? They can't even install an exhaust fan correctly to avoid scraping. This seems like a defect in design since the exhaust fan blades are literally one hair thickness from the metal.
 

gfreek

Minister of Fire
Nov 5, 2010
1,561
WNYS
I just had a Harmon Absolute 43 installed December 22, 2021 and when I open the lid to put pellets in I hear the exhaust fan pick up speed then the loud scraping noise happens. Closed lid after a little while the scraping stops. I open the door when it is not burning pellets same thing with exhaust fan on. I took the exhaust cover off and did the same test and opening the pellet lid doesn't cause the scraping to occur anymore but when opening the door to the pellet stove it still does. This is a brand new stove. Is Harmon quality going down hill? They can't even install an exhaust fan correctly to avoid scraping. This seems like a defect in design since the exhaust fan blades are li
Time to call the dealer and have them service it. Again if they test fired it before delivery this may have been caught..
 

Mt Bob

Minister of Fire
Oct 31, 2013
3,953
park county montana
I just had a Harmon Absolute 43 installed December 22, 2021 and when I open the lid to put pellets in I hear the exhaust fan pick up speed then the loud scraping noise happens. Closed lid after a little while the scraping stops. I open the door when it is not burning pellets same thing with exhaust fan on. I took the exhaust cover off and did the same test and opening the pellet lid doesn't cause the scraping to occur anymore but when opening the door to the pellet stove it still does. This is a brand new stove. Is Harmon quality going down hill? They can't even install an exhaust fan correctly to avoid scraping. This seems like a defect in design since the exhaust fan blades are literally one hair thickness from the metal.
Anyone that has removed that cover could have bent the fan. The dealer,installer,etc. People sometimes do it when they clean their stoves. If you have removed that cover, could have been you. If the stove was dropped, it could have affected the motor mounts. The bottom line is the installer should have checked full functionality of the stove, if it is them you bought it from.
 

fdirosa

New Member
Dec 25, 2021
2
New York
Time to call the dealer and have them service it. Again if they test fired it before delivery this may have been caught..
They did the test fire. That didn't cause the issue. What causes the issue is when you open the hopper lid with exhaust fan on for a little while to get the RPM up then it makes the noise. They didn't do that. Definitely did not open the door when the fire is raging. Regardless. Why does the installer have to do the QA for manufacturing defects?
 

Mt Bob

Minister of Fire
Oct 31, 2013
3,953
park county montana
For the same reason all new vehicles go through a PDI, pre delivery inspection. with a through road test. They are paid to do it, to catch any manufacturing or assembly flaws.
 
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Bear Camp

New Member
Feb 15, 2022
6
Western PA
Hello all, new member here.

I am so happy to find this web site! My 2 month old Absolute 43 worked great until this past week (not constantly, only about 2 dozen bags through it when i am there). When I open the hopper to add pellets it started making the EXACT same grinding noise from the combustion motor fan blade assembly..... THEN it ground itself to a halt, stopping the combustion motor dead (with the fire still brightly burning)! When the tech arrived, a couple of days later, he of course question me (as if I had something to do with this - NO!!). When he took the solid cover off the blade assembly one of the blades had caught (for some unknown reason) and broke most of the way off. As a short term repair (until he will be able to get one in stock), he removed the rest of the broken blade and made sure everything was straight. (He checked in the compartment for any obstruction, and verified no lateral movement with the motor bearings) The absolute started fine (with a minor vibration because of the missing fan blade). THEN, while he was still here, I opened the hopper cover. Guess what..... it is grinding again (but running). I stopped at the dealer and he was skeptical at first, then I told him about this site and people having the same issue with the 43. The owner called the factory while I was in his shop. HARMAN has NEVER heard anything about this issue!! A new blade assembly is on order, any the dealer said he will make it right. My observations: 1) the blade assembly is much more convoluted than any other Harman blade system, 2) there is very little clearance behind the back of the blade and the casting. The blade assembly sits on a collared shaft and tightens with a nut. There is no set screw to move the blade assembly forward.
 

Mt Bob

Minister of Fire
Oct 31, 2013
3,953
park county montana
Well you can tell Harman I think this is probably the 5th time it has been reported, on the net. The motor is an external rotor EBM PAPST, the impeller is not adjustable. I can only think of 3 things that could happen to change the spacing-- 1 the shaft is pressed into the rotor,rides in bearings, and has slid out.Very doubtful to me. 2 the rubber mounts are giving too much. 3 the clearances are so tight, and something in the stove flexes/warps especially when hot.Either the cover or the back of the stove where the fan mounts. Keep us in the loop, please.
 

Bear Camp

New Member
Feb 15, 2022
6
Western PA
Update (from February 15, 2022): Well, my POS HARMAN ABSOLUTE 43 is still not fixed yet! It is grinding away and making so much noise I can barely tolerate it. I was told the impeller I need for my combustion motor is on backorder until mid March. (No one even knows why this happened, AND if a new impeller will be a permanent fix!) I am so sorry I bought a pellet stove. Especially a HARMAN ABSOLUTE 43! Buyers beware!