Quieter Blower Fans for Harman?

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trogers

New Member
Aug 25, 2008
183
Southern NH
I love my new Accentra Insert, but the fans are a pretty loud. Does anyone know if Harman sells a quieter version of the blower fan?
 
Yes i have noticed that as well, it makes it hard to watch tv when is on hi.
my XXV blower is quieter don't understand that.

I am going to keep an eye on this thread.
 
The noise is undoubtedly inherent to the stove`s design regarding the warm air distribution channel / heat exchanger and the fact that the stove is steel construction that tends to act as a sounding board to amplify noise..
The motor and impeller itself is nearly silent when separated from the stove and allowed to run. I don`t believe much if anything can be done to reduce the sound it makes.
I do find that cast iron stoves deaden the sound better due to the mass of the casting itself . Ref: Quad Castille model.
 
I think it is more of a flow noise issue than the actual fan. I was thinking of modifying the distribution air intake to draw air from below the hearth via a large hole bored into the insert framework (part that the stove slides in and out of) and hearth or maybe just draw air from the backside of the unit. I have not actually done this yet, it is all just a thought at this point.
 
Anton Smirnov said:
If the problem on the accentra is a flow issue, is there any way to gasket the fans to better direct the flow of air? (I ask because I know an older Macintosh that I owned had a bad gasket, and it increased the noise alot)

Any of of the pellet pros want to chime in on this thread?

You should be able to determine if it`s excessive vibration that`s causing the noise. I do believe that most fan assemblies create some noise and vibration but it is a different sound than the air flow noise. If you feel noise is indeed excessive you should check the impeller for improper balance issues or in need of a cleaning. It`s also possible the motor bearings could be slightly worn and a bit noisy.
You would have to remove the motor and take the impellar off the shaft (with a hex wrench) to clean it thoroughly.
It`s probably not likely that adding a gasket will do anything since you would have to crank it tight to the stove body anyway and that would just transfer the vibration anyway.
The only way to totally stop the vibration from the fan assembly is to isolate it from the stove with a flexible heat resistant gasket and that`s gonna be hard to do.
 
I wasn't thinking about the vibration.

your original post about the blower noise coming from the flow path got me to thinking about sources of turbulant flow _outside_ the fan

if there is a gap between where the air exits the blower & where the air needs to go, that can cause turbulance.

turbulance = noise
(also, turbulance = better heat transfer)
 
The noise seems to be more a sound of the air movement...I think. I'm thinking that maybe they are all just loud? I'll look at the fan and check to see if thereis any vibration coming from there.

Thanks.
 
After laying in front of the stove for about an hour I have pin-pointed the sound coming the intake fan in the bottom of the stove. The blower up top that distributes the air isn't all that loud.

Any thoughts?
 
When your stove is running, put a towel over the intake vent. Noise is much better which shows that it is a flow noise issue which is why I want to bring the intake air from somewhere else.
 
I also noticed that there is much more noise that comes out of the bottom. I tried the towel trick, but I was afraid it would catch fire if left unattended. I found a small piece of flame proof cloth at home depot they sell as a flame protector for soldering. I cut it in half, rolled up each half, and tucked it between the floor and the cast iron lip on the front of the stove. Helps cut the noise a lot.
 
I purchased a Harman fireplace insert pellet stove a few weeks ago (November, 2008) and have a loud humming noise coming from the blower motor, especially at the medium setting. I can live with the blower noise itself, but the humming noise is very annoying. The installer is coming today to install a new igniter which was faulty when the stove was first installed a two weeks ago. I will have him check the motor noise when he arrives and post a follow up. Also, my stove did not come with a cooling fan on one of the motors (not sure which one) which my installer said he would order. A few days ago, when I called to ask when the fan would be in, he then told me that Harman had discontinued the fan and that it was no longer necessary. I am not sure if this is so and would welcome any input. Maybe the lack of a fan on the shaft coming out of the motor is the reason for the vibration I am hearing.
 
ces001 said:
I purchased a Harman fireplace insert pellet stove a few weeks ago (November, 2008) and have a loud humming noise coming from the blower motor, especially at the medium setting. I can live with the blower noise itself, but the humming noise is very annoying. The installer is coming today to install a new igniter which was faulty when the stove was first installed a two weeks ago. I will have him check the motor noise when he arrives and post a follow up. Also, my stove did not come with a cooling fan on one of the motors (not sure which one) which my installer said he would order. A few days ago, when I called to ask when the fan would be in, he then told me that Harman had discontinued the fan and that it was no longer necessary. I am not sure if this is so and would welcome any input. Maybe the lack of a fan on the shaft coming out of the motor is the reason for the vibration I am hearing.

OK, the installer came and replaced the igniter. It now works like it should. He also replaced the fan which turned out to be attached to the auger motor. As far as the noise is concerned, he told me that the motors make a certain amount of noise and that is the way it is supposed to sound. The room that the insert is in is newly remodeled with very little furniture which may be contributing to the noise amplification. We plan on adding a sofa and two recliners soon and will post the results regarding the noise levels.
 
Generally speaking, the movement of air is the culprit. A noisy motor is usually the sign of a dying component, rather than a nuisance noise from the component. Sometimes, the noise of air movement is a compromise the design engineers make for the sake of getting lots turbulent airflow across the heat exchanger. Not making excuses, just saying that sometimes, fan noise takes a back seat to heat transfer.
 
I had the same problem with my Enviro EF-5 pellet stove. The original fan was unbelievably loud! The newer models are quieter; I believe they reduced the speed of the fan as the actual fan units seem to be similar. I replaced my convection fan with a used tangential fan, but it's still noisier than I'd like. I am considering mounting a blower remotely and bringing a duct in through the bottom plate behind the fire box but this will require a lot of work! I think it will be important to minimize air turbulence noise as well, by matching the duct cross-sectional area with that of the heat exchange entrance.

Snoqualmie Stove Works in WA is working on a pellet stove that is radiant, like a woodstove. It will apparently will have a convection fan for those who want it but it is designed to radiate heat rather than blow it. Possibly the best of both worlds.

:) Stuart
 
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