Rhythmic vibration and buzz from Harman 52i combustion fan

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Peterfield

Minister of Fire
Dec 12, 2013
1,394
New Hampshire
Hey all,

This heating season, the combustion blower of my 2014 vintage Accentra 52i has developed a rhythmic vibration where every 10 second or so it will begin to give off a low pitched buzzing sound and then the sound will mostly fade away from 10-15 seconds. It’s getting so you can set your watch to it. This happens in test mode and also during startup and continues after pellet ignition. I’ve read up on older posts and it seems that I will be in the market for a new blower motor. I have a service call in for a cleaning and possible blower replacement but before he calls back, I am looking for recommendations of better third-party motors out there over the OEM blower. Thanks in advance.

Paul
 
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is it your motor or hopper lid? my hoper lid will vibrate when pellets get low to the point it scared my little one and she thought something was wrong and unplumbed the stove..
 
Hey all,

This heating season, the combustion blower of my 2014 vintage Accentra 52i has developed a rhythmic vibration where every 10 second or so it will begin to give off a low pitched buzzing sound and then the sound will mostly fade away from 10-15 seconds. It’s getting so you can set your watch to it. This happens in test mode and also during startup and continues after pellet ignition. I’ve read up on older posts and it seems that I will be in the market for a new blower motor. I have a service call in for a cleaning and possible blower replacement but before he calls back, I am looking for recommendations of better third-party motors out there over the OEM blower. Thanks in advance.

Paul
Harmans seem to have a habit of amplifying vibration noise through the metal guards in the back of stove. There was a individual who was selling combustion fans for 125.00 on E-Bay Is it possible the noise is coming from auger motor and it makes noise when stove is first started but after it is run for a hour or so the noise quits?
 
The technician called and wants to do a thorough cleaning to include the blowers and see if that quiets things down. If not, then the third-party motors seem interesting.
 
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My hopper lid does have that vibration as well and if I press on the lid or shimmy the stove a bit, it stops. The fan however buzzes on.
 
Wow.Do you pull your insert,and service it yourself?Your blower probably has bronze bushings,instead of bearings(for noise),and,companies that pull/clean and reinstall inserts do not lube the motors,as,the factory info does not prescribe this.There are many posts here about lubing bushing and bearing type motors,never advertised by the manufacturers,as they want to sell parts and service.Your motor is 4 years old,never had a drop of oil added,and,possibly not cleaned properly,I do not know what you are expecting.The blower motor is a wear item,same as brake pads.There are so many threads about lubing these motors is because we try to save us,and other posters,money.Service technicians do not use a needle to inject oil into sealed bearings,nor oil bushings.My advise is to tell the upcoming technician to bring a new blower motor with him/her,to install.And,if you really want a long lasting motor,it will be ball bearing(noisy)and very expensive.Sorry I ranted,but,I have seen this issue so many times.
 
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Wow.Do you pull your insert,and service it yourself?Your blower probably has bronze bushings,instead of bearings(for noise),and,companies that pull/clean and reinstall inserts do not lube the motors,as,the factory info does not prescribe this.There are many posts here about lubing bushing and bearing type motors,never advertised by the manufacturers,as they want to sell parts and service.Your motor is 4 years old,never had a drop of oil added,and,possibly not cleaned properly,I do not know what you are expecting.The blower motor is a wear item,same as brake pads.There are so many threads about lubing these motors is because we try to save us,and other posters,money.Service technicians do not use a needle to inject oil into sealed bearings,nor oil bushings.My advise is to tell the upcoming technician to bring a new blower motor with him/her,to install.And,if you really want a long lasting motor,it will be ball bearing(noisy)and very expensive.Sorry I ranted,but,I have seen this issue so many times.
I agree and will add that quality motors will use replaceable bearings if possible but in many instances when you hire a technician they will install a new motor and your problems should be over. If they did the same labor and oiled a bearing it would maybe last the season but next fall you would be calling him again and saying you didn't fix my problem. This is why a lot of owners do their own repair. But after taking a stove apart twice for oiling a bearing in one season we see that replacing that motor is often the smart move especially if that motor is tough to get at. Plus of course that motor will never fail when you have time to fix it or you have a spare on hand.
 
Wow.Do you pull your insert,and service it yourself?Your blower probably has bronze bushings,instead of bearings(for noise),and,companies that pull/clean and reinstall inserts do not lube the motors,as,the factory info does not prescribe this.There are many posts here about lubing bushing and bearing type motors,never advertised by the manufacturers,as they want to sell parts and service.Your motor is 4 years old,never had a drop of oil added,and,possibly not cleaned properly,I do not know what you are expecting.The blower motor is a wear item,same as brake pads.There are so many threads about lubing these motors is because we try to save us,and other posters,money.Service technicians do not use a needle to inject oil into sealed bearings,nor oil bushings.My advise is to tell the upcoming technician to bring a new blower motor with him/her,to install.And,if you really want a long lasting motor,it will be ball bearing(noisy)and very expensive.Sorry I ranted,but,I have seen this issue so many times.

We’re on the same page. I expect the blowers will need replacing and was just wondering if I should be looking at OEM or third party blowers. The technician has told me before that the bearings on these motors are sealed and can’t be lubricated. I think he just wants to double check and clean the fan blades to make sure it’s in balance.
 
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Harmans seem to have a habit of amplifying vibration noise through the metal guards in the back of stove. There was a individual who was selling combustion fans for 125.00 on E-Bay Is it possible the noise is coming from auger motor and it makes noise when stove is first started but after it is run for a hour or so the noise quits?

Any solutions for the vibration noise through the metal guards in the back of the stove?
 
Any solutions for the vibration noise through the metal guards in the back of the stove?

Yes. Red RTV Silicone where it's rubbing. I found 2 screws on my Distribution Fan (Harmon XXV) that were impacting the fan housing. You can also put block of something to hold pressure on the sheet metal. I did not need that after some RTV.
 
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Well, the technician came and deep-cleaned the stove and listened to the noise the combustion/exhaust blower was making. He admitted it was a little louder than normal and that replacing the blower is a b*tch of a job. It was late in the day and I got the distinct impression he just didn’t want to tackle the job. So, my question now is how difficult is it to do. From videos I see that sometimes the fan blade has to be cut off to allow for removal of the motor. I know I can call the dealer where I bought the stove from and they’ll do the job but is it an easy DIY operation or should I leave it the hands of the folks that have the tools and the talent?
 
Well, the technician came and deep-cleaned the stove and listened to the noise the combustion/exhaust blower was making. He admitted it was a little louder than normal and that replacing the blower is a b*tch of a job. It was late in the day and I got the distinct impression he just didn’t want to tackle the job. So, my question now is how difficult is it to do. From videos I see that sometimes the fan blade has to be cut off to allow for removal of the motor. I know I can call the dealer where I bought the stove from and they’ll do the job but is it an easy DIY operation or should I leave it the hands of the folks that have the tools and the talent?
Hey how did you make out with combustion blower doesn’t look that hard todo ?
 
Hey how did you make out with combustion blower doesn’t look that hard todo ?

Haven’t tackled it yet but my wife says she’s getting tired of listening to it. I guess it will come down to getting the blade off the front. Taking the motor off seems pretty straightforward.
 
Haven’t tackled it yet but my wife says she’s getting tired of listening to it. I guess it will come down to getting the blade off the front. Taking the motor off seems pretty straightforward.
Where did you buy the new motor did you get a good deal
 
I have seen good deals on Amazon for Gleason Avery motors and would have bought one of those but since the dealer was sending out a tech, he brought one out and although it works great, it was no deal.
 

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Be careful on Amazon. I bought an advertised Gleason Avery Combustion Fan Motor and they sent me a fasco. Charged me 97 bucks for it and to rub salt in my wound they shipped it from another supplier with an invoice for 54 bucks in it. Got a return and shipped it back. Dealer claimed they didn't realize that they didn't change the picture. Yea right. I guess they thought I was born yesterday.
Ron
 
It’s not a hard job but I’m not as flexible as I used to be so I had it done. The tech didn’t take long at all to put it in.
Glad you got it fixed my stove is around the same age as yours so I was pumping for info case I had same problem.
 
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