New PE Blower hum

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halightw

New Member
Hearth Supporter
Mar 22, 2009
2
Northwestern Ontario
We just purchased a Pacific Energy wood insert. It has been professionally installed by the local dealer here and is heating our house quite nicely now. The amount of heat it produces is excellent. My only disappointment is that the blower motor makes a very loud hum, especially on the lower settings. It makes it kind of unpleasant to sit nearby while it is on. It seems to go away on high, but then the roar of the airflow is so loud on that setting it really wouldn't matter anyway. The humming is so loud that I can hear it on the 2nd floor of the house and have resorted to running a small portable fan across the front of the fireplace at night so that the humming doesn't keep me awake at night. Is blower motor hum a normal thing? Should I complain to the dealer or manufacturer?
 
Not familiar with your stove but usually when a blower has excessive hum there is too much drag on the motor shaft.

With the stove OFF can you spin the blade manually (or use a vacuum cleaner on blow) and see if it spins freely and gradually slows down to a stop.
If the blades have a lot of dirt build-up that can make it a bit noisy because of the drag.
There is also a good possibility the blades are hitting something and may need to be repositioned on the shaft.
Bad fan motor.
 
Had this exact problem. The motor was humming and it traveled through the wall to the upstairs. Manufacturer replaced the motor and it was quiet for 2 weeks and has started up again. Working on another replacement right now. The fact that a new motor was super quiet was encouraging and in two weeks there was not enough time for it to get dirty. Either it is a bad batch of motors or some on here have wondered if it is getting too much air. Havent figured out how to restrict the airflow any as it is all open in the back.

If I were you I would try to get motor replaced by the dealer as a start.
 
Thanks for your replies, I just realized I posted this in the wrong forum by accident, should have been in wood, but I guess blower motors are common to all anyway. I am going to get the dealer to replace the motor. It's brand new, I've been running it for 3 days solid and the motor isn't getting any quieter. I thought maybe it had to break in or something, but no luck.
 
Same thing just happened to me! I just had the blower installed on my pe spectrum woodstove...nice and quiet all day and just started this ridiculously loud hum...did you ever find a fix for it?
 
Well guys, the answer is obvious, they don't know the words. :-S That kind of issue can be a million things, but are best handled by the dealer under warranty. A few makers have acknowledged problems with blowers over the last few years and that may be the case with PE. Best I can say is contact the dealer, or... you can teach it the words.
 
The hum is from the rheostat throttling back the blower too much. You have to speed up the blower a bit to get rid of the hum. I believe the PE motor is like 2,800 rpm, which means that if you try to lower it beyond 1,400 or so, you are going to get a hum and potentially overheat the motor. The only solution is to replace the blower with a slower speed blower. You could try adjusting the pot on the rheostat to see if you can get it any better, but you probably won't be able to fully solve the problem.
 
It would be helpful to hear from other Summit/T6 owners that have older stove/blowers to see if they are hearing this hum too. I just received a new blower motor assembly from PE. It has a ~60 cy hum. The hum is from the motor and is always present. At full speed the hum is somewhat masked by the blower air noise but it is still 100% there and at the same volume as at low speed. I suspect there may be a bad motor batch here, checking on this.

As a test I have listened to the unit on and off the stove. Off of the stove, the hum is present, but barely audible. Attaching it to the back of the stove amplified the hum greatly as the rear heatshield became a sounding board. I have heard speed controller hum at low speed in my other test fan motor. That fan has a cheap bathroom fan speed controller on it and its hum does reduce at higher speeds. This hum is constant and more apparent because the PE blower is a exceptionally quiet.
 
PE definately has a bad batch of fans installed in their stoves. This is the first year with my PE super and the original pair of fans were badly out of balance creating a horrible rattle. The replacement fans ended the rattle but one of the two fans has a hum or maybe more of a whine that is somewhat annoying. I have to turn the tv up a little to here over that fan. The noise is more noticable at high speed. I haven't told the dealer yet probably because it's such an improvement from before. I'm not sure if I'm just being to picky
 
Don't have these issues with my Summit insert.
I did replace the motor/fan assy last year after 3 seasons.
New one don't hum either. I bought it online, was cheaper then from PE.
Has very faint hum, nothing major.
 
Any shaded pole motor hooked up to a rheostat will hum. The more you slow it down, the more it will hum. Not sure who PE is using for a motor supplier and how much they have the rpm's throttled back. If you try to reduce the speed below about 50% that is when you can get a pretty annoying hum and the motor itself will heat up and eventually burn itself out. I'm guessing that the rheostats are out of adjustment on some of these motors. That is an easy 5 min fix if it is the problem.
 
New one don’t hum either. I bought it online, was cheaper then from PE.
Has very faint hum, nothing major.

?? Could be I am being over aware, but going from a silent stove to one with a hum is noticeable enough to comment on. The fan is very quiet, certainly much quieter than a Harley ;). That's probably why the hum is predominant. No balance problem noted with the fan, just the hum. I may try resting it on bricks instead of screwing it to the stove to decouple the noise transmission from the rear heat shield.
 
I did some experimenting with the fan when it was noisy and found that when I pressed on the casing it is in, the noise stopped. It does seem to conduct noise against the heat shield. I checked to make sure the screws were nice and tight and they were. It seems to be more a vibration issue from the centre of the casing against the heat shield. Which got me to thinking...I wonder if a bead of heat resistant caulk would be enough to reduce the vibration? Would that be safe? I sure wouldn't want to harm anything...but it makes sense to me that it might help.
 
woodsprite said:
I did some experimenting with the fan when it was noisy and found that when I pressed on the casing it is in, the noise stopped. It does seem to conduct noise against the heat shield. I checked to make sure the screws were nice and tight and they were. It seems to be more a vibration issue from the centre of the casing against the heat shield. Which got me to thinking...I wonder if a bead of heat resistant caulk would be enough to reduce the vibration? Would that be safe? I sure wouldn't want to harm anything...but it makes sense to me that it might help.

Is your fan(s) running true?
 
woodsprite said:
I'm not sure...how would one know?

Look into the vanes of the fan and look to see if the vanes are wobbling on the shaft as the fan begins to spin (or as it slows down). Sort of like an out of balance tire.
 
I can't see...the whole thing is enclosed. :( Unless I could peer thru the vents, but considering they are underneath on the back side of my stove it would require the skills of a contortionist...
 
BG, I have a new blower, and do not hear much of anything with the fan on the lowest rheostat level, actually a couple times i thought the fan was off when it was on the lowest setting. On high, it is much quieter than our gas insert's fan.

What you mean by 60 cycle hum, I know what it looks like on an ECG, but not exactly sure how it would sound?

I tightened all the shroud screws, when i installed the unit, would washers between the shroud and stove help?

to date, am really happy with the unit, so far, n=2 months.
 
Thanks, it could be this unit has a bum speed controller. It's good to hear that your blower is not doing this. Yes, it is a nice quiet blower. That's probably why the hum is noticeable. I remember reading your post when you got the fan and before installing made sure that everything was tight and snug.
 
BeGreen said:
New one don’t hum either. I bought it online, was cheaper then from PE.
Has very faint hum, nothing major.

?? Could be I am being over aware, but going from a silent stove to one with a hum is noticeable enough to comment on. The fan is very quiet, certainly much quieter than a Harley ;). That's probably why the hum is predominant. No balance problem noted with the fan, just the hum. I may try resting it on bricks instead of screwing it to the stove to decouple the noise transmission from the rear heat shield.

I am assuming the blower for your freestanding is a completely different beast than the insert blower.
The insert blower mounts on rubber bushings, I get more noise from the casing around the insert vibrating at certain temps, then the actual fan or motor. And agreed, if your going from a completely silent stove, to a fan it will be much more noticeable. I honestly don't notice much of a hum even at lowest setting. Maybe I'm lucky, or maybe I just am used to it, and not used to having a quiet, freestanding unit.
Just turn the TV up a lil louder.
 
TV?? Whazzat?

The freestanding stove blower is also isolated with rubber bushings in the housing. Could be the controller that is humming, not sure.
 
In installed my fan on Friday. It is relatively quiet even on high. I am not that thrilled with it though. I thought It would push more heat from the stove. I really don't see much of a difference to be honest.
 
Could it be harmonic vibration of surrounding metal? I have an exhaust fan which, at mid speed, generates an annoying hum, or singing noise. Fan checks out fine and increasing or decreasing the speed sufficiently resolves it. Is there a risk to sticking a magnet on the housing to see if I can change the noise? Did think of the caulk, but first need to isolate the noise. Thanks.
 
The problem is the 3,000 rpm motor. If you run it full speed you get a lot of air noise. If you try to run it too slow you are going to get a hum due to the rheostat applying too much resistance to the system. You are trying to throttle back the motor too much and it doesn't like it and will eventually overheat and fail. A better choice would be to select a lower rpm motor like a 1,250 and run it at full speed.

Either that or the three mounting points are too flimsy and you are getting a vibration in the housing. Stiffer is better. So you could stiffen the sheet steel with some ribs or try a band-aid fix of applying damping material.
 
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