Why is the Fan Blade Different?

[jasonmunson]

Things keep getting changed and upgraded in the Pellet Stove World. Motors and fan blades are one of the things that have been upgraded in the past few years.

You may have noticed that the fan blade that came with your new motor looks different and may be smaller than what is on your old motor. It seems logical that a larger fan blade will produce more air and so using the old fan blade would be better.

What the motor designers have found is that a larger fan blade creates more drag and reduces the speed of the motor. This increase in drag increases the stress on the motor and causes it to fail faster.

The new motor design includes a fan that has been meticulously manufactured to produce the balance of proper air flow while not over stressing the motor.

DO NOT use your old fan blade on a new motor. It usually results in lower motor performance so the stove doesn’t get proper air flow. The result is usually is excess black soot on the glass and in the stove.

by Jason Munson
Pelletstovepro

 

[Don2222]

Hello Jason

Do you have some pics to show what you are talking about?

I have seen 9 petal fan blades and 11 petal fan blades and fan blades that are larger that come with a deeper fan housing. IMO, It seems these fan blades are designed for the stove body that they come with.

Example1:
The Englander 25-PDVC has the small blade 11 petal combustion blower part # PU-076002B
The Englander 10-CPM has the larger blade 11 petal combustion blower part # PU-076002S
As far as I know these fan blades have always been this same configuration. It seems to me that the large petal combustion blower is needed for the 10-CPM to mover more air when burning corn or cherry pits because the higher heat released with these fuels need more air flow.

Example2:
In the case of this Travis small combustion blower. See pic below. Since the large blower motor and the small blower are both 3,000 RPM then then the only way to change the air flow is to use less petals. The small blower has 9 petals and the large blower has 11 petals. The small blower has larger petals to adjust the CFM even more. IMO, that is by design for the correct CFM for the smaller stoves. Travis has been making them that way for some years.

What the motor designers have found is that a larger fan blade creates more drag and reduces the speed of the motor. This increase in drag increases the stress on the motor and causes it to fail faster.

I also tend to disagree with this statement above. The motor wholesalers do not sell all the different fan blades for the pellet stoves. Harman has their impellers and Whitfield have their impellers and vary with the different model of stoves. Here again, all the motors are 3,000 RPM so to change the CFM, I.E. air flow, different impellers are used. IMO it looks like the stove designers not the motor designers select the proper impellers for the design of their stoves. If the shell of the stove does not change, then the impeller size should not either, unless there is an inherent problem with the stove. In the case of the Magnum Baby countryside, the stove designers selected an upgraded higher speed exhaust blower. (105 CFM instead of the original 85 CFM) This change allows more air thru the burnpot and air thru the stove. This has made the Baby run smoother and have less build up of ash. Just my 2 cents.


Please explain more and pics are more helpful.

 

[webbie]

Jason, although we welcome good information on the forum, cut and pastes from your own blog are not needed. If you have a lot of such articles and opinions (and you do!), you can simply put a single link to your blog in your signature:
http://www.pelletstovepro.com/pellet-stove-parts/

This way the content won't be in multiple places all over the internet and people will be able to read everything you write.

Thanks!

 

[smwilliamson]

This is the type of soft spam I told you guys about. I wouldn't wait around for any type of response, much of what he is saying here is untrue to an extent. Notice he cites no examples.

 

[jasonmunson]

I know I've had a few customers email pics in last year but I can't seem to find them. Where I have seen this to be most common is with the Quadrafire Mt Vernon Stoves. There is a Fasco replacement that works well with it but the blade design is different from the original. I've also had some Kozi users ask about it being different. It's not a real common problem but last year I had a lot of people have questions about it.

 

[jasonmunson]

This is the type of soft spam I told you guys about. I wouldn't wait around for any type of response, much of what he is saying here is untrue to an extent. Notice he cites no examples.

Scott, see my two examples listed below. This isn't spam. This is a real issue I have customers ask about.

 

[jasonmunson]

Jason, although we welcome good information on the forum, cut and pastes from your own blog are not needed. If you have a lot of such articles and opinions (and you do!), you can simply put a single link to your blog in your signature:
http://www.pelletstovepro.com/pellet-stove-parts/

This way the content won't be in multiple places all over the internet and people will be able to read everything you write.

Thanks!

BossMan, this is my first attempt to post an article that I think is of value on your forum or any forum for that matter so I really appreciate any suggestions you can give me.

 

[smwilliamson]

BossMan, this is my first attempt to post an article that I think is of value on your forum or any forum for that matter so I really appreciate any suggestions you can give me.

Don't cut and paste information from one place to another, keep unique websites unique. When you take an article from your blog and cut and paste it around the net, search engines view that as information which is not unique and therefore maybe not as relevant. Hurts your site and Craig's site.

 

[smwilliamson]

Scott, see my two examples listed below. This isn't spam. This is a real issue I have customers ask about.

pics or it didn't happen...

The new motor design includes a fan that has been meticulously manufactured to produce the balance of proper air flow while not over stressing the motor.

Can you back this up with a fact or a quote from a manufacturer? You know, it would be easier in most cases to put the impeller on a stronger motor. Quad changed its supplier for the combustion motors for the AE so it's only reasonable to note that the impeller fins may have changed too.

Who's selling motors without impeller anyway? Except for Harman that it....

 

[webbie]

If anyone wants to write truly great and accurate informational articles (not something just for SEO or biz), I will put them in our wiki or articles section with credit. But I have a high standard for such articles....one of them being they have to be fairly timeless (accurate for years).

 

[smwilliamson]

I know I've had a few customers email pics in last year but I can't seem to find them. Where I have seen this to be most common is with the Quadrafire Mt Vernon Stoves. There is a Fasco replacement that works well with it but the blade design is different from the original. I've also had some Kozi users ask about it being different. It's not a real common problem but last year I had a lot of people have questions about it.

I'm guessing that your customers are noticing a difference and are skeptical that the motor you sent them is actually a factory listed part. Though it may be...I have seen your eBay store and you have all kinds of parts you're switching around for this and that.

Lastly...what have YOU noticed about the motors? What say you there PRO? "

"Justanswer" us.

 

[DexterDay]

There is a difference in the fan blades and there have been tests done in them.

AES actually uses your "large fan blade" style you speak of as there "High flow" impeller (Old to you and not a good choice). The "New fan blade" is actually there low flow model (your newer model).

The old ones have a higher air flow, so yea, they may strain the motors some. But my old Englander went about 14 yrs before the motor blew. Just sayin..

Also, there are many variations in the fan blade, some are double sided for high elevation. And high EVL applications.

Info on blowers is out there. Site the place where your info comes from.

Trolling.......