Whitfield Prodigy 2 Exhaust Issues

[Bob P.]

Hi,
New to the forum, just purchased a prodigy 2 cleaned it an fired it off yesterday. The exhaust booster fan is wired for variable speed and needs replaced. It has a lot of play and drag in the armature although it still turns, it won't come up to full speed and big time vibrates. Couple of questions, Should I run my exhaust fan at line voltage or slaved to the blower? Mine is wired to run variable with the blower and am thinking of wiring it to run at full speed continuously. Thoughts?

Second question although kind of related. One of the reasons the guy sold the stove was that it kept throwing a high limit snap located at the back of the feeder tube and he saw smoke in the hopper. I watched it yesterday and it threw a high snap when it got low on pellets. I was watching the action of the flame on 5 and when the pellets got low enough to barely expose the auger inside the hopper, I noticed some smoke coming out of the bottom of the feed tube in the hopper. This is also when the the exhaust fan was struggling to run I'm going to say it was at quarter to half speed. By replacing this fan, will it create enough negative pressure to prevent the flame from pushing into the tube or do you think I may have another issue understanding that proper draft is key?? I have a separate big E pellet stove in my garage and the hopper cover has a gasket on it, must stay closed during operation and is switch protected to kill the auger when opened so that flames cant push there way up the feed tube finding another path to exhaust and ignite the pellets in the hopper. My Prodigy is not that way. No sealed hopper so when it gets low enough on pellets, it creates a clear enough path for the stove to find another means of exhaust which is through the tube heating it to the point the high LS opens and kills the blower just before the stove runs out of pellets.

Am I on base with this and has anyone seen this in their stove? I really like the stove and it is in very good shape however, I dont want to put this in my house thinking its not burning right or having it keep overheating.

Thanks and Merry Christmas,
Bob

Ignore the shiny pipe. I just used it to fire it off.

 

[DirtyDave]

well i would replace exhaust fan if it is struggling and there is no plugging of exhaust from ash.

 

[Bob P.]

Yes, exhaust is clear. I took the top of the manifold off and did a thorough cleaning, replaced the gasket and had to make new mounting plate/shroud for the exhaust fan (you can see it in the photo). The old ones holes were relocated and stripped multiple times to the point the motor had nothing to attach to. Waiting on a new motor for the fan and then I will see how the new one runs comparatively and vents the stove.

Any thoughts on running the exhaust fan slaved, or at full line voltage? How does the advantage's exhaust work? I have positive pressure from the blower/squirrel cage for the combustion and heated air. My exhaust fan operates at variable speed based on my heat setting via the control panel. I'm not too fond of the set-up of the exhaust fan....Long shaft from the armature that the fan blades mount to. the shaft is 4 inches long and two impellers mount to it. one motor cooling fan about a half an inch away from the bearing that you see in the pic. and another inside the exhaust housing which is about 3 inches away. seems like it's a high maintenance item to keep from vibrating. I thought about designing and adapting a different variable speed fan that would mount to my exhaust port much like a power vent unit but I will wait until I see how this one performs.

Ever have any problems with your high limit or flames wicking into your feed tube? I'm thinking it's an exhaust issue. Without the fan running at speed and virtually no vertical draft, I think the exhaust and flame were looking for any place to escape...

I just sent a guy a message on craigslist about a Whitfield he is looking to get rid of because the control board is acting up (not sure what model). I'd like to get it for cheap and do all of the controls and safeties with mechanical devices readily available from our HVAC dealer. Be a nice little project.

How do you like your Advantage?

Bob

 

[DirtyDave]

I love my old stove

 

[Snowy Rivers]

Hi

Been away for while.

Yessssss, replace the exhaust fan assembly (motor and all) with a new one.

One of our vendors offers these.

Get the entire exhaust casting out and apart.

Clean out the entire area and remove the fan and motor.

Be careful when you reinstall the casting.

Use new flat seal rope and silicone it to the housing in the stove and then sit the fan assembly onto the rope dry.

Tap the two front holes on the little ears that pull the housing forward and use two new allen screws and toss the old self tapping ones.

When replacing the casting, slide a thin piece of sheet metal in alongside the white insulation on the side opposite the fan motor.

This makes it easy to get the casting back in.

Once the fan casting is in, slide the sheet metal out.

With the casting sitting in the stove, lightly snug the 4 top bolts (finger tight only)

Now snug the two front allen bolts to cinch the casting into the angled flange on the lower sheet metal.

With things snugged forward, then snug down the top 4 bolts and then tighten.

The four top bolts and threaded into heavy sheet metal and can not take real hard tightening, so go easy.

The exhaust fan should run at full speed.

Depending on the ser### the stove can be wired several ways.

The stove I have has full power to the exhaust fan,and the feed setting controls the combination room air/combustion fan speed.

With things all clean inside (you will be able to really do this once the top is off) the little Whit is a great stove.

Get a service manual and it covers all the wiring oddities.

Same vendor has the books (downloadable pdf) that sells the fans/motors

Snowy

 

[Snowy Rivers]

Here are some pix of mine while it was apart.

A note here, the two ears on the front of the casting are not real hefty, so don't get wild when snugging up the two bolts.

You will see how the entire setup works once you get yours apart.

After you silicone the new rope seal to the metal housing in the stove, let it cure before installing the casting back on.

Make sure your rope is long enough and trim it at the last minute.

Make your joint at the front and not near any of the bends.

Be sure to silicone the joint well so once it's assembled it does not leak smoke.

After the silicone is cured, the assembly is easy and pretty straight forward.

Cutting the wires to the motor and crimping on bullet connectors makes it easy to swap the motor.

The new motor comes with a larger diameter shaft and a slightly different fan, but it fits perfect.

The original fan motor had a 1/4 inch shaft, the new one is 5/16.

Make sure that once the fan is all installed that the shaft turns freely and does not bind in the casting.

Just a note.

Once the top is off, the bottom of the housing comes off to allow access to the fan compartment.

Clean the entire cavity real well as the vent through to the fan cavity is small.

My stove was totally choked with crud when I dug into it.

Good luck

Snowy

 

[Bob P.]

Good to see you back... must be a prodigy thing.

Advice taken. I was thinking about building an external exhaust blower but if yours runs good with the new fan, then that's good enough for me.... and less work... I will get one on order.

The prodigy is running right now but the exhaust fan is sluggish and when it gets to about 3/4 full speed, it vibrates like crazy. I had it apart when I first got it a few weeks ago, did a thorough cleaning and checked everything out. The booster fan was attached with one screw and all the others were stripped and had multiple holes so I had to make a new exhaust fan mounting plate. The bearings on the C-frame motor are giving some play and it doesn't take much to allow the impeller that's 4 inches away to start to vibrate ( 1/4 inch shaft )

I did have the top off the manifold and will take it off again. I like the advice on tapping and installing new screws on the ears.

I like this little stove. Serial no. 2609 with the hall effect blower. I'm getting some bearing noise from it though. I think if it goes, I will eliminate the circuit board and do something like your diagram you had in one of your posts.

Did you ever engineer everything to fit where the control panel is?

How's your glass on your prodigy and how long before you can't see the flame? Mine is black as the ace of spades. I'm pretty sure I'm not getting enough draw on the exhaust side to make the stove work properly so as soon as I get the booster fan in, I will see how it works.

Next question: Any history with the Whit Quest Plus?? Just picked one up on Tuesday. Tore it down, cleaned and lubed everything and fired it off. Here's a couple pictures..


Nice looking hunter green stove in great shape(after the cleaning) Needs a new cera board.

This stove has a large bottom grated burn pot and about an inch and a half square metal chase that sits below it where the combustion air is able to be drawn from by the exhaust motor. This square chase extends about 6 inches back from below the fire pot and has a hole on the side facing away from the conv. fan. When the convection blower runs at 4 or 5 speed, it draws ash and or pellet fines through this hole, sucks them up the squirrel cage and out of the tubes into the room. (just my garage for now) too much conv. fan or am I missing something. even if I have the exh. blower on 5 and the fan on 5 it does it.

It's like the convection blower motor is too powerful and the squirrel cage faces the center of the stove pulling from what is suppose to be the air supply for the pot. Strange.

By any chance know how far I should be able to damper this stove down?? Freed up the damper that was frozen from not being moved when cleaning and it looked like there was a metal stop that prevented the damper from closing all the way. It leaves the damper about 2 inches open which is still jumping my pellets all around even with the comb. blower trimmed way back.

Quiet stove though.

I didn't mean to get long winded and any advice is appreciated. I will get some pictures this weekend and post them to get a better idea of what I'm looking at in case your not familiar with that model.

Thanks Snowy, Good to have people like you on this forum.

Bob

 

[Bob P.]

Found the origin of my particles on the quest plus.

Stove running, no fire, still blowing small pellet particles and the occasional black particle above the tubes where it has a small maybe 1/2 inch cavity that blows as well. (be nice to get a diagram on what the inside of the heat exchanger cavity looks like.)

Took off the sides, conv. blower and spent some time with smoke and mirrors (literally) finally hit one of the tubes with air and pushed out a considerable amount of this debris through the top cavity.
Used various sized rubber hoses in all of the tubes and through the exchanger and into the back of the box until I chased all of them out. Turned out to be pellet particles mixed with some small hard black debris.

Go figure.. the particles that I was seeing coming out of the draft inlet while watching the stove run with a 300 watt light were being blown from inside of the heat exch. box, through a small gap next to the auger tube ricocheting off of the exhaust mounting bracket and laying next to the opening on the inlet tube every 10 to 20 seconds or so.

This stove is purring like a kitten right now..... much quieter than the prodigy but will see once I get the new exhaust fan in, still going to have the bearing "whish" on the conv/comb. blower motor though. I hit it with some 3 and 1 and seems louder... might be me.

Bob

I enjoy figuring these older stoves out as a hobby and I really like these two Whitfields that I have and might want to try an advantage or get an older Harmon to bring back to life. that I have. Much