Add speed control to old EF2 exhaust blower?

Many if not most stoves have a way to trim the exhaust blower. My old EF2 does not, it relies on a damper. The damper does seem to function as designed, and closes to almost fully closed, about 1/4" open. Still, the stove is almost never within spec on the draft reading. The manual says with a .12-.13" on a high fire setting. I can sometimes get close to that, but more often I'm higher, sometimes at almost .2" My vent has a lot of natural draft to it. If there's a power outage, no smoke at all enters the house.

So here's my thought: I'm considering adding a motor speed control and using it fine-tune the draft. The blower is a newer motor that is adjustable.

The upside is I would be able to tone down the fire when it gets kind of blow-torchy on those real cold days when that 15' insulated vent makes the stove draft more. The con's are I would be introducing one more part to the stove that could fail. Of course, the vac switch would still be in place as well as the over-temp snap switch.

The other option would be to upgrade to the newer control board, which adjusts blower speed to match other settings. I don't plan to do that. I am quite fond of the simplistic, inexpensive analog controls that are cheap and easy to understand and troubleshoot.

Any feedback? Recommendations for a robust motor control?

 

Adding a triac speed control is a simple maneuver, just cut the L1 line to the fan and insert the controller.

Most casablanca fan controls will do the trick fine

DO NOT USE a light dimmer, as they are not rated for the load and may not produce a clean enough wave form.

The digital control boards that control the draft fan based on fuel feed settings are OK
BUTTTTTTTT, these are designed for (No insults intended) the average village idiot that has no clue about draft fans, Water column readings or possibly barely understands having to put pellets in the stove hopper.

If you want to hand tweak the thing you can get it right into the sweet spot.

Have fun

Snowy

 

My Adv 2 T has a triac in the draft fan speed circuit and varies the fan speed with fuel feed setting, but it has failed in the near full speed mode.

For our application the current fan speed it dandy.

I intend to install a triac in my new panel setup so I can do exactly what you propose.

I may use a speed controller that allows fixed settings on the draft fan.
Maybe 3 different speeds. ?????? Not sure yet.

I don't want a knob that can be moved by accident and turned too high or off

 

Thanks! I did order the part. It'll be good to get the burn just right on those real cold nights when that vent wants to draft like crazy. Maybe I'll even hang the gauge right on the back of the stove, semi-permanent install. That way I'll get the added benefit of having to say "no" when my neighbor wants to borrow it. (just kidding, he's a nice guy)

 

Snowy, to your point: we have a town Facebook page, and I often see requests where people are looking to hire "someone to clean my pellet stove." Not "install," not "repair," but "clean." I know it's not unusual, but it drives me nuts.

 

bcarton

I have seen those sorts.

Gawd, do they need someone to wash their toilet too ????

I view cleaning the stove as a privilege, sort of a right of passage to be allowed to own and care for the fine little creature that keeps me warm all winter.

I want to have INTIMATE knowledge of every part of the little beast.

On that cold dark night when its going sideways and the stove quits, I want to be able to pull tricks from the magic tool box and gitter burnin again quickly.

Hire someone to clean the stove, gawd, get a life eh ???


Thanks for sharing that one

 

This works perfect.
Do it all the time with your over blowy Yanky stoves.
Like Snowy says use a ceiling fan controller not a light dimmer.
Cost me about $10 and works a treat.
On Santa Fes I put one on the room air blower as well otherwise they are good dam noisy.

I have found on the Enviros it is not even necessary to go that far. Just tape up the air intake to choke off the air supply. Check out this video I prepared ear;ier showing an EF2 (I think) running on olive pits....

 

Any motor is adjustable with the fan speed controller. You dont need a big one, just one of those click through the wall plate jobs, 10 bucks like I said. You can see from the video that the air intake is almost completely closed. This is testament to how leaky the EF2 is. Doesn't matter though, once it is tuned right it will run sweet like here. I sold the stove in the video over a year ago and the new guy has put nearly 4 ton of the pits through it with that bit of tape still over the intake. Still running sweet. No fan potentiometer switch at all, just the tape.