Enviro Mini to Mini-A Upgrade - New Control Board and Burn Pot/Liner

[LI-Mini-Owner]

I was considering a control board upgrade on my early model Mini ( see https://www.hearth.com/talk/threads/50061/ ), but decided to upgrade a few other items as well.

I had a great phone call with an Enviro Factory Tech, and based on his recommendation I opted for the new board and larger burn pot/liner. It was expensive, but the original setup was so problem prone that I figured it was worth it, since I plan on using the stove another 10 years. Installation was easy, and after two days I can say that my new Mini-A is workring great.

My problem had always been that about 10% of the pellets would immediately pop out of the burn pot onto the grate. Closing the damper down reduced the popping, but yielded a sluggish flame. Also the original control board lacked trim controls for combustion blower and auger feed rate. This made it very hard to keep a low-flame going with most of the pellet brands I tried. It also lacked a thermostat mode switch. The hi/low vs on/off mode was selected with a jumper on the board. I did wire an external switch, but the stove needed to be shut down and unplugged for the mode change to take affect. All resolved with the new board. The on/off mode now kick down to low for 30 minutes before shutting down. If the thermostat calls for heat again withing 30 minutes it kicks back up to high. This will reduce stove startup cycles.

I would recommend this upgrade for any Mini owners that have had similar problems, even if you go with just the larger burn pot/liner. Here are the part numbers I used (Note: These are new part numbers provided by the Tech that don't appear on even the latest Mini-A manual that I downloaded).

50-1929 - Control Board - $298 -
50-1931 - Control Board Mounting Panel and Decal $26
50-1922 - Mini-A Burn Pot - $57
50-1923 - Mini-A Burn Pot Liner $76 (needed to file down a weld-blob on bottom to make it fit - no big deal)

Note that they also sell a new right side stove cover that I did not opt for. With the original cover a couple of LED's are partially obscured, but it's 100% usable.

Here are some pix.
1. Old vs new larger burn pot size comparison
2. New control panel decal showing top two LEDs partially obscured (Heat level 5 light and pulsing auger light).
3. Happy new flame.

 

[jtakeman]

Very nice write up and should help several mini owners. Will make that older mini perform like the newer upgraded mini's.

Great work
jay

 

[hoverfly]

That's great news, mine was manufactured in 2008 biggest gripe I have with it is lack of combustion blower control between high and low settings. Unfortunately this is a upgrade that will only be able to funded (over five hundred bucks.......!! Ouch!) some time before next winter. I did go to my dealer and checked out the Mini A, and looked at the changes. I might just buy the control board and decal first to see if that works since it looks like my original pot is biger than the much earlier modals.

 

[LI-Mini-Owner]

One more thing... When upgrading to the larger burn pot you need to remove and discard the old "burn pot bottom" (the piece that slides in/out under the burn pot.) Not sure how much air will now leak into the stove from where the slide handle protruded. May consider a little hi-temp silicone to seal.

 

[hoverfly]

One more thing... When upgrading to the larger burn pot you need to remove and discard the old "burn pot bottom" (the piece that slides in/out under the burn pot.) Not sure how much air will now leak into the stove from where the slide handle protruded. May consider a little hi-temp silicone to seal.

Could you post a before and after photos of the burn pots? Maybe a new piece of steal cut out to cover the opening would work?

 

[LI-Mini-Owner]

One more thing... When upgrading to the larger burn pot you need to remove and discard the old "burn pot bottom" (the piece that slides in/out under the burn pot.) Not sure how much air will now leak into the stove from where the slide handle protruded. May consider a little hi-temp silicone to seal.

Could you post a before and after photos of the burn pots? Maybe a new piece of steal cut out to cover the opening would work?

The old burn pot liner is open on the bottom. Here is a pix of the old sliding bottom plate that needs to be removed as part of the install. That leaves a rectangular hole in the grate. The new pot liner has an integral bottom welded on (it's not open like the old one). It completely covers the rectangular opening in the grate.

Carl

 

[hoverfly]

OIC thanks

 

[henryb]

Interesting post, thanks. Some questions: Does the larger burn pot buy you anything? Does the new board do anything if I'm not using thermostat control?

 

[jtakeman]

Interesting post, thanks. Some questions: Does the larger burn pot buy you anything? Does the new board do anything if I'm not using thermostat control?

My take on the large pot is less chance of clogging. Improved air flow for a better burn.

My take on the control board is more control over the burn. You will have auger trim in all 5 settings, Giving you 25 different heat settings(same as my Omega). And Combustion blower trim which should help in adjusting the flame quality(I wish my Omega had this). Combustion trim is a finer adjustment than the draft rod. It varies the blower voltage so you can increase or decrease draft without moving the damper rod. A lot more tweaking tools for adjusting for different pellet qualities.

 

[LI-Mini-Owner]

Yup - Jay covered the main points. The larger burn pot also catches 100% of the pellets. Prior to that, depending on the brand of pellets 10 to 15% of them would get deflected by the combustion flow, and land on the grate instead of in the pot, where they would just smolder.