Harman ignitor staying on (unless door is opened)

[MapleHill]

Last winter, my Harman 52i burn pot bubbled and cracked, which I attributed to age and use. I recently replaced the burn pot and also just so happened to use an energy monitor on the pellet stove. What I found was that the ignitor is staying on even after the fire is lit (which can lead to a bubbled burn pot and high energy use). By the way, this also has the stove running for much longer after the fire is out, because the firebox is still "warm" from the ignitor!

So, I just ran some tests. The ignitor is coming on and staying on anytime the stove is on. Even in "manual" ignition mode (!). However, the ignitor goes off if the door is opened. Once the door closes, it's back on again.

Before I go chucking more parts at this thing, does this sound like a board problem or a short on the ignitor itself? Thanks everyone.

 

[jzm2cc]

Control board problem. Triac (AC switch of sorts) is shorted internally more than likely and keeping the igniter powered.

 

[jzm2cc]

If you are handy with a multi-meter and solder iron it can be replaced independent if the board. It should be one o

f the 4 little black devices shown in pic. Comparing resistances between pins and between each other should reveal the shorted triac.

 

[MapleHill]

Thanks very much for that tip! I have been known to fire up a soldering iron from time to time so I'm going to give that a try.

In the meantime I have a new board on the way. If I'm able to fix the triac, that can be my backup board. I appreciate the info!

 

[jzm2cc]

Very welcome. If you can trace the igniter circuit to the appropriate board connector pin, then the multi-meter will identify the correct triac once you see near 0 ohms on one of the pins. I assume you'll see low resistance on the Drain and Source pins compared to surrounding triacs. Looking up the chip part number on google should reveal a schematic showing the pin identification. Good luck.