Harman P35i - Rust in Firebox

[Mr. Heat Miser]

Today I had my first fire of the season in my Harman P35i pellet stove insert. This is my second season with this stove and it served me well last year, keeping me warm and toasty and cutting my oil use in half by burning just 2 tons. At the end of last season I gave the unit a thorough cleaning and disconnected it from the wall power for the Summer months. When I went to light it today I saw a few dead wasps in the ash pan, and when I opened the door before lighting it about 10 flies flew out into my living room. When I looked inside at the firebox, I noticed a significant amount of surface rust on the heat exchanger, burn pot and other surfaces. This is a fireplace insert unit with a quality chimney cap and a 4" stainless steel liner running up to the top of the chimney. I have not opened the pellet stove door since I shut it down and cleaned it at the end of last season. Obviously, the warm humid air from outside during the summer months came down the chimney liner (along with the bees and the flies) and into the firebox.

I was wondering if anyone else has seen this problem with rust in their firebox. I was thinking that it might be a good idea at the end of next season to block off the exhaust opening behind the ash pan with a rag or other means to make it air tight and to place a few desicant packs in the firebox to absorb any moisture that may enter from the interior side of my house. This would also stop the insects from making their way into the firebox. Obviously, I would make myself a big red flag note and place it near the stove to remind me to remove these items before lighting the stove for the first time next season.

Any thoughts or comments?

 

[newf lover]

Many people do that to avoid rust. Some spray a little Pam as well. It was an especially wet summer so that doesn't surprise me.

 

[SmokeyTheBear]

If your stove is where it can get exposed to warm moist air it will get surface rust. That is why a lot of us plug both our venting and OAKs, coat the interior surfaces of the fire box with a light oil Pam or wd-40 wipe it down and re coat it. Some folks clean and re paint their fire boxes. Then a good desiccant such as damp rid or silica gel is placed in the burn pot.

 

[Mike49024]

I have the same stove as you, bought mine a year ago, and put two tons though it last year as you did.

I did not have the bugs (dead or alive) that you did, however there was rust, nothing bad, just surface rust. A few fires later, the problem took care of itself. No worries.