Fireplace/Chimmney question?

Hello all, I’ve got a fireplace insert/heater that I’ve just started using for the first time since I bought the home, it was installed who knows way back when in my basement fireplace. The question I have is even though it seems to work awesome I’m seeing lots of dark staining like black or brown water stains running down from my chimmney cap. the wood being burned is silver maple that was cut about 3 years ago and has been stacked under my deck. The make of the insert is a “Nordic” and the Model is an “Erik”

Does anybody have any ideas about whats going on? or how to stop that mess coming out of the chimmney?

Thanks in advance for any ideas and input.

Tom

I don’t know but is it the type of wood your burning?

Sounds like a good time to call a chimney sweep and have it cleaned and inspected, especially considering it hasn’t been used in an extended period.

dried silver maple

It was cleaned slick as a whistle just before I bought the house and I saw the reciept, and when I performed maint on the cap summer before last i got a great look and it was clean, I just don’t know enough about wood burning I guess.

Hard to diagnose, do you have a pic?

I’m guessing but maybe what you’re seeing is a combination of smoke and water (condensation)? The chimney cap would be a likely spot for that to occur.

I don’t know how to put up a picture here, but after a few exhausting hours scouring the internets : D, I found out Karry is right, also found out that it’s easier for creasote to build up if you run a low fire, this unit has dampers on it that allow wood to burn all day depending on your settings. Also when I performed that maint on the cap I used chimney RX product and its a grey cement color and the stains are much more easily seen.

It looks like I’ll have to run a good fire more often and longer, use a creasote buster log or product a few times during the season, and clean it every year.

The locals up at the cabin that heat with wood will tell you that they burn seasoned hardwood and through poplar every so often. It burns hotter and keeps the creosote from building up.

You maybe want to burn a hot fire for a couple hours every other day or so while using the fireplace and the maple. Oak burns hot and won’t create so much creosote in the pipes. If you’re looking to fire this up and use it as an all day supplement to your heating furnace I’d suggest getting seasoned oak.

As mentioned, too low of heat and it’s condensation. Stoke up some more

A huge thanks to you guys, once again you all got me dialed in, the knowledge on this site is incredible.

I’d like to wish everyone on this site a Merry Christmas and a Happy New Year. Now its time to finish packing for the trip to Park Rapids and LOTW tomorrow morning : )

Tom

Get something on it you can measure temp with if possible. I like to have a nice roaring fire and keep it above 600 for at least an hour every other day. What you are seeing is the sign of a cool fire for too long.

tom:

All firewood, dry included still has moisture in it. So in the burning process the first part of the burn with fresh wood on the fire is going to burn the water out of the log. If you keep an eye on the ends of the wood you’re burning you’ll get an idea of how wet each log is. The goal is to be burning at a higher heat at this time keeps the cap above 212 degrees so the water vapor escapes the cap without condensing on it. Once it appears the woods has lost most of its moisture you can burn it slower at the lower heat cause most of the water is gone.

I don’t have much of a creosote issue and typically burn seasoned oak/birch.

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EP Guy:

Absolutely correct!!! Burning that hot at the firebox should enable the entire piping from the firebox all the way to the very top/cap should be able to stay at the or above 212 degrees, which is hot enough to emit any of the moisture that could be traveling up the pipe That’s the reason to burn hot!!! Once your wood ends show that the moisture is burned out of them, then you can slow the fire down and leave it at a slow roll. But each time you reload the fire box with new wood, you need to watch those ends to see what moisture is coming out of the ends.

Mark

P.S. > Oak, well seasoned is a great wood to burn asd it holds the highest BTU ratings of our northern hardwoods. One of the things I learned about oak is that it takes two to three years of constant drying under full roof to become that perfect seasoned. If it gets wet, it WILL reabsorb that water, so it needs to be taken care of.

That birch will generally dry well if it’s like popple, split right away and not allowed to rot inside the bark. It will burn hot even though it doewsn’t hagh a high BTU level.

mbenson, a bi product of combustion is water vapor even with LP gas

Jeremy:

True story… gas stoves that decide not to burn at the top of the piping (especially 30’+ runs to the peak) are often frosted/iced shut and can’t get enough combustion air back down to the pipe to be able to burn. If ya run into this problem, open the glass at the firebox to allow the gas flame to heat the box and pipe and melt the ice at the cap to get the proper amount of combustion air.

Our furnace is vented in the roof of our house as well and we had issues drawing combusiton air last winter with one of the bitter cold snaps…

Mark

My gas furnace has a short horizontal run to outside and has a different pipe for combustion air