Hearthstone Heritage stove creates a lot of black soot

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New Member
Nov 11, 2023
The issue is when I run it on low, the inside of the stove gets covered in black soot. Running it on high fixes the problem, soot wise, but makes the house too hot. It’s direct vented to the outside with about 4 feet(total) of horizontal run and 4 feet of vertical rise. There is an OAK installed.
My question is, can I change some of the control settings (combustion fan, room fan, auger speed, etc) to run the stove on low and mitigate the sooting? What settings should I choose? Thanks for any help. I have contemplated getting a smaller stove, but would like to attempt at making this one work.
What is the Moisture Content of your wood?
According to the manual, your chimney is about 9 FEET too short…

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{{{Quote According to the manual, your chimney is about 9 FEET too short}}} I don't see that as an issue at all???? :rolleyes: What size pipe are you running?? Also Is your pipe free of Flyash???----------------https://hearthstonetech.com/wp-content/uploads/2020/12/hearthstone-heritage-8090-manual.pdf------- air to fuel ratio adjustment pdf posted below----------------------------------------------------------------------- From the Manual Venting Warning: Ensure your venting system (chimney connector, and chimney) are in good condition and kept clean. The minimum horizontal clearance to vegetation and other exterior combustibles such as mulch is 36” asmeasured from the center of the outlet or termination cap. This 36” radius continues to grade up to a minimumof 7 feet below the outlet.The longer the vent pipe and more elbows used in the system, the greater the flow resistance. Therefore, we recommend using as few elbows as possible, and 15 feet or less, of vertical vent pipe. {{The maximum horizontalrun should not exceed 10 feet.}} If more than 15 feet of pipe, or two 90° elbows are required, vent pipe sizeshould increase to 4”, as larger piping offers less flow resistance. Maximum recommended vertical vent for 4inch pipe is 30 feet.Please note that pellets are a wood product and soot may occur during startup while the firebox approachessufficient temperature to sustain complete combustion of fuel.Soot and Flyash: Formation and Need for Removal- The products of combustion will contain small particles offlyash. The flyash will collect in the exhaust venting system and restrict the flow of the flue gases. Incompletecombustion, such as occurs during startup, shutdown, or incorrect operation of the room heater will lead tosome soot formation which will collect in the exhaust venting system. The exhaust venting system should beinspected at least once every year to determine if cleaning is necessary. To reduce the risk of a chimney fire,remove any soot or flyash if an accumulation of 1/8” (3mm) or more is found.Your Hearthstone appliance can handle up to 10 feet or equivalent of horizontal venting. Please follow ventingmanufacturer’s recommendations and required installation procedures. All joints for connector pipe shall berequired to be fastened with at least three screws. If vented horizontally, joints shall be made gastight with atleast three screws and high temperature silicone.Before considering your installation to be complete, perform a leak test on your venting. Leaks are easiest tosee during startup. Look for leaks at the vent pipe joints. Use of an incense stick is recommended to find leaks.Though unlikely with pellet burning appliances, incomplete combustion of biofuels can produce CarbonMonoxide (CO) which is a colorless, odorless gas. Exposure to high concentrations of Carbon Monoxide canresult in injury or death. Install a CO detector (recommended), and keep your appliance and venting maintainedaccording to the instructions in this manual.Important: Use all specified components and methods for the installation. Do not use componentsthat are not specified in this manual. Failure to use specified components and methods could voidyour warranty, and can cause malfunction or damage to the unit or structure.Do not modify the appliance to accomplish installation. Any modifications will void your warranty. https://hearthstonetech.com/wp-cont...-pellet-8330-air-to-fuel-ratio-adjustment.pdf
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Hello, thanks for replying. I am not sure about the moisture content of my pellets , but they are considered a high quality soft wood(Vermont Wood Pellet Co.) My chimney is 3” and has 3 feet of horizontal run out the back of the stove through the wall, a clean out T, vertical for 4 feet, 90 degree elbow, then 2 more feet of horizontal ending with a cap. I am very thorough with my cleaning , since these stoves are particular about that. Could changing the venting configuration help to prevent the sooting?