Vermont Casting 1990 installation instructions Draft Management

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Intrepid II Woodburning Stove

Draft Management

A stove is part of a system, which includes the chimney, the operator, the fuel, and the home. The other parts of the system will affect how well the stove works. When there is a good match between all the parts, the system works well.

Wood stove operation depends on natural (unforced) draft. Natural draft occurs when the smoke is hotter (and therefore lighter) than the outdoor air at the top of the chimney. The bigger the temperature difference, the stronger the draft. As the smoke rises from the chimney it provides suction or ‘draw’ that pulls air into the stove for combustion. A slow, lazy fire with the stove’s air inlet fully open indicates a weak draft. A brisk fire, supported only by air entering the stove through the normal inlet, indicates a good draft. The stove’s air inlet is passive; it regulates how much air can enter the stove, but it doesn’t move air into it.

Depending on the features of your installation - steel or masonry chimney, inside or outside the house, matched to the stove’s outlet or oversized - your system may warm up quickly, or it may take a while to warm up and operate well. With an ‘airtight’ stove, one which restricts the amount of air getting into the firebox, the chimney must keep the smoke warm all the way to the outdoors. Some chimneys do this better than others. Here’s a list of features and their effects.

Masonry Chimney

Masonry is a traditional material for chimneys, but it can perform poorly when it serves an ‘airtight’ stove. Masonry is a very effective ‘heat sink’ - it absorbs a lot of heat. It can cool the smoke enough to diminish draft. The bigger the chimney, the longer it takes to warm up. It’s often very difficult to warm up an outdoor masonry chimney, especially an oversized one, and keep it warm enough to maintain an adequate draft.

Steel Chimney

Most factory-made steel chimneys have a layer of in- sulation around the inner flue. This insulation keeps the smoke warm. The insulation is less dense than mason- ry, so the inner steel liner warms up more quickly than a masonry chimney. Steel doesn’t have the good looks of masonry, but it performs much better.

Indoor/Outdoor location

Because the chimney must keep the smoke warm, it’s best to locate it inside the house. This uses the house as insulation for the flue and allows a little heat release into the home. An indoor chimney won’t lose its heat to the outdoors, so it takes less heat from the stove to get it warm and keep it warm.

Flue sizing

The inside size of a chimney for an ‘airtight’ stove should match the size of the stove’s flue outlet. When a chimney serves an airtight, more is not better; in fact, it can be a disadvantage. Hot gases cool off through expansion; if we vent a stove with a six-inch flue collar (28 square inch area) into a 10 x 10” flue, the gases expand to over three times their original size. This cools the gases, which weakens draft strength. If an over- sized flue is also outside the house, the heat it absorbs gets transferred to the outdoor air and the flue usually stays cool.

It’s common for a masonry flue, especially one built for a fireplace, to be oversized for an airtight stove. It can take quite a while to warm up such a flue, and the re- sults can be disappointing. The best solution to an over- sized flue is an insulated steel chimney liner, the same diameter as the stove or insert’s flue outlet; the liner keeps the smoke at its original volume, and the result is a stronger draft. An uninsulated liner is a second choice

-the liner keeps the smoke restricted to its original size, but the smoke still must warm up the air around the liner. This makes the warm-up process take longer.

Pipe & Chimney Layout

Every turn the smoke must take in its travel from the stove to the chimney top will slow it down. The ideal pipe and chimney layout is straight up from the stove, to a completely straight chimney. If you’re starting from scratch, use this layout if possible. If the stove- pipe must elbow to enter a chimney, locate the thimble about midway between the stove top and the ceiling. This achieves several goals: it lets the smoke speed up before it must turn, it leaves some pipe in the room for heat transfer, and it gives you long-term flexibility for installing a taller stove without relocating the thimble.

There should be no more than eight feet of single-wall stove pipe between the stove and a chimney; longer runs can cool the smoke enough to cause draft and creosote problems. Use double-wall stove pipe for long runs.

Single Venting

Each ‘airtight’ stove requires its own flue. If an airtight stove is vented to a flue that also serves an open fire- place, or a leakier stove, it’s easier for the chimney draft to pull air in through those channels than it is to pull air through the airtight, and performance suffers. Imagine a vacuum cleaner with a hole in the hose to see the ef- fect here. In some cases the other appliance can even cause a negative draft through the airtight, and result in a dangerous draft reversal.

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Contents Intrepid Welcome Table of ContentsIntrepid II, Model SpecificationsOutside Air InstallationWhat Kind of Chimney to Use Masonry Chimneys Chimney Connector GuidelinesPrefabricated Chimneys Chimney SizeSingle-wall Chimney Connector Double-wall Chimney ConnectorSecuring the Single-wall Connector to a Masonry Chimney Freestanding Chimney InstallationsChimney connector enters chimney above the firep Fireplace Chimney Installations Above a FireplaceWall Pass-Throughs Fireplace Chimney Installations Through a FireplaceAn approved wall pass-through for Canada Floor ProtectionReducing Clearances Floor Protection for Fireplace InstallationsStove Heat Shields Chimney Connector Clearance ReductionsWall Shields Fireplace and Mantel Trim ShieldsConstruction Requirements Alcove InstallationsReflected ceiling plan Intrepid II Clearance Chart Intrepid II Clearance Diagrams 889 mm Parallel Installations Assembly Attach the Griddle Handle OperationYour Intrepid II’s Controls What They Do Glass Door Panels Damper Directs Air Flow Within the StoveAndirons Two Ways to Add FuelSurface Thermometer is a Valuable Guide to Operation Burn Only High-Quality WoodHow to Build a Wood Fire Keep it Going Use the Air Control Settings that Work Best for YouHigh-Efficiency Wood Burning With Catalytic Combustion Starting and Maintaining a Wood Fire Conditioning Your StoveAsh Disposal Refuel While the Embers are Still HotDraft Management Creosote Draft TestingFuel Back-puffingMaintenance Damper Adjustment How to Adjust the Door LatchTighten the Damper Handle as Needed When to Suspect a Combustion System Problem Catalytic Combustion System Inspection and CleaningReplace the Stove Gaskets as Needed Replace Refractory PackageAnnual Maintenance Adjust the Door if NecessaryPermanent Gaskets Chimney System CreosoteIntrepid II Woodburning Stove Appendix Catalytic Combustor Intrepid II Woodburning Stove Intrepid II Woodburning Stove Please record the following information For future reference Intrepid II Woodburning Stove Intrepid II Woodburning Stove Warranty CFM Corporation

1990 specifications

Vermont Casting, founded in 1975, is renowned for its commitment to crafting high-quality cast iron wood stoves and heaters that merge efficiency with timeless design. By 1990, Vermont Casting had established itself as a leader in the industry, celebrated for its innovative approach to heating solutions and commitment to sustainability.

The 1990 models reflected an impressive evolution in technology and aesthetics. One of the standout features of Vermont Casting stoves was their utilization of advanced air control systems. This technology allowed users to regulate the burn speed and heat output effectively, making it easier to maintain consistent warmth in the home while optimizing fuel efficiency. The stoves featured an adjustable air inlet that provided users with the power to control combustion according to their needs.

In terms of design, Vermont Casting stoves were characterized by their iconic, rustic appearance, often featuring a choice of colors and finishes that allowed them to blend seamlessly into a variety of home aesthetics. The deep, rich finishes of the cast iron, coupled with elegant detailing, made each unit not only a heating appliance but also a centerpiece in living spaces. This commitment to aesthetics extended to the variety of designs available, including both traditional and modern styles, catering to diverse consumer preferences.

Vermont Casting also prioritized safety in their 1990 models. Many stoves were equipped with features such as double doors with glass panels, allowing users to enjoy the beauty of the flames while minimizing the risk of accidental burns. Some models incorporated heat shields that protected surrounding walls and furniture from excessive heat, further enhancing safety at home.

Durability was another hallmark of Vermont Casting’s reputation. The use of high-quality cast iron meant that these stoves were built to withstand years of use, often becoming familial heirlooms passed down through generations. In addition to resilience, cast iron was known for its ability to retain heat even after the fire had gone out, providing lingering warmth long into the night.

Overall, Vermont Casting in 1990 represented a harmonious blend of timeless design, advanced functionality, and a commitment to sustainability. Their stoves were not merely heating appliances but symbols of a lifestyle choice that emphasized quality, elegance, and environmental responsibility, making them a preferred choice for homeowners seeking both reliability and beauty in home heating solutions.
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