Breckwell SW500 Wood Stove Size Guide

Under specific EPA test conditions, the SW500 has been shown to deliver heat at rates ranging from 10,652 to 26,028 BTU per hour at 1.7 g/hr particulate emissions and 75 percent efficiency. The manufacturer's BTU rating reflects the first hour of operation at high burn rate burning dry cordwood. Maximum log length 11 inches; firebox volume 0.59 cubic feet.

• Cabins, tiny houses, and small homes where the compact 13 inch deep by 16.4 inch wide pedestal footprint fits tight floor plans and 750 square feet is roughly the upper end of typical heating coverage.
• Off-grid installations without electrical service. The SW500 produces heat with no electrical input; only the optional B36T blower needs power.
• Power-outage backup heat for grid-tied homes. The SW500 continues burning regardless of grid status, providing reliable backup heat during outages.
• Garages, workshops, and accessory buildings with appropriate clearances and a UL 103 Type HT chimney installation.
• Additions, sunrooms, finished basements, and zone heating for rooms not well-served by the main HVAC system.
• Mobile homes and transportable buildings with the required outside air kit, factory-built UL 103 chimney, spark arrester, chassis grounding, and bolted floor mounting per the manual's mobile home installation requirements.
• Homes with existing 6 inch chimney systems from a prior wood stove that just need a stove replacement.

• Large homes or open-plan main living areas above 1,000 sq ft. The 0.59 cu ft firebox and 26,028 BTU upper output are sized for compact spaces; oversized rooms will not reach comfortable temperatures even at high burn. For larger spaces choose the Breckwell Big E pellet stove instead.
• Hands-off automatic heating. The SW500 requires manual fire building, periodic reloading, and damper adjustment. For automatic operation with optional thermostat control, choose the Big E.
• Alcove installations. The manual prohibits alcove installation.
• Factory-built fireplace installation. The SW500 must not be installed in a factory-built fireplace per the owner's manual.
• Hallways, near staircases, or sleeping rooms in mobile homes. Hallway placement blocks egress in case of fire; sleeping room installation in mobile homes is explicitly prohibited.
• Air distribution duct or system connections. The SW500 is not designed to be connected to any air distribution duct or central HVAC return.
• Burning fuels other than well-seasoned natural cordwood. Garbage, lawn clippings, plastic, treated wood, salt-water driftwood, painted wood, manufactured wax-impregnated logs, and unseasoned wood are all prohibited.

• Cold climate (Zone 5-7, design temperature 0°F or below): The SW500 fits cabins and small homes up to roughly 500-600 sq ft as primary heat in cold climates. For larger spaces in cold zones, use as zone heating for the most-used rooms.
• Moderate climate (Zone 4, design temperature 10-20°F): The SW500 reaches its rated 750 sq ft heating range in homes with average insulation. Most owners run the medium-high damper setting in cold weather and medium setting in shoulder seasons.
• Mild climate (Zone 3 and below, design temperature 30°F or above): The SW500 may heat up to 800 sq ft in well-insulated homes in mild climates. Most operation will be at low to medium damper settings.
• Cabins and tiny houses: The SW500 is well-suited for 200-600 sq ft cabin and tiny-house applications. The 11 inch log capacity means common firewood splits fit without recutting; the 0.59 cu ft firebox supports long burns at low damper settings.
• Cathedral ceilings and small open lofts: Heat stratification in tall spaces reduces effective heated floor area. The optional B36T blower significantly improves circulation; ceiling fans on low reverse-direction in winter also help.
• Drafty or poorly insulated cabins: Air sealing and basic insulation upgrades return more comfort per dollar than upsizing the stove. The SW500's 0.59 cu ft firebox is the practical upper limit for this product class; if more heat is needed, the building envelope must improve.

The table below reflects typical sizing recommendations under average insulation and 8 foot ceiling assumptions. Actual results depend on home insulation R-values, ceiling height, climate zone, layout connectivity, and air sealing. An NFI- or WETT-certified installer can evaluate your specific space and recommend a final sizing decision.

• No combustible material is permitted within 18 inches (458 mm) of the front of the unit.
• The clearance between the flue pipe and a wall is valid only for vertical walls and vertical flue pipe.
• The chimney connector must not pass through an attic or roof space, closet, similar concealed space, floor, or ceiling.
• Minimum floor-to-ceiling height: 7 feet (2.13 m).
• For Canadian installations, where passage through a wall or partition of combustible construction is desired, the installation must conform to CAN/CSA-B365.
• To reduce flue clearances from combustible materials, contact your local safety department.

The SW500 must have a non-combustible floor protector, UL 1618 listed or equal, with a minimum R-Value of 2.8 installed beneath it if the floor is constructed of combustible material. The floor protector must be large enough to extend under the stove and beyond each side as follows:

If there is a horizontal run of chimney connector pipe, floor protection must extend two inches beyond either side of the pipe. The SW500 is suitable for installation on a combustible floor without additional radiant floor protection where it meets the requirements of CAN/ULC-S627.

• Chimney connector diameter: 6 inches (153 mm) — same as the stove flue outlet.
• Chimney connector material: Black or blued steel rated 2,100°F (650°C). Minimum thickness 0.021 inches (0.53 mm). Galvanized steel is strictly forbidden.
• Connector installation: Male section (crimped end) facing down. Each section attached to the next with three metal screws spaced equally. Horizontal sections slope at least 1/4 inch per foot toward the chimney.
• Maximum connector run: Total length should not exceed 8 to 10 feet (2.4 to 3.04 m) to ensure good draft, except in cathedral-ceiling vertical installations.
• Maximum elbows: Never more than two 90 degree elbows in the smoke exhaust system.
• Damper restriction: Do not install a barometric draft stabilizer or fireplace register; flue damper installation is not recommended.
• Factory-built chimney: Must comply with UL 103 or CAN/ULC-S629 standard. Must be Type HT (2,100°F).
• Masonry chimney: Built to National Building Code specifications, lined with fire clay bricks, metal or clay tiles sealed with fire cement. Interior diameter identical to the stove smoke exhaust (6 inches). Round flues most efficient.
• Minimum chimney height: 12 feet (3.7 m). Must rise above the roof at least 3 feet (0.9 m) from the uppermost point of contact and exceed any obstruction within 10 feet (3.04 m) by 2 feet (0.6 m) — the 3/2/10 rule.
• Interior vs exterior chimney: Interior chimney installation always preferable — runs hotter, reduces creosote buildup.
• Independent flue: Do not connect this unit to a chimney flue serving another appliance.

The SW500 is approved to be installed with an outside air intake (50FAK or 4FAK) — both are required for mobile home and transportable building installation. This type of installation is also required in air-tight houses and houses with negative pressure problems. Outside combustion air may be required if your stove does not draw steadily, smoke roll-out occurs, wood burns poorly, or back-drafts occur whether or not there is combustion present.

The optional outside air kit is purchased separately through a heater dealer. The air intake kit attaches to the air intake tube at the rear of the stove with an aluminum flex pipe and hose clamp.

• Do not install in a sleeping room.
• Maintain the structural integrity of the mobile home floor, wall, and ceiling/roof.
• Install in accordance with 24 CFR Part 3280 (HUD).
• Use a factory-built chimney that complies with UL 103 standards — must be Type HT (2,100°F).
• Use a spark arrester.
• The stove must be permanently attached to the structure of the mobile home. Use the two mounting holes in the bottom of the pedestal with 3/8 inch bolts through the floor.
• The heater must be electrically grounded to the steel chassis with 8 gauge copper wire using a serrated or star washer to penetrate paint or protective coating.
• Outside air kit (50FAK or 4FAK) is mandatory.
• When moving the mobile home, all exterior venting must be removed; reinstall and secure venting after relocation.

• B36T variable-speed blower kit: 120V AC 0.55A 60Hz. Mounts to a blower bracket on the rear of the stove using six sheet metal screws. The blower circulates warm air from the firebox into the living area. Variable-speed knob on the side of the blower housing — clockwise to turn on and set speed. Recommended to turn off when stove is not in operation. Remove and air-blow clean at the beginning of every burn season.
• Power cord routing: Keep the power cord at least 12 inches (30.5 cm) from any stove or chimney connector surface. Any replacement wiring must have equivalent insulation and temperature rating (105°C).

The SW500 is designed to burn well-seasoned natural wood only. Any type of well-seasoned natural cordwood may be used; higher efficiencies and lower emissions generally result from burning air-dried seasoned hardwoods compared to softwoods or freshly cut hardwoods.

• Maximum log length: 11 inches (279 mm). Logs over 6 inches in diameter should be split before loading.
• Firebox volume: 0.59 cubic feet.
• Combustion chamber: 11.25 by 8.5 inches.
• Load placement: Build the fire directly on the firebrick. Do not use a grate or other means of supporting the fuel. Never put wood above the firebrick lining of the firebox.

• Seasoning time: 9 to 15 months under cover with airflow on all sides until moisture content drops below 20 percent by weight.
• Stack practice: Logs should not be stored directly on the ground; allow 24 to 48 inches of air space between rows; protect the top layer from weather but leave sides exposed to airflow.
• Readiness check: Check the piece ends. If cracks radiate in all directions from the center, the wood should be dry enough to burn. If wood sizzles in the fire even though the surface is dry, it needs more seasoning time.
• Sizzling / hissing / vapor: Signs of wet or freshly cut wood. Do not burn wet wood — it produces excessive creosote and impairs combustion.

A single manual slide damper rod located in the center of the stove under the hearth plate controls combustion air. Pulling the rod out increases air; pushing it in reduces air.

Federal regulations prohibit operating the SW500 with anything other than well-seasoned natural cordwood. Do NOT burn: garbage, lawn clippings or yard waste, materials containing rubber (including tires), materials containing plastic, waste petroleum products, paints or paint thinners, asphalt products, materials containing asbestos, construction or demolition debris, railroad ties or pressure-treated wood, manure or animal remains, salt-water driftwood, unseasoned wood, paper products, cardboard, plywood, particleboard, or manufactured wax-impregnated logs. Burning these materials may release toxic fumes, will void the warranty, and creates fire hazards.

• Top-down fire building method recommended. Place the largest split pieces on the bottom laid parallel and close together; smaller pieces crossways in a second layer; still-smaller pieces crossways with spaces in a third layer; kindling and twisted newspaper sheets on top.
• Chimney warm-up: Before igniting, twist newspaper into a torch and hold it close to the mouth of the chimney inside the firebox to initiate updraft and prevent back-drafting.
• Never over-fire. If any part of the stove starts to glow red, the stove is being over-fired. Close the door and shut the damper immediately to reduce air supply and slow the fire.
• Ash management: Remove ashes when 3 to 4 inches deep. Leave approximately 1 inch of ash on the firebox bottom to maintain a hot charcoal bed. Place ashes in a tight-fitting-lid metal container on a non-combustible surface until thoroughly cooled.
• Glass care: The pyroceramic glass and air wash system keep the viewing window clean during normal operation. Never use abrasive cleaners on the glass; only specialized stove glass cleaner sold for this purpose, applied when glass is cold.

Compare the SW500 against the Big E pellet stove or browse the full Breckwell collection.