The Kozy Heat Chaska 25 is the smallest gas fireplace insert in the entire Kozy Heat lineup — engineered specifically for the most compact existing masonry fireplaces where even other compact inserts won't fit. With a fireplace opening requirement of just 25-7/8 inches wide (smaller than any other Kozy Heat insert), 26,000 BTU/hr of clean direct-vent heating, 77.58% efficiency on natural gas, included battery backup for power-outage starting, and lifetime quick-latch ceramic glass, the Chaska 25 fits installations no other Kozy Heat insert can accommodate while still delivering meaningful heat output and the longest-lasting glass technology in the line. The Absolute Smallest Gas Insert in the Kozy Heat Lineup The Chaska 25 fits cavities even the Chaska 29 can't accommodate. Many of the smallest pre-1900 home fireplaces, small bedroom or library fireplaces, and certain mobile home installations have openings under 29 inches wide — too small even for the Chaska 29 (the next-smallest option). The Chaska 25 requires just 25-7/8 inches of opening width and 15-1/4 inches of depth, making it the only Kozy Heat insert that fits these ultra-compact installations. If you've measured your fireplace and found it's just barely too small for the Chaska 29, the Chaska 25 was specifically engineered for this exact scenario. The Chaska 25 isn't just a smaller version of the Chaska 29 — it has its own purpose-built feature set, including some genuinely impressive technology for an insert at this size class: 26,000 BTU/hr input (Natural Gas) or 25,500 BTU/hr (LP) — substantial heat output for a compact insert, well-matched to smaller rooms Higher efficiency than the larger Chaska 29 — 77.58% NG / 78.17% LP (Steady State). The Chaska 25 is actually the second-most-efficient insert in the Kozy Heat lineup behind only the premium Chaska 335S. Battery backup included — the SIT ProFlame 2 electronic ignition system can start without household electricity using battery power. Unique to the Chaska 25 in the lineup. Lifetime quick-latch ceramic glass — Kozy Heat backs the glass on the Chaska 25 with a lifetime warranty. The quick-latch design also makes annual maintenance significantly easier. Standard 75 CFM blower (fan kit) — fan kit included, not an upgrade Refractory brick lining standard — traditional brick interior included with upper hood and lower grill Log set included — no need to purchase separately Full-function remote control included — adjusts flame size, fan speed, and on/off operation Co-linear direct vent (3" combustion air / 3" exhaust) — sealed combustion system runs through the existing chimney Bedroom AND mobile home approved — same approvals as the Chaska 29 Canada P-4 approved — efficiency rating recognized internationally Custom Kozy shrouds available — integrate the insert with your existing fireplace surround Will the Chaska 25 Fit Your Fireplace? The Chaska 25's compact form factor opens installation possibilities other inserts can't match, but the existing fireplace still needs to meet minimum dimensions. Minimum specifications: Existing Fireplace Requirement Minimum Front opening width At least 25-7/8" (smallest minimum in the entire Kozy Heat lineup) Back wall width At least 20-5/8" Opening height At least 17-5/8" Cavity depth At least 15-1/4" Chimney condition Solid-fuel masonry or factory-built non-combustible chimney in good structural condition; must be able to accept a 3" co-linear vent through the existing flue Hearth/floor protection Non-combustible hearth in front of the fireplace per local code requirements Gas line access Existing gas line or ability to route a new gas line to the insert location Specifications Brand Kozy Heat Model Chaska 25 Product Type Direct Vent Gas Fireplace Insert (Ultra-Compact) BTU Input (Natural Gas) 26,000 BTU/hr BTU Input (Liquid Propane) 25,500 BTU/hr Steady State Efficiency (NG) 77.58% Steady State Efficiency (LP) 78.17% P.4 Efficiency (ENERGUIDE) ~79% (Canada P-4 approved) Burner Type Fixed output Ignition System SIT ProFlame 2 Electronic Ignition with battery backup Battery Backup Included (unique feature in the insert lineup) Vent Type Direct Vent (3" Co-linear through existing chimney; 3" combustion air / 3" exhaust) Vent Termination Approved for use with ICC Excel DV caps Fuel Type Natural Gas or Liquid Propane (specify at order; LP pilot and burner orifices included) Viewing Area 21-7/8 in. (W) × 12 in. (H) — approximately 263 sq. in. Glass Quick-Latch Lifetime Ceramic Glass Glass Warranty Lifetime (unique among Kozy Heat inserts) Log Set Included Remote Control Full-function (flame size, fan speed, on/off) included Blower 75 CFM fan kit included standard (requires 110V) Refractory Refractory brick lining standard (upper hood and lower grill) Bedroom Approved Yes (direct vent design) Mobile Home Approved Yes Min Fireplace Front Width 25-7/8 in. Min Fireplace Back Width 20-5/8 in. Min Fireplace Height 17-5/8 in. Min Fireplace Depth 15-1/4 in. Estimated Heating Area Up to ~800 sq. ft. (varies by insulation, ceiling height, climate) Warranty Kozy Heat Limited Lifetime Warranty Made In USA (Hussong Manufacturing, Minnesota) Available Options & Accessories The Chaska 25 comes with most features as standard equipment. Decisions during ordering focus on: Fuel Type — Natural Gas or Liquid Propane (specified at order; LP pilot and burner orifices included) Screen Front Options — multiple decorative screen styles available Custom Kozy Shrouds — decorative metal frame that integrates the insert with your existing fireplace surround Decorative Fronts — exterior trim around the firebox opening. Browse our Fireplace Fronts collection for additional compatible styles. Vent Kit Components — sized for your specific installation; approved with ICC Excel DV caps Wall Thermostat — optional upgrade from remote-only control For configuration assistance — choosing the right screen front and shroud combination — contact us. We do this every day. Brand Kozy Heat®
