Kozy Heat Chaska 25 Gas Insert
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
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®
Transform your existing wood-burning fireplace into a clean, convenient, and efficient source of warmth with a Kozy Heat gas fireplace insert. Designed to fit inside many masonry or factory-built wood fireplaces, Kozy Heat gas inserts deliver realistic flame presentation, dependable heat, and the everyday convenience of natural gas or propane.
A gas insert uses a sealed firebox and venting system to draw combustion air from outdoors and exhaust fumes safely outside through the existing chimney chase.
Distinctive Features
Convert an Existing Fireplace Without Starting Over
Enjoy the charm of your existing fireplace with the push-button convenience of gas. Kozy Heat gas inserts are a great solution for replacing messy wood fires with steady, controllable comfort.
Direct Vent Performance
Get warmth where you want it most. Kozy Heat direct vent gas inserts are built to deliver dependable heat while using your existing chimney as the venting path.
Traditional or Contemporary Fireplace Looks
Whether your home leans rustic, transitional, or modern, Kozy Heat gas inserts give you design flexibility with realistic flame options, decorative fronts, and finish choices that complete the room.
Kozy Heat Gas Insert FAQs
What is a Kozy Heat gas fireplace insert?
A gas fireplace insert is a gas-burning appliance installed inside an existing wood-burning fireplace. It updates the old fireplace with a sealed gas firebox, burner system, and venting.
Can a Kozy Heat gas insert go into my existing fireplace?
In many cases, yes. Gas inserts are designed for existing masonry or approved factory-built wood fireplaces, but exact fit depends on the fireplace opening, chimney condition, venting requirements, and the specific Kozy Heat model.
Do Kozy Heat gas inserts use natural gas or propane?
Many Kozy Heat gas inserts are available for natural gas or propane. Fuel availability depends on the model and installation setup.
Do I still need my chimney?
Yes, but not in the same way as a wood fire. A direct vent gas insert commonly uses the existing chimney as a chase for the intake and exhaust venting system.
Are gas inserts good for zone heating?
Yes. A Kozy Heat gas insert can help heat the room or area where you spend the most time, reducing reliance on whole-home heating in some situations.
Do Kozy Heat gas inserts require professional installation?
Yes. Gas inserts should be measured, selected, vented, connected, and tested by a qualified fireplace professional. At all Leisure Time Inc. locations we offer the services necessary to get your fireplace insert properly installed.
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