ComfortBilt HP22i Pellet Stove Insert

The ComfortBilt HP22i pellet stove insert turns an existing masonry or factory-built fireplace into a thermostat-controlled heater. It heats up to 2,800 sq ft and delivers 9,696 to 40,689 BTU/h in EPA testing. The 47 lb hopper runs up to 18 hours on the lowest of five heat settings. It is EPA 2020 certified at 1.01 g/h with 80.5% weighted average efficiency (HHV). A room blower, automatic ignition, a programmable thermostat, a remote and a 43" x 32" surround panel are included. It exhausts through a 3" port with a 2" fresh-air intake and needs a pellet liner up the chimney. Choose Black or Black with stainless trim.

Who the HP22i is for

The HP22i makes sense when you have a fireplace that sends more heat up the chimney than into the room:

• Homes up to about 2,800 sq ft, heated from the main living area.
• Fireplaces at least 21" wide, 24 1/2" high and 18" deep inside, ComfortBilt's minimum cavity size. Measure before you order.
• Built-in installs in a framed enclosure, where outside air is mandatory.

Don't install it in a bedroom; the manual prohibits sleeping rooms. It also needs electricity: in a power outage it shuts down safely and does not restart on its own.

Hopper and burn time

The 47 lb hopper holds a little more than one 40 lb bag. ComfortBilt rates it at up to 18 hours on the lowest setting; higher settings burn through it faster. The built-in heat tube scraper, a glass airwash damper and a removable ash pan keep weekly cleaning quick.

Heat output and efficiency

EPA testing puts the HP22i at 9,696 to 40,689 BTU/h, with 80.5% weighted average efficiency (HHV) and 1.01 g/h particulate emissions. That's the same rating as the freestanding HP22. With ECO enabled, the insert cycles off and relights on its own in Temp and Weekly modes to hold your set temperature on mild days.

Controls

The control panel sits in the surround and offers four modes: Manual (five heat levels), Temp, Weekly (a program for each day with up to four time blocks) and Thstat for a wired wall thermostat. The room temperature sensor routes out through a conduit in the shroud, and the included remote handles day-to-day changes.

HP22i vs. HP22 vs. Escape 1800-I

If you're not tied to the fireplace, or you'd rather burn wood, compare these two:

↔ Swipe the table to see more →

The HP22 is the same heater in a freestanding cabinet; pick it if you'd rather vent through a wall than up a chimney. The Escape 1800-I is the choice for cheap or free firewood and heat during outages, at the cost of loading logs every few hours.

Venting and the liner kit

Use only 3" or 4" Type L or PL pellet vent. ComfortBilt recommends a flexible liner: with rigid pipe, the insert can't be pulled out for its annual cleaning. Our HP22i liner kit (L315PK-CB) is the 3" flexible liner with the clean-out tee that connects to the back of the insert. The manual calls for 4" vent if the flue is taller than 12 ft or the home is above 5,000 ft, so call us before ordering for a tall chimney. Maximum equivalent vent length is 17 for 3" vent and 27 for 4". Vertical liner counts ½ per foot and each tee or 90° elbow counts 5.

Before installation, remove the fireplace damper or fix it open. Seal the throat with a sheet-metal block-off plate around the liner. Never connect the insert to a flue that serves another appliance. See our pellet stove venting guide for more on pellet venting.

Clearances and floor protection

The hearth under the insert must be non-combustible and extend at least 6" in front of the door and to both sides. Many masonry hearths already do; if yours falls short, add a pad from our hearth pads. Wood mantels and trim need room: 8" from the top of the heater to a mantel, 6" to top and side facings, and 8" to a side wall. See the clearance table below.

Why buy the ComfortBilt HP22i from StoveSource

• No Sales Tax in any state.
• Free shipping to the lower 48. Ships in 1–3 days.
• Authorized ComfortBilt dealer, with the full manufacturer's warranty.
• Price match guarantee.
• Real help measuring your fireplace and sizing the liner: email info@stovesource.com or text 1-888-866-8206.