Pellet Stove Venting: How It Works and What You Need

Updated October 2026

Pellet stoves don't use a chimney the way wood stoves do. The exhaust blower pushes combustion gases out through small-diameter pellet vent pipe (Type L/PL) — which is why a pellet stove can vent through a wall where a wood stove never could.

Here is what the pipe is, what a typical install needs, and what every part costs. To shop by size, see all pellet stove vent pipe and fittings.

What pellet vent pipe is

Pellet vent is double-wall pipe with a stainless inner liner, listed specifically for pellet exhaust temperatures and the slight positive pressure a pellet stove's blower creates. Sections twist-lock together with a gasketed seal.

Single-wall stovepipe and dryer duct are never acceptable substitutes. Pellet exhaust is under pressure, so a leaking joint puts combustion gases into the room rather than drawing air in the way a wood stove's negative-pressure flue does. This is the one place in a pellet install where there is no cheaper alternative worth considering.

Size: pellet vent is sized by the stove's flue collar, not by brand. The PelletVent Pro and Vortex pipe we stock fits any pellet stove with a 3" or 4" flue collar, whoever made the stove. Most stoves have a 3" collar. Go to 4" when your manual calls for it, usually on a long run (a high equivalent vent length once elbows are counted) or at high elevation. The venting table in your stove's manual gives the exact cut-off. To step up from a 3" collar, start with the 3" to 4" increaser. The Drolet ECO-65R, the largest pellet stove we stock, vents on 4" from the start, so it takes the Vortex 4" parts rather than a 3" kit with an increaser.

Pellet stove exhaust pipe: the same thing by another name

If you are searching for pellet stove exhaust pipe, this is the pipe you need. "Exhaust pipe," "vent pipe," "pellet vent" and "PL vent" all describe the same listed double-wall pipe running from the stove's exhaust outlet to the outside. There is no separate exhaust part — the run starts at the appliance adapter on the stove's exhaust collar and ends at the termination cap, and every part in between is in the price list below.

Two things to check before you buy: the diameter of your stove's exhaust collar (3" or 4", stated in the manual), and the manual's maximum vent length and elbow count. Those two numbers decide which kit fits.

Can you vent a pellet stove out a wall?

Yes — through-the-wall is the most common pellet install and the cheapest. The pipe leaves the back of the stove, passes through a wall thimble that keeps the required clearance to the wall framing, and ends at a horizontal termination cap outside. The cap has to sit the manual's minimum distance from windows, doors, soffits, decks and grade, so check those numbers before you cut the hole. Our pellet stove installation guide walks through the full through-wall install step by step.

Buying the stove and the vent together

If you are speccing venting because you are about to buy a stove, these are the two pairings to start from:

• Drolet ECO-65R ($4,129, Ships in 1–3 days) with the Vortex 4" ground floor kit ($699). The ECO-65R heats 800–2,600 sq ft, runs up to 105 hours on its 125 lb hopper, and burns at 0.77 g/h — the cleanest stove we carry.
• ComfortBilt HP22 ($2,399) with the ComfortBilt 3" DuraVent kit ($429) — the budget pairing, and the one most people buy.

For the Drolet ECO-55 (No confirmed date) and Englander 25-CBPAH (No confirmed date), check the live shipping status before you order venting; their factory venting bundles follow the same status. Need it sooner? The closest match is the Drolet ECO-65R, $4,129, 800–2,600 sq ft (Ships in 1–3 days).

Pellet vent pipe and fittings: full price list

We stock DuraVent PelletVent Pro and Vortex. Individual parts:

Part	Use	Price
3" appliance adapter	Stove collar to vent — every install	$36.95
3" straight pipe	The run itself	$39.41
3" horizontal termination cap	Through-wall exit	$63.99
3" 45° elbow	Gentle direction change	$83.48
3" wall thimble	Safe wall pass-through	$84.99
3" 90° elbow	Right-angle turn	$99.86
3" to 4" increaser	Long runs needing 4"	$119.99
3" chimney adapter	Into an existing chimney	$127.99
3" tee with clean-out cap	Vertical rise plus service access	$135.87
3" increaser adapter tee	Combined tee and step-up	$189.99
3" wall thimble + outside air kit	Mobile home required; recommended for tight houses	$269.99

Or buy the kit

Specifying part by part is fine if your run is unusual. For a standard install, the kits are cheaper and nothing arrives missing:

Kit	For	Price
ComfortBilt 3" pellet vent kit (DuraVent)	All ComfortBilt freestanding stoves, through-wall	$429
ComfortBilt HP22i liner kit	Required flexible vent for the HP22i insert	$489
Vortex 3" ground floor kit	Ground-floor through-wall	$629
Vortex 4" ground floor kit	Ground-floor, 4" systems — including the Drolet ECO-65R	$699

The two configurations

Through-the-wall (horizontal). Pipe exits behind the stove, through a wall thimble, to an outside termination cap. The most common install and the cheapest. Most manufacturers recommend a short vertical rise before the horizontal run so the stove drafts naturally if the power fails mid-burn — that is what the clean-out tee is doing, and it doubles as your service access.

Vertical (up and out). Pipe rises inside and exits through the roof, or runs up an existing chimney using the chimney adapter. More parts and more cost, better natural draft.

Through an insulated attic. If a vertical run passes through an insulated attic, the Vortex installation instructions require an attic insulation shield there to keep the insulation off the pipe: the Vortex 3" attic insulation shield (VOP0300) or the Vortex 4" attic insulation shield (VOP0301). They fit Vortex pipe only.

Fresh air intake. Most pellet stoves have a dedicated outside-air connection. It is required for mobile home installs and a good idea in tight modern houses — the stove stops competing with your bathroom fans for air. Our fresh air intake guide covers when it matters, and the pellet outside air kit table below shows which kit fits.

Outside air kits for pellet stoves (any brand with a 2" intake)

Most pellet stoves have a small outside air collar on the back, usually 2". An outside air kit connects that collar to the outdoors, so the stove burns outside air instead of warm room air. Unlike wood stove kits, pellet outside air kits are not brand-specific. If your stove has a 2" intake, any of the 2" kits below fits it. Check the intake size in your manual before you order.

There are two ways to do it. A 2" kit goes through its own small hole in the wall. A wall thimble kit brings the vent out and the air in through the same hole, but it must match your vent size and pipe system (PelletVent Pro only joins PelletVent Pro, Vortex only joins Vortex).

↔ Swipe the table to see more →

Mobile and manufactured homes: outside combustion air is required. A pellet stove in a mobile home must draw its air from outside, and the stove itself must be listed for mobile home installation. Check the manual for both before you buy.

Other homes: outside air is optional but worth it in a tight, newer house or a basement, where bathroom fans and a range hood compete with the stove for air and can cause smoky starts and shutdowns. Every kit ships with No Sales Tax in any state, and free shipping on orders over $300. See all fresh air intake kits.

Venting a pellet insert

Inserts like the ComfortBilt HP22i vent up the existing fireplace chimney through a 3" flexible liner connected with a tee at the appliance — not rigid pipe, because the insert has to come out for chimney cleaning. The HP22i liner kit ($489) bundles the liner, tee and termination for a standard masonry chimney.

Note this is different from a wood insert liner, which is 6". Our chimney liner guide covers that side.

Keeping it clean

Pellet vent needs annual cleaning — more often if you burn lower-grade pellets. Ash accumulates in the horizontal run and at the tee, and a restricted vent shows up as poor combustion and shutdown faults long before you would think to look at the pipe.

• 3" pellet vent cleaning kit — $145, for the full vent run
• ComfortBilt B67C brush kit — $30.99, fits all ComfortBilt stoves

The rules that actually govern your install

Termination clearances — distance from windows, doors, air intakes, grade and combustibles — are set by your stove's installation manual, the vent manufacturer's listing, and local code (NFPA 211 in most of the US). The manual always wins over any general guide, including this one. Every stove we sell links its installation manual on the product page; read the venting section before ordering parts.

Common mistakes

• Too many elbows. Each 90° adds resistance. Exceed the manual's equivalent-length limit and the stove soots up and shuts down. Two 45° elbows are gentler than one 90° where the geometry allows.
• No cleanout tee. You will regret it at the first ash-season cleaning.
• Terminating under a deck, soffit vent, or a window that opens. Check the clearance diagram before you cut the hole.
• Skipping the outside air kit in a tight house. Erratic burn behaviour traces back to this constantly.
• Using the wrong pipe. Worth repeating: pellet exhaust is pressurised. Only listed pellet vent.

Cleaning the vent: brush 3" and 4" pellet vent pipe at least once a season with a pellet vent cleaning brush. See all chimney brushes and cleaning tools.

Related guides

• Pellet stove in a basement: venting and outside air
• Pellet stove for a garage or shop
• How to Install a Pellet Stove: Steps and Cost
• Pellet Stove Inserts Guide
• Hearth Pads: What You Actually Need
• Pellet Stove Troubleshooting
• The Most Efficient Pellet Stoves
• Best ComfortBilt Pellet Stoves

Ready to spec it? Shop pellet stove vent pipe and fittings at StoveSource — authorized dealer, No Sales Tax in any state, free shipping on qualifying orders — or order the 4" ground floor kit with an ECO-65R, or the 3" freestanding kit or insert kit with a ComfortBilt. Email info@stovesource.com or text 1-888-866-8206 and we will build the parts list for your exact layout.