Fireplaces and flues
Pellet stoves, what a yearly service covers and why the vent matters
We clean pellet stoves and pellet inserts across the Portland metro, from the burn pot to the vent termination. What usually stops one is fly ash packed in the heat exchanger, blowers and vent, which starves the fire and trips the vacuum switch.
Updated
What a pellet stove is and how it vents
A pellet stove is an electric-fed wood heater. A hopper holds the pellets, an auger drops them into a burn pot, one blower pulls air through the fire and pushes the exhaust out the vent, and another moves room air across a heat exchanger.
Because a fan drives the exhaust, the vent is a small sealed pipe rather than a chimney: out through the wall and up a short rise, straight up through the roof, or down an old masonry chimney as a liner. Fly ash settles in every horizontal run and elbow, so the vent is cleaned with the stove.
In Oregon the pellet stove sits in its own legal box, exempt from the stove rules that catch wood stoves at a home sale and treated differently by the county burn bans. It also needs power, which matters in the metro's ice storms and east wind outages.
How to tell what you have
A pellet stove is easy to pick out once you know the parts.
- A lidded hopper on top or at the back holding a bag or two of pellets, with an auger you can hear turning.
- A small cast or steel burn pot behind the glass, with a fire that sits in the pot instead of filling the firebox.
- A power cord to a wall outlet and a control board with a dial or a digital panel; the stove will not run without them.
- A thin vent pipe a few inches across leaving the back or top, often straight out through the wall to a hooded termination.
What you will find in Portland homes
The pellet units we service around the metro break down like this.
| Type or model | Era | Notes |
|---|---|---|
| Freestanding top-feed stove | current | The auger drops pellets from above into the burn pot; ash and clinker build there and must be scraped, and a pot left full is the usual reason a stove will not light. |
| Freestanding bottom-feed stove | current | Pellets push up into the pot from below and ash spills over the sides into a pan; more tolerant of low-grade pellets, though the exchanger passages still pack with ash. |
| Pellet insert in a masonry fireplace | current | The stove body sits inside the old firebox behind a surround, the hopper under the glass; the vent is a liner up the chimney, and the unit comes forward for the full cleaning behind it. |
| Through-the-wall vent with a short rise | Any | The simplest run and the one that smokes the room in a power failure; a few feet of vertical pipe outside gives some natural draft, and we check the termination's distance from windows, decks and the ground against the manual. |
What goes wrong and what fixes it
Each pellet stove fault below is paired with the service that clears it.
-
Ash packed in the heat exchanger, ash traps and exhaust passages, with a lazy orange flame and sooted glass
Full teardown: pot scraped, traps emptied, exchanger brushed, blowers pulled and cleaned, vent swept to the termination, then a start-up test Pellet Stove Cleaning, from $299
-
A stove that shuts down mid-burn, will not light or trips its vacuum switch
The exhaust path cleared first, since a blocked vent is the usual cause, then the switch, igniter and blower tested Pellet Stove Cleaning, from $299
-
Smoke smell in the room, soot on the wall behind the stove or around the termination
A Level 2 look at the vent joints, wall thimble and termination, with the leaking joint identified Chimney Inspection, from $129
-
Pellet vent run into a masonry chimney with no liner, ash coating the flue
A liner dropped the length of the flue and connected to the stove vent, the old flue sealed around it Chimney Liner Installation, from $1999
-
Termination hood plugged with ash or a nest, or missing its screen
The maker's termination cap for that vent size, with a screen that can be cleaned Chimney Cap Installation, from $299
What a yearly pellet stove service covers, in order
A yearly pellet service covers the burn pot, the heat exchanger and blowers, the vent to its termination, and the gaskets, then ends with a test burn.
Firebox and burn pot
Pot out and scraped to bare metal, igniter checked, ash traps and pan emptied, the firebox vacuumed with a filtered vacuum that keeps fine ash out of the room.
Heat exchanger, blowers and switches
The exchanger tubes scraped, the hidden passages behind the baffles vacuumed, both blowers pulled and their blades cleaned of the ash cake that unbalances them, and the vacuum and high-limit switches checked with their hoses.
Vent to the termination
The pellet vent brushed from the stove to the outside hood, elbows and the tee cap emptied, the termination screen cleaned, the joints and wall thimble looked over for separation and soot.
Gaskets and the start-up
Door, glass and ash-pan gaskets checked, the hopper lid seal too, then the stove lit and run up to temperature so you see it feed, ignite and vent before we leave.
How often a pellet stove needs cleaning in a Portland winter
Follow the manual's schedule: the burn pot and ash pan daily or weekly by you, the full teardown with the vent once a year by us, sooner when the stove is the main heat or burns low-grade pellets.
Put the stove on a battery backup if your street loses power in ice storms, because a stove that dies with a full pot and a hot vent can push smoke into the room. If smoke ever comes from the stove or the vent joints, shut it off and call before the next fire.
Pellet stoves and Oregon's rules: exempt from the stove law, not from every burn ban
A pellet stove is exempt from Oregon's home-sale removal law, so it stays with the house at a sale, label or not.
Burn bans are a different matter. Washington County's ordinance leaves pellet stoves alone on red days, while Multnomah County's covers them, with exemptions such as a pellet stove that is the home's only heat.
A pellet stove still makes carbon monoxide, and a vent separated at a joint or a termination iced over puts it into the room. Keep an alarm on the same floor and treat a soot smudge on the wall behind the stove as a vent problem, not a cosmetic one.
Pellet stove questions
Does a pellet stove have to be removed when I sell my house in Oregon?
No. Pellet stoves are exempt from Oregon's home-sale removal law, which is aimed at uncertified wood stoves and wood-burning inserts. Yours stays with the house whatever its age. What a buyer's inspector cares about is the vent: a clean exhaust path, tight joints and a termination that matches the manual.
Why does my pellet stove smell like smoke in the room?
A leak in the exhaust path, since a pellet stove runs under slight negative pressure and should put no smoke in the room at all. The usual spots are a vent joint that has pulled apart, a flattened door or ash-pan gasket, or a termination blocked enough that exhaust backs up. Shut it down and have the vent inspected first.
How often does a pellet stove really need a professional cleaning?
Once a year at minimum, on top of the weekly pot and pan cleaning you do yourself. Sooner when it is the main heat or burns through pellets by the ton. The service is about the parts you cannot reach: the exchanger passages, the blowers and the vent.
Can a pellet stove vent into my old brick chimney?
Yes, through a liner dropped the length of the flue and connected to the stove vent, with the old flue sealed around it. A pellet vent that just ends inside an open masonry chimney coats the brick with fly ash, loses its draft on cold days and backs up in an outage; we camera the flue and fit the liner.
What happens to a pellet stove when the power goes out?
The auger and blowers stop and the fire in the pot smolders out. On a stove vented straight out the wall, the lingering smoke can drift into the room instead of up the pipe. A small inverter or battery backup keeps the exhaust blower turning until the fire dies.
Related pages
Pellet stove calls near you
Pellet stove work has taken us to Piedmont and Humboldt, Southwest Hills and Council Crest, Woodstock and the rest of the metro, and the posted price is the same at every address.
Other fireplace and flue types
Ready to book a sweep?
Call with what the fireplace is doing, or text a photo of the opening and one of the chimney top, and we will name the service and its posted price before we come out.