Fireplaces, Heating Stoves, Flues and Chimneys - Flue for pellet stove on internal wall

Hi,

I have received conflicting information on the type of flue that is required to vent out a wood pellet stove on an internal wall. One salesperson reckoned that I would need to a triple walled insulated flue due to the fact that it is on an internal wall but the stove manufacturer's documentation states that only a 80-100mm (~3-4") flue is required. I do realize that certain clearances will be required from combustable materials in the walls though if the pellet stoves are so efficient (94%), doesn't a triple walled insulated flue seem like total overkill and not to mention expensive.

Appreciate any help on this.

Fergus

Check with local building codes for requirements and restrictions. These tend to vary from area to area. Pellet stoves have much lower emissions than wood stoves, but heat outuput is comparable to cord wood and the same precautions should be taken. This has nothing to do with their efficiency. There is special vent piping for pellet stoves where 3" minimum clearance will be used when going through ceilings and walls where there is anything combustible. These are approved by the Underwriters Laboratories for safety reasons.

As previously stated, local code has final say.

The diameter of the flue pipe has nothing to do with if it's single, double or triple walled pipe. Three to four inch diameter is the size required to let the amount of exhaust out that the stove will produce.

I'm not familier enough with pellets stoves to say if triple wall pipe is required, however, I will say this. Don't let expense overshadow safety. Just because triple jacket pipe is expensive, it's cheaper than the cost of a fire. I've seen too many times where corners were cut or ignorance was applied to venting. From wrong types of pipe to the wrong types of vent caps. The damages cost more than doing right the first time.

Hi,

I have received conflicting information on the type of flue that is required to vent out a wood pellet Stove on an internal wall. One salesperson reckoned that I would need to a triple walled insulated flue due to the fact that it is on an internal wall but the stove manufacturer's documentation states that only a 80-100mm (~3-4") flue is required. I do realize that certain clearances will be required from combustable materials in the walls though if the pellet stoves are so efficient (94%), doesn't a triple walled insulated flue seem like total overkill and not to mention expensive.

Appreciate any help on this.

Fergus

Proper venting is vital to for the performance of your wood pellet stove, safety, keeping maintenance to a minimum, and the quality of the indoor environment. Pellet stoves produce hardly any visible smoke after startup, but exhaust gases, fine ash, and water vapor have to be removed safely from the appliance to the outdoors without leaking into the house. The purpose of all vents is removing combustion byproducts during normal operation. Find out if this likely to be limited by factors such as obstructions above vertical venting through the ceiling and roof or by the distance to an outside wall for horizontal venting.


A few stoves operate without a combustion air fan and use natural draft both for exhaust and combustion air intake. Some heat also moves through the vent. Protection of nearby combustibles is essential. The minimum clearance between the vent and combustibles, as specified in the vent installation instructions, must be met or exceeded to assure safety.

Pellet fireplace inserts and freestanding stoves are often vented into existing masonry and factory-built fireplace and wood pellet stove chimneys