If you want to heat your home or any other internal space such as an office/workshop with pellets one of the simplest methods is to use a pellet stove. If you want a hydronic (wet) heating system with radiators or underfloor heating you will need to use a pellet boiler. However, for most small homes with an open plan layout, a pellet stove is perfect for either dedicated or supplemental heating. With this post, I wanted to discuss the process of how to install a pellet stove. The various considerations you have to think about. Not only for the pellet stove to perform to the best of its ability but also important safety considerations.
Generally, the process of how to install a pellet stove is very similar across all brands/makes and models. However, always check the specific manufacturers instructions: Image – Amazon
With this post on how to install a pellet stove its not specifically focused on any particular brand/make or model of pellet stove. Its simply a general discussion on the principle of how to install a pellet stove. Once you have chosen the specific wood pellet stove you want to install, follow the manufacturer’s installation instructions. I’ve referenced two videos below. One is of a professional installation and the other is a DIY installation. They generally cover the same process. However, they show two slightly different scenarios. For instance, one shows the installation of the flue pipe through a wall with metal siding, the other with vinyl siding.
Introduction On How To Install A Pellet Stove
As references above, I’ve included two of the best videos I’ve found covering how to install a pellet stove. One is of a professional installation and one is a DIY video. I would encourage you to watch both of them. While they are both installing a similarly sized pellet stove in a corner installation there are a few differences between the two installs. I’ll be referencing both of these videos in the rest of my post below.
Where To Position The Pellet Stove?
For the sake of this post, let’s presume you have already chosen your pellet stove and it will produce a sufficient heat output for your home. When I get around it to I will write a post on the subject of how to choose a pellet stove, as your decision will need to be based on various factors. Such as how large your home is, what type of climate your home is located in and what grade of wood pellets you want to burn. However, to continue this discussion on how to install a pellet stove, let’s presume you have picked your stove already. In terms of where you should/can position the pellet stove you need to consider these questions/factors.
- A location that will provide good heat distribution.
- Out of the way of foot traffic for safety.
- Ideally not located under/next to a window (at least 18″ away).
- Close to a 110V wall outlet for power.
- A safe distance from combustible surfaces.
Clearances To Combustibles
One of the most important aspects to consider when choosing the location for a pellet stove or any stove for that matter is clearances to combustibles. Stoves obviously get very hot, and you need sufficient clearance from combustible materials for a safe installation. Now, as you may have noticed from the professional installation video above, pellet stoves do differ from a typical log stove. For instance, clearance to combustibles with a log stove is 18 inches around the stove. However, with a pellet stove the requirement is only 3 inches.
As well as freestanding stoves you can also get fireplace insert pellet stoves: Image – Amazon
Why does a pellet stove require a reduced clearance to combustibles? Well, a pellet stove is a controlled burn, only a small number of pellets are burning at any one time. Hence, a pellet stove will not produce some of the extremely high surface temperatures log stoves can produce. The advantage being you can do a corner install with a pellet stove which is by far one of the most common installation choices. However, with any stove, you have to make sure its not sitting on a combustible surface either. If you have a tiled/stone floor that’s fine. However, if you have a wood or vinyl/laminate floor you must position the pellet stove on a stove board.
In many cases, a stove board such as this made of non-combustible fibreboard is required for a safe pellet stove installation: Image – Amazon
Wood Pellet Stove Flue Pipe Installation
Both of the two videos above do a good job at showing the process of how to safely drill through the wall for the flue pipe while importantly avoiding a stud. If your home has metal siding as shown in the professional installation video the installer does a nice of cutting grooves into the siding so the exterior plate sits flush. The DIY installation video shows how to install the exterior plate into a wall with vinyl siding by fitting metal angle. What I wanted to discuss in a bit more detail is proper sealing of the flue pipe and air sealing around the vent to reduce draughts into your home due to the install. After all the point of the pellet stove is to help heat your home. You don’t want a poor install to let cold air in.
Pellet Stove Flue Pipe Sizes and Installation Tips
As you can see in the professional pellet stove installation video above pellet stove vent pipe resembles gas stove flue pipe more than a wood stoves chimney. Pellet stove vent pipe has a 3″ stainless steel interior pipe with an air gap and then a 4″ outer pipe of galvanised steel. Two very important components of the pellet stove flue pipe installation are the interior wall thimble and the exterior wall thimble. As you can see in the video, the interior and exterior wall thimbles fit inside one another. This provides additional heat/fire protection for any combustible materials in the wall.
A typical example of a pellet stove vent pipe kit with interior and exterior wall thimble plates: Image – Amazon
As shown in the videos above, pellet stoves, unlike most log stoves, use a source of external input air for the combustion process. The advantages of this are it does not create draughts through your home while the stove is running which a log stove can. Furthermore, with many homes today built to higher airtightness standards, there simply may not be enough incoming air to run the stove without external direct supply. However, this means you do have to be careful with the positioning of the flue and the air inlet. You don’t want them to be too close together so the fresh air inlet on the pellet stove is sucking in flue gases. This will reduce the combustion efficiency and heat output of the pellet stove.
If you want your pellet stove to burn wood pellets as efficiently as possible it must receive a sufficient supply of clean fresh air: Image – Amazon
A good tip shown in the DIY video above is to use mineral wall insulation in the wall around the wall thimble inserts. Its also commonly referred to as Rockwool. This is a none combustible insulation product. Another important part of the installation is to properly join and seal the pellet stove vent pipe. While the pellet stove pipe sections do push together well to create a tight seal to do the best job possible you need to use a fire-rated caulking product. These are available from brands such as 3M and NSI. It just provides further reassurance that each pipe joint is gas tight to stop flue gases escaping into the home.
Using a fire-rated vent pipe sealant within each of the joints will ensure a gas-tight seal: Image – Amazon
Never Use Standard Spray Foam To Seal Around The Vent Pipe Thimble Plates!
Now, when various other holes are drilled through a building fabric (walls) for services such as electrical cables and drain pipes a tin of builders spray foam will be used to seal up the gap. It not only provides an airtight seal but the foam its self has insulating properties. However, you should never use standard builders spray foam for sealing around a thimble plate, its not fire retardant. In fact, not only is standard spray foam not fire retardant, in many cases its extremely flammable.
You need to be very careful using spray foam products to seal around wall thimble plates, you should only use fire rated products: Image – Amazon
Conclusions on How To Install A Wood Pellet Stove
While the two videos above can give you a good general understanding of the proper installation process for a pellet stove you must always check the manufacturer’s instructions as well. Furthermore, the requirements for distances to combustible surfaces/building code can change over time. Therefore, make sure you know what the latest building codes are for your area before you start the installation.
I have lots of other relevant posts you may want to look into. For instance, I have posts discussing how important it is to keep pellets dry to stop them from going bad. Furthermore, I also have posts on pellet storage/vacuum systems and when/how to accept bulk blown deliveries of pellets. For all pellet stove owners, these are important topics of discussion. Thanks for reading. 🙂