Pellet Stove Flue Pipe: What You Need to Know

The pellet stove is a rather unique appliance with a specific set of instructions and requirements. There are two types of pipe that play a significant role in their installation. The first is the pellet stove pipe, and it is used to connect the pellet stove to the second pipe, which is the pellet stove flue pipe.

In this article, we’ll take a closer look at these stoves and the prerequisites for their installation.

What is a Pellet Stove?

A pellet stove is a specific type of wood-burning stove. Rather than using firewood, natural gas, or other types of fuel, pellet stoves work on compressed wood pellets.

These stoves are specifically designed as heating devices, not for cooking food or similar uses. If you decide to use this type of device, it's essential that you size it properly. If the pellet stove is too small for the space, it won't offer sufficient heating. On the other hand, a pellet stove that's too large will burn through fuel at an alarming rate and overheat the space.

Do Pellet Stoves NEED a Chimney?

The simple answer to the question is no. Pellet stoves do not require a chimney in order to function. However, they do need to vent any combustion gases that they produce somehow. The best way to do this is via the use of a flue, which is essentially a prefabricated metal chimney pipe.

How to Install a Pellet Stove Chimney Flue

When installing your new pellet stove, you have several options:

1. If your home has a pre-existing class 1 chimney, you can simply connect the flue to the liner on your existing chimney.
2. You can run the flue through the wall and up an exterior wall of your house.
3. You can run the flue up an interior wall of your home and through the roof.

Installing a Pellet Stove Flue Pipe Externally

If you choose to install your flue pipe externally, you’ll need to use a twin-wall flue pipe. The process is fairly simple:

1. Connect your pellet stove pipe to the socket on the back of your stove.
2. Run the stove pipe horizontally to your pellet stove flue pipe.
3. The pellet stove flue pipe needs to run horizontally through the exterior wall, and then up the exterior wall till it reaches a certain height. (More about appropriate chimney height)

Installing a Pellet Stove Flue Pipe Internally

If you choose to run the pellet stove flue pipe internally, there are two options. First, you can connect your pellet stove to an existing chimney. This is as simple as:

1. Connecting the pellet stove pipe to the socket in the rear of the pellet stove.
2. Connecting the pellet stove pipe to the flue pipe.
3. Connecting the flue pipe directly to the existing chimney flue liner.

The other option is to install a brand new flue that runs up the inner wall of the house. This isn’t particularly complicated either and is as simple as:

1. Connecting the pellet stove pipe to the stove.
2. Connecting the stove pipe to the pellet stove flue pipe.
3. Installing and securing the flue pipe to the internal wall.
4. Running the flue pipe up through the roof using an appropriate connection system.

Of course, these are nothing but the most basic instructions. All pipes also need to be fixed appropriately to ensure that they’re safe and don’t move.

Pellet Stove Flue Pipe Sizing

Installing an appropriately sized flue (specifically flue diameter) is very important for safe and efficient operation. Pellet stoves generally use only a small diameter flue pipe of 100 mm.

During installation, it's essential that you seal the joints and seams of the flue with a sealant recommended by the flue manufacturer or supplier.

Planning and Preparation

Before installing a pellet stove or pellet stove flue pipe, there are some things to do and consider. Some of these include the following:

• Read the pellet stove manual: It’s always a good idea to read the manual for your specific stove so that you’re familiar with all the requirements, clearances, and recommendations for your model.
• Review Building Regulations Document J: Building document J is a guide that outlines the legal requirements for solid fuel burning appliances in the UK. It includes flue specifications.
• Choose the right flue pipe: Ensure that you choose a double-wall, insulated system that is compatible with pellet stoves. Different brands and models may lend themselves differently to compatibility with certain systems.
• Plan the flue route: It’s essential to plan the flue’s route to minimize bends and ensure that there are adequate clearances from walls, ceilings, and combustible materials.
• Check for obstructions: Before installing the flue, ensure that the planned route is clear of electrical wires, plumbing, and other structural elements.

Regulations for Pellet Stove Flue Pipe

As mentioned earlier, there are a few regulations that you need to follow when installing pellet stove flue pipes. Some of these include the following:

• Clearance Requirements - When installing a pellet stove, ensure that you meet the minimum requirements for providing clearance between it and other objects, specifically flammable ones.
• Pipe Materials - Ensure that the pellet stove flue pipe you choose is of a material that matches the safety regulations for flue pipes.
• Ventilation - Badly ventilated flues can be a serious safety hazard, so ensure that you meet the safety regulations for ventilation as well.

Final Thoughts

Installing a pellet stove flue pipe is essential and has a few highly specific requirements. In this article, we've discussed some of those requirements and the steps involved in the installation.

If you feel that you'd be best served having someone install your pellet stove pipe for you, have a look at our range of flue pipes, and we'll be happy to help you.