Flue Pipe: What is it and What Are Its Uses?

A flue pipe is an integral component of home heating installations. It is usually located at the fireplace, furnace or water heater installations. Exhaust gases and other byproducts of combustion are expelled into the outside atmosphere through the flue. In this way, pollution of indoor air is prevented. The pipe enables healthy ventilation even as household heating operations take place.

It also acts as a safeguard against accidental fires. Flues are made of metal because it is fire resistant. Usually, the pipe is surrounded by some material to assist insulation. Flues may be categorized into 3 types - fireplace, furnace or water heater flues. Below is a brief description of each and functions.

Fireplace Flue Pipe

The flue is located within the chimney. Most flues are straight as this enables the best draft. Heat resistant materials such as brick, tile and ceramic are used to insulate chimney flues. This is because flue gases transmitted can be very hot. Insulation also makes the fireplace more energy efficient. The chimney contributes to the fire resistant qualities of the flue. Smoke, exhaust gases and other byproducts of combustion are transmitted from the fireplace to the outside atmosphere through the chimney flue.

It acts as a vent so that the byproducts of combustion do not find their way back into the room during combustion. This ensures that the household occupants are not endangered by inhaling these byproducts. Carbon monoxide poisoning can easily occur if exhaust gases are reversed back into the house. In transmitting the exhaust products of combustion outside, the flue allows the warmth from the fireplace to be retained indoors and benefit household occupants.

Furnace Flue Pipe

It is made of metal and is covered by an insulating material. It is usually pitched upwards towards the chimney. This allows the exhaust gases to move easily into the chimney and the outside atmosphere. Toxic gases produced during combustion are expelled from the house through the exhaust vent.

This prevents pollution by the furnace from taking place indoors. The exhaust pipe is also a vital safeguard against accidental fires. When exhaust gases are not properly expelled from the building, they can interact with other combustibles to cause a fire.

Water Heater Flue Pipe

A water heater flue pipe is a straight metal pipe fitted above the water heater burner, extending upwards. It is usually located centrally in the heater. Combustion gases are transmitted from the heater and expelled to the outside atmosphere. The safe release of toxic gases is a vital function of the water heater flue. It prevents pollution of air indoors. The flue helps to maintain a clean and safe indoor atmosphere during water heating operations. Carbon monoxide poisoning is prevented with a properly fitted flue.

The flue also plays a role in water heating. It acts as a heat exchanger which helps to heat water contained in the storage tank. The flue pipe must never slope downwards. This would discharge toxic gases back into the house and endanger household occupants.