Do natural gas furnaces need a chimney? But while most homeowners are aware of the need to have their fireplace or woodstove chimneys cleaned and inspected, many don't realize that a gas heating appliance – be it a furnace, boiler, or even a hot water heater – also
relies on a chimney for proper venting of the exhaust
.
Can you vent a furnace without a chimney?
Two or more appliances could vent into an exterior chimney, but design conditions must be appropriate along with appliance fuel input
. Additionally, one of the appliances must have a draft diverter (natural draft system). Interior chimneys typically benefit from the heat of the structure.
Do new furnaces need chimney?
Chimneys in most homes are sized for a furnace and a water heater. But
when an old furnace is replaced by a high-efficiency furnace, the new furnace is typically vented through an outside wall instead of through the chimney
.
Do gas furnaces need to be vented?
Does a gas furnace need a chimney liner?
Draft & Efficiency
When it comes down to it, you need your furnace functioning as efficiently as possible to ensure you get the warmth and comfort you need this winter.
Liners can help direct gases up and out of your flue, so your system works better and faces less decay and deterioration
.
Can you vent a gas furnace through a wall?
Direct Vents
These furnace vents can be installed horizontally through an exterior wall
, or vertically so exhaust fumes go out through the roof. Although more costly than a natural vent, a direct vent is also a more efficient and safer option.
What is the code for venting a gas furnace?
503.6.
A gas vent shall terminate in accordance with one of the following: 1. Gas vents that are 12 inches (305 mm) or less in size and located not less than 8 feet (2438 mm) from a vertical wall or similar obstruction shall terminate above the roof in accordance with
Figure 503.6. 5
.
Do I need a chimney liner for a 80 gas furnace?
Older, less efficient furnaces do not need a chimney liner
. This is because the steam they release can be up to 700 degrees Fahrenheit. That means that the steam uses the entire space of the chimney as it travels outwards. More efficient furnaces, such as those at 80% AFUE, use the chimney for ventilation as well.
Do high efficiency furnaces use chimney?
Higher efficiency furnaces do not let out steam that is so high in temperature.
A really high efficiency unit (90% and above) does not even use the chimney
! They have their own plastic pipes that leave the home from the side of the house because the steam is only about 150 degrees.
How do you vent a high efficiency gas furnace?
To avoid this problem, high efficiency furnace venting requires the
use of PVC pipes instead of metal pipes to remove the acidic condensate from your home
. These PVC pipes are connected to the furnace and expelled outside. This high efficiency venting system must be installed when you install the new furnace.
Where do gas furnaces vent?
Old furnaces tend to be furnaces with standard-efficiency ratings. These furnaces vent gas
away from your house through a flue pipe
. The flue pipe is attached to the heat exchanger, where the gas combusts and produces heat energy. Gas exits the house through the exhaust pipe, which usually leads up to a house's roof.
How do you vent a natural gas heater?
Can a furnace be in a closed room?
Does a furnace room need ventilation? Most new building codes require that spaces that house gas-fired appliances such as water heaters and furnaces have an outside ventilation source to provide combustion air.
Electric Furnaces or water heaters do not need ventilation to support combustion
.
Does chimney need to be lined for gas fireplace?
Whether you go from gas to wood burning or vice versa,
you must install a new chimney liner appropriate for that type of fuel and use
. The same rule applies to heating and hot water equipment because different materials are more suited for different types of fuel.
Do you really need a chimney liner?
A chimney liner is therefore vital in the prevention of chimney fires that occur as a result of overheating in the chimney
. A chimney liner promotes better energy efficiency, because it helps the fire to burn brighter while minimizing loss of heat. It helps in maintaining an optimal air flow within the chimney.
How often should you clean your gas furnace chimney?
The National Fire Protection Assoc. 211 codes state that “chimneys must be inspected and cleaned
if needed annually
” – just like the oil service man services the furnace annually, so should the chimney system be serviced annually.
Can a gas furnace be vented out the side of the house?
An 80% efficient furnace CAN be side wall vented per National Fuel as Code 7.3. 4 with the use of a “mechanical draft system of either forced or induced draft design”
.
Does a furnace vent through a chimney?
Your furnace won't exhaust gases into your chimney anymore
. Instead, an HVAC contractor will install the system to expel the exhaust directly outside your home.
How far can you run a furnace exhaust?
How far above the roof should a gas vent be?
Gas vents shall extend
at least two feet
above the highest construction, such as a roof ridge, parapet wall, or penthouse, within ten feet of the vent outlet whether the construction is on the same building as the chimney or on another building.
How close can a gas furnace vent be to a window?
The vent terminal shall be at least 12-inches below, 12-inches horizontally from, or
12-inches above
, any door, window, or gravity air inlet into a building.
How do you vent a furnace through the roof?
How much does a chimney liner cost?
What is the use of chimney in furnace?
A chimney is an architectural ventilation structure made of masonry, clay or metal that
isolates hot toxic exhaust gases or smoke
produced by a boiler, stove, furnace, incinerator or fireplace from human living areas.
Can high efficiency furnaces be vented through the roof?
Does you need cold air return with high efficiency furnace?
Since high efficiency furnaces draw air directly from outside,
the furnace itself does not require a fresh air intake
in order to replace inside air that otherwise would have been drawn from the room the furnace is located in.
Why is a metal vent often preferred rather than a masonry chimney?
Why is a metal vent often preferred rather than a masonry chimney?
Metal vents reach operating temperatures quicker than masonry vents do
. Masonry chimneys tend to cool the flue gases.
Can you vent a gas furnace with PVC?
Where is my furnace vent located outside?
Is a 95 efficiency furnace worth it?
How are new furnaces vented?
Sidewall Venting
(High efficiency appliances)
This type of venting uses a 1 or 2 pipe system. An intake and an exhaust pipe are run separately and can be placed through almost any exterior wall, so they provide greater placement flexibility for a new furnace.
Does a gas furnace have an exhaust?
How safe are natural gas furnaces?
Gas Heaters Are Safe to Use
The main concern with a gas heater is the leak of carbon monoxide, which is a toxic byproduct of the combustion of gas. Furnaces vent out CO through a flue, and there is very little chance that it will flow into the house.
What is a direct vent natural gas heater?
For clean, comfortable heat when and where you want it,
the gas flame is completely sealed inside, away from all contact with room air
. Air necessary for combustion is drawn into the chamber from outside through the vent and combustion products are vented directly to the outside.
What is a non direct vented furnace?
A non-direct vented furnace
takes all air for combustion from the room in which furnace is installed
. Non-direct venting requires only one pipe for venting the flue gases to the outdoors but you must make sure there is enough air for combustion and ventilation.
How does a vent free natural gas heater work?
Ventless gas heaters are room-heating furnaces that do not vent air to the outside of the house. Instead, the oxygen that is needed to fuel the combustion process for heat is taken from the air inside of the room in which the unit is placed, and the resulting heat is vented back out directly from the unit.
