Your furnace has
a vent system
so that it can “inhale” air to create clean and efficient combustion. This vent system is also where your furnace will “exhale” the combustion by-products.
Where does combustion take place in a gas furnace?
In gas furnaces and gas heaters there are burners that mix and burn fuel in
a combustion chamber surrounded by a heat exchanger
. The heat exchanger picks up heat from the flame and burning gases in the combustion chamber and transfers that heat to a heating fluid (air, water or steam).
Where does combustion happen?
Combustion is a technical term for burning, which is a chemical process that occurs
when a fuel reacts with an oxidant to produce heat
. Some common examples of combustion include burning wood to heat a home, the burning of petrol to run a car and the combustion of natural gas to cook on a stovetop.
Where does furnace combustion air come from?
Most high efficiency furnaces get their combustion air
directly from the outside
. This is the best and most efficient way to do it. If your furnace has two PVC pipes going to the outside, then one of those pipes is taking the flue gases out and one is bringing fresh air in for combustion.
Do furnaces use combustion?
The highest performance combustion furnaces are sealed-combustion, direct-vent, condensing gas furnaces, with an Annual Fuel Utilization Efficiency (AFUE) exceeding 94%. … Forced air furnaces are the most common heating source in America (EIA 2009). Forced air furnaces are typically fueled by natural gas.
Why do gas furnace efficiencies jump from 80 percent to 90 percent?
Why do gas furnace efficiencies jump from 80% to 90%? Efficiencies over 80%
cause condensation
but the flue gas is still too hot for PVC vent pipe until the efficiency reaches 90%.
Do natural gas furnaces need a chimney?
Gas Appliances and Your Masonry Chimney. … But many don’t realize that a gas heating appliance – whether it is a furnace, boiler or even a water heater – relies
on the chimney for proper venting of the exhaust
.
What are the 2 types of combustion?
2 Types of Fire. Combustion is applicable to two types of fire:
Flaming combustion and smoldering combustion
[13].
What are the 4 products of combustion?
- Carbon Dioxide.
- Carbon Monoxide.
- Sulfur Dioxide.
- Nitrogen Oxides.
- Lead.
- Particulate Matter.
What is combustion of fuel?
Combustion is a complex series of chemical reactions, but from a physical standpoint may be described as the
rapid combination of oxygen with a fuel
, such as natural gas or wood, resulting in the release of heat. Most fuels contain carbon and hydrogen, and the oxygen usually comes from air.
How much combustion air do you put in a furnace?
A furnace must be supplied a specific amount of fresh air per cubic foot of gas burned. To burn 1 cubic foot of gas, approximately 1,000 Btu for natural gas, requires
10 cubic feet of air
for perfect combustion (Figure 2).
What is combustion air for a furnace?
What is combustion air? Combustion air is
a source of oxygen needed to burn fuel such as natural gas or liquid propane (LP)
. You can’t produce a flame in a furnace without proper combustion air. The image above shows the combustion air as a vent in the garage to pull air from the attic.
How much ventilation does a furnace room need?
According to the Uniform Building Code, which provides regulatory guidelines for building design and construction, to be safe, even a partially enclosed room with a direct-vent furnace requires a
minimum of 50 cubic feet of volume for every 1,000 BTUs of fuel input.
How do I know if my furnace is sealed combustion?
When we say a furnace is “sealed combustion,” it means
it draws on air from outside the house to use for burning fuel (i.e. combusting fuel)
. The jets of the burners in a gas furnace must have air to mix with the gas, and in the standard “atmospheric furnace,” this air comes from within the house.
How do I know if my furnace has sealed combustion?
An atmospheric is the standard natural gas furnace of the past few decades. Essentially, if you can
look inside your furnace and see the blue light of the flames on the burners when the system is running
, you have an atmospheric combustion furnace.
How do you tell if your furnace is venting properly?
How Do I Know If My Furnace Isn’t Venting Properly?
Gas furnace fumes are moist
, so if you notice “sweat” on your windows, this is a sign that your furnace isn’t venting correctly. When your furnace comes on in the morning, if it is venting into your house rather than outdoors, moisture will condense on the cold glass.
