How new furnaces vent.
Can high efficiency furnace vented through chimney.
The condition of the chimney is a factor because new super efficient gas furnaces do not vent up the chimney.
If your furnace has an afue rating below 90 percent it will most likely have a flue pipe that goes up through your roof.
But it is not advisable.
I think don t it is possible to vent a 95 efficiency furnace up through an existing chimney.
In contrast modern high efficiency condensing furnaces exhaust much cooler gasses and need only plastic pipe materials such as pvc cpvc or abs for their exhaust vents.
I believe high efficiency furnances must be vented horizontally through a wall.
Two depending upon where the inlet for furnace combustion air intake pipe is located in relation to the fireplace chimney it could pull fireplace combustion gases and smoke into the furnace.
They include a second heat exchanger that reclaims additional heat from the system s exhaust gases before they are vented away.
Condensing gas furnaces achieve their high levels of efficiency by adding another step to the fuel burning and venting process.
For these reasons exhaust from a condensing furnace should never be vented through a standard chimney.
They are vented outdoors horizontally through a wall by a small plastic pipe.
To combat this issue a high efficiency condensing furnace uses pvc pipes to extract the acidic water from your home.
I have not heard of high efficieny only lasting 10 13 years.
Additionally how do you seal furnace exhaust to chimney.
High efficiency furnace venting uses two heat exchangers.
The venting system is installed at the same time as your high efficiency furnace.
In fact we almost always recommend against it if you have an older chimney and a new high efficiency furnace.
These are connected to the furnace and routed out to the side of your home.
The exhaust gas is too cool for it to rise.
Traditional gas fired forced air furnaces produce hot combustion exhaust gasses and therefore need metal vent pipes or chimneys.
The efficiency rating of a furnace is called afue annual fuel utilization efficiency.
That depends on whether you have a standard efficiency or a high efficiency furnace.
The heater pipe is normally level and moderately short.
If your furnace has an afue rating of 90 percent or above it will have a flue pipe that goes out of the side of your house.
In standard furnaces all these combustion gases including carbon monoxide are usually vented through chimneys or flues.
Also the acidic elements in the exhaust can damage unprotected chimney bricks and mortar.
As usual new furnaces vent through a pipe that goes from the unit straight out the side of the home.
You may want to look into simply having the pvc intake and exhaust pipes for the furnace rerouted to go through a sidewall in your basement to the exterior.
Sometimes we see multiple appliances using the same flue vent system for multiple appliances but this isn t always a possibility.
Conventional furnaces use only one they use a two stage process.
I would be very leary of a hvac contractor would not do this.
Brush away any dirt or dust from the area around the furnace vent that you will be sealing.
