Do both vents need to be extended to the exterior? This is a Trane XR90 direct vent furnace. Yeah…the condensate drain is missing a trap.
No. As long as sufficient supply of combustion air is available at interior location.
What Chris said. I just had the same question come up on a new house inspection a few weeks ago. Here in NYC, combustion make up air must be brought in from outside the building, and if so, the furnace vent does not need to be run to the exterior. That is also okay per manufacturer specs.
from post 3
What Chris said. I just had the same question come up on a new house inspection a few weeks ago. Here in NYC, combustion make up air must be brought in from outside the building, and if so, the furnace vent does not need to be run to the exterior. That is also okay per manufacturer specs.
John,
You don’t sell carbon monoxide detectors by any chance do you
No but you should make sure there is a source of combustion make up air into the structure.
They have been required around here for over 30 years.
Yes the intake should be in the same air pressure envelope.(recommended no matter)
It helps to read the Install manuals which tell you this depending on model.
They should actually be between 18 inches and 36 inches apart.
The indoor air is often contaminated with cleaning or painting chemicals and you are also creating a negative pressure zone forcing you to calculate room size for ventilation.
The condensate is on a pump.
No, it is not necessary though some manufacturers may recommend it. While bringing in exterior air may mean you lose efficiency due to cold air feeding into the heat exchanger, drawing air from the inside would also reduce efficiency some by removing conditioned air out the flue. Both would be minimal.
There are advantages to having the combustion air come from the exterior. In a modern house with your setup pictured, the tight construction could mean air might be drawn in down the water heater flu causing poor drafting or ever putting out the pilot. This may be a greater problem in combination with bathroom vents a range hoods.
If you don’t provide a make up air source the unit will pull if from a open window, door or every crack in the building envelope.
Read again Cameron as some manufacturers do not just recommend it but insist.
Is it so hard to run it?
Stanley should be looking up the model.
You have a lot more problems with the water heater than that vent!
90+ furnaces are to be vented to the exterior according to manufacturer’s installation for efficiency.
Oops. meant makeup air. :neutral:
I know what you meant but David sure slipped up…lol
quote David…90+ furnaces are to be vented to the exterior according to manufacturer’s installation for efficiency.
Should we give him a hard time ?
I’m just trying to talk yous guys lingo!
Bob, you gave me grief about the Arrhenius equation the other day. Just trying to communicate at the same level… 
I am not engaging in that kind of behavior girls. Lol.
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