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Side Wall Venting 80% Gas Furnace
I have my furnace in an enclosed space off the side of my balcony, so it’s not inside the living quarters. There is a large opening (with filter) in the wall between my living room and the outside enclosed space.
First question: If there is backdrafting, will CO come into my living room through that filtered opening?
The existing furnace is 20 years old and needs to be replaced. It is side wall vented WITHOUT a power venter. The previous owners were obviously not poisoned by CO during that 20 years.
Next question: Why do I need to add a power venter on the new furnace?
The new furnace is American Standard 80% fan assisted (induced draft blower).
The installation guide says, “IF DESIRED (my caps), a side wall termination can be accomplished through the use of an add-on draft inducer.”
“If desired” doesn’t sound like something that must be done.
Also, the install guide says, “EXCESSIVE COMBUSTION VENT PRESSURE OR FLUE BLOCKAGE. If pressure against the induced draft blower outlet becomes excessive, the pressure switch will shut off the gas valve until acceptable combustion pressure is again available.”
To my understanding, this means that if a backdraft condition occurs, the furnace will not run.
So how does the absence of an add-on power venter create a safety risk? The furnace already has a safety pressure switch.
Wouldn’t the power venter be needed only in the case of the furnace failing to fire because of the existing safety sensor being activated on a regular basis?
I’m not an HVAC guy. I’m just a regular guy finding conflicting information, and I’m trying to understand why some people say the power venter MUST be used with side wall venting.
Seems like it would only be necessary if the furnace keeps shutting down.
Any comments would be much appreciated…