# Fresh air damper for combustion in conditioned attic



## jamalothmanrn (5 mo ago)

I'm in the process of installing in my attic open cell spray foam. I have an 85% efficiency trane dual stage furnace ( 3 years old). One of the installation installers mentioned that i need to add at least an 8" duct from my roof ofmr eve that terminates near the furnice flame box to provide enough O2 needed for combustion. He also suggested that i could add a damper that will automatically turn on when the furnace is ON, therefore keeping the place sealed when the furnace is off which will maximize the effect of a sealed space. I purchased the Honeywell EARD8TZ Round Fresh Air Damper, 8", And Damper 8" Round Professional-Grade (HVAC Zoning) - Preminum replacement for Honeywell, EWC. Any advice on which in is better? And how to wire it to my furnace to make them open ONLY when the furnace is ON. ?
Thank you


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