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ventilating after weatherization
Question on what cfm needed to provide adequate ACH following weatherization/insulation.
before = 2100 cfm @ -50Pa
after = 1400 cfm @ -50Pa
Building volume including basement 25.3k ft^3
Numbers I'm getting from ASHRAE 62-89 not particularly helpful, other than showing there should be supplemental ventilation. Have programmable, var spd fan. Not sure what to set it for.
On a hydronically-related note, the supply temps used for a given load have dropped by about 12-15% (smart control system using ODR/IDF).