Hello! Some of you are familiar with my previous posts of trying to resolve EXCESSIVE dust in a 1-yr-old home. I have followed much of your advice from the past, but the problem persists, so I am seeking more help.
problem: dust accumulates within hours of cleaning (year-round)...LOTS of dust, in excess of normal house dust. 3 story house with 3 heating and air units, dust primarily on main floor. No carpet, hardwood floors with 1 area rug, leather furniture, no draperies.
things we have done:
*all ductwork has been thoroughly inspected and sealed after being diagnosed leaky (includes removing drywall ceiling to access ductwork of main unit)
*ductwork has been vacuumed and does not appear to be the source as supply registers stay relatively clean
*sealed all penetrations we could find from conditioned to unconditioned space (plumbing, electric, can lights, bath fans, attic accessses, even caulked below quarter-round baseboard trim)
*We had a blower-door test that showed our infiltrations to be "within normal limits" even before some of our improvements (I know WNL doesn't tell you much, but I can't get the readings from our RECC who conducted the test.)
*I am now considering make-up fresh air, but wonder if it would improve the dust problem. We have 2 direct-vent fireplaces, but they are very seldom used. We also seldom use the bath fans and have no kitchen fan. The water heater and heating and air units are electric except for gas conversion on main unit. We have a gas range-top. I do operate the electric clothes drier almost daily (dust accumulates even on the days I don't). Since we have few combustion products, I wonder would the make-up air be of benefit?
*Now that our duct-work is well sealed, why isn't the air handler acting as a whole-house filter and eliminating the dust? We have a MERV 8 4" pleated filter that has been inspected and found not to have any bypass evident.
*Just another thing I've noticed that I wonder if it is normal or might be a clue--our house holds quite a bit of heat. I keep the thermostat set on 76 and even on nights when the temperature drops 20 degrees, the house temp. never falls below 76.
Thanks in advance for any help you may have!!