Buffalo winters are hard on HVAC systems. The furnace runs constantly for months, snow and ice block exterior dryer vents, and closed-up homes concentrate dust and dander.
Best time to clean ducts in Buffalo: late fall (before the furnace runs 24/7) or early spring (before allergy season). Both let you start a heavy-use season with a clean system.
Dryer vents deserve special attention. Snow drifts against exterior walls can seal the vent flap shut. If your clothes are taking longer to dry in January than they did in October, the vent is probably restricted.