Air Admittance Valve (AAV)

Related terms

• Permit

  Official jurisdiction authorization to perform regulated work, triggering required inspections. Unpermitted remodels can force teardown,…

• Air Handler

  The blower unit moving air across the coil and through the ducts, paired with a heat pump or as part of an electric/hydronic system.

• AFUE

  Annual Fuel Utilization Efficiency — the percent of fuel a furnace converts to usable heat over a year. 80% is mid-efficiency; 90–98% is…

• Aluminum Branch Wiring

  1960s–70s aluminum branch circuits prone to connection overheating. Requires approved remediation (e.g., COPALUM/AlumiConn) for safety.

• AFCI

  Arc-Fault Circuit Interrupter — detects dangerous arcing that can start fires. Code now requires it on most living-space circuits; remode…

• Amperage / Service Size

  The home's total electrical capacity (commonly 100A, 150A, 200A). Kitchens, EV chargers, and heat pumps often force a 200A upgrade.

• ABS / PVC DWV Pipe

  The black (ABS) or white (PVC) plastic pipe used for modern drain and vent lines. Local code dictates which is allowed.

• Anode Rod

  A sacrificial rod inside a tank water heater that corrodes instead of the tank. Replacing it periodically greatly extends heater life.