AFCI

Related terms

• 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…

• 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.

• Air Admittance Valve (AAV)

  A one-way vent valve allowing air in without a roof penetration, useful for islands and additions where running a vent is impractical (wh…

• 240-Volt Circuit

  A higher-voltage circuit for ranges, dryers, EV chargers, and heat pumps. Adding one often needs panel space and a dedicated run.

• 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.

• Aluminum Branch Wiring

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

• Amperage / Service Size

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

• Anode Rod

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