Recessed Can / LED Downlight

Related terms

• Recirculation Pump

  A pump delivering near-instant hot water at fixtures by keeping the line warm. Saves water; adds energy unless on a timer/demand control.

• Receptacle / Outlet

  The point devices plug into. Tamper-resistant receptacles are now code in dwellings; spacing rules govern how many a remodel must add.

• Refrigerant

  The working fluid that carries heat in an AC/heat pump. R-410A is being phased down to lower-GWP refrigerants (e.g., R-454B) under EPA ru…

• Radiant Floor Heat

  Warming a space via tubing or electric mats under the floor. Even, comfortable heat; best designed in during a remodel when floors are open.

• Register / Grille

  The supply outlet (register, with damper) and return inlet (grille) terminating the duct in each room.

• Plenum

  The main air chamber off the furnace/air handler from which supply ducts branch and into which the return delivers.

• Return Air

  Ducting that draws room air back to the system. Insufficient return is a common cause of weak airflow and short-cycling.

• PEX

  Cross-linked polyethylene supply tubing — flexible, freeze-tolerant, fast to install with fewer joints. The dominant modern repipe material.