Honeywell Home ARD18TZ/U 18 in Round Automatic Damper

The ARD18TZ is an automatic round zone damper from Honeywell Home, 18 in, 24 V.

In a forced-air zoning system the damper is the moving part. The zone panel opens the dampers for the zones that are calling, keeps the rest shut, and runs the equipment — so one furnace serves an upstairs that wants cooling and a basement that wants nothing without either room getting the other one’s air.

Power closed, spring open. The actuator drives the blade shut and a spring returns it open, so a damper that loses power or loses its actuator fails open. The zone may lose control, but the blower never ends up pushing against a duct that is sealed off — which is the failure that breaks things.

Size it by duct diameter, and count the total 24 V load before adding dampers to an existing panel. Every actuator draws while it drives, and a transformer that was adequate for three zones is not automatically adequate for five.

The actuator mounts side or top, which is what makes it installable in a joist bay where the pipe can only be reached from one side.

• Brand: Honeywell Home
• Manufacturer Part #: ARD18TZ/U
• Type: Automatic round zone damper
• Size: 18 in
• Shape: Round
• Voltage: 24 V
• Damper type: Single-blade, round
• Actuator mounting: Side or Top
• Motor: Power closed, spring open
• Terminals: M1-Power; M6 Common; M4 (optional)-LED indication
• UPC: 085267707497
• Category: Zone Dampers