Resideo - Honeywell Home AT72D1683 Standard Transformer

The AT72D1683 Standard Transformer, a Resideo/Honeywell Home product, delivers reliable 24V control power for residential combustion systems. It accepts 120V AC input and provides 24V AC output with a 50/60 Hz rating and a 40 VA power rating, ensuring smooth operation of your thermostat, gas valve, and relay components. Ideal for upgrading older controls or integrating new installations, its robust design helps maintain a steady 24V supply for ignition sequencing and safety interlocks, even in demanding home environments.

Designed for durable installation, the transformer features a NEMA Type D enclosure and compact dimensions (2-7/32 in W x 3-1/16 in D x 3-7/32 in H). It mounts easily with a mounting foot, plate, or clamp, and is well suited for residential combustion control systems in compact equipment bays or cabinet installations.

UL and CSA approved for safety and reliability. This model includes essential accessories—thermostat, gas valve, and relay—so you can wire quickly and start testing sooner. With Resideo's engineering, you get compatibility with standard residential controls and dependable performance across typical 50/60 Hz infrastructure.

• Primary Voltage: 120 VAC
• Secondary Voltage: 24 VAC
• Frequency: 50/60 Hz
• Power Rating: 40 VA
• Temperature Rise: -20 to 105 Deg F
• Enclosure: NEMA Type D
• Size: 2-7/32 in W x 3-1/16 in D x 3-7/32 in H
• Mounting: Foot/Plate/Clamp
• Application: Residential Combustion Control System
• Approvals: UL, CSA
• Includes: Thermostat, Gas Valve, Relay