The Functional Devices TR40VA002 is a compact, high-performance 40VA transformer designed to supply reliable low-voltage power for HVAC controls, relays, actuators, and building automation equipment. Engineered for durability, this model converts 120V AC line voltage to a stable 24V output and includes dual 1/2-inch conduit hubs for quick, flexible installation in electrical enclosures or junction boxes.
Built for both residential and commercial applications, the TR40VA002 delivers consistent voltage under load, making it an excellent choice for powering thermostats, dampers, zone valves, safety circuits, and other 24-volt control devices. Its encapsulated coil design helps protect internal winding from dust and vibration, increasing longevity in demanding environments.
Whether used for equipment replacement, system upgrades, or new installations, this 40VA transformer provides dependable low-voltage power with a space-saving footprint and straightforward wiring layout. Installers appreciate its rugged construction, clean regulation performance, and versatility across a wide range of HVAC and automation systems.
Wiring Diagram:

| Power Rating | 40 VA |
|---|---|
| Secondary Voltage | 24 V |
| Primary Voltage | 120 VAC |
| Type | Class 2 Control Transformer |
| Approval / Compliance | UL Listed, Class 2 |
| Duty Rating | Continuous |
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