Transformer 40VA 120/208/240V to 24V Replacement – NBK-20604

Transformer 40VA – 120/208/240V to 24V Replacement – NBK-20604 The NBK-20604 Transformer is a reliable replacement component used in HVAC systems requiring a 40VA step-down transformer to convert high-voltage input into a stable 24V output. This transformer replaces Mars 50354 and is also compatible with Packard PF42440, making it an ideal solution for restoring proper low-voltage power to thermostats, relays, and control boards. Key Features 40VA Power Rating: Suitable for many HVAC control applications Multi-Voltage Input: Supports 120V, 208V, and 240V primary connections 24V Output: Provides consistent low-voltage power for system controls Direct Replacement: Replaces Mars 50354 and Packard PF42440 HVAC Ready: Designed for furnaces, air handlers, and other control circuits Specifications SKU: 20604 Category: HVAC, Miscellaneous OEM Brand: Mars Replaces OEM: 50354 Voltage: 120/208/240V Primary → 24V Secondary Rating: 40VA Direct Replacement For Mars: 50354 Packard: PF42440 Why Choose NBK-20604? The NBK-20604 Transformer ensures dependable low-voltage power delivery for HVAC control systems. It’s an essential replacement when troubleshooting power loss to thermostats, relays, or ignition/control boards. Installation Tips Turn off all power at the breaker before installation. Confirm input voltage matches your system wiring (120V, 208V, or 240V). Secure transformer mounting to reduce vibration and wear. Check for proper 24V output before restoring full system operation. Consult a licensed technician if wiring is uncertain. Pairs Well With Thermostats, Control Boards, Ignition Modules, Limit Switches, HVAC Relays SPECIAL ORDER NOTICE: This item is sourced through our special order program. Please allow 1–2 business days for processing prior to shipment.