White-Rodgers S84-11 Transformer

The White-Rodgers S84-11 Transformer is a heavy-duty 120V to 24V step-down transformer engineered for reliable performance in demanding residential and light commercial HVAC applications. As a Class 2 energy-limiting transformer, this 40VA-rated model provides a stable secondary output of 24VAC, making it the industry standard for powering gas valves, 24V thermostats, fan controls, and relay centers. Its universal mounting design—supporting plate, foot, or hub installation—ensures seamless integration into existing control panels or equipment enclosures. Field-proven for its durability, the White-Rodgers S84-11 features 10-inch primary leadwires and secondary screw terminals for secure electrical connections. The unit is designed to remain unaffected by momentary short circuits and is rated for ambient temperatures up to 150°F, providing the thermal resilience required for furnace and boiler environments. When replacing failing 40VA transformers, the S84-11 offers the technical consistency and HVAC control circuit safety compliance that professional contractors demand.

• Universal Compatibility: Multi-mount configuration facilitates plate, foot, or hub mounting for maximum field flexibility.
• Energy Limiting Performance: Inherently limited design protects against short circuits, preventing fire hazards during secondary faults.
• High Temperature Resilience: Reliable operation in high-heat environments with a maximum ambient rating of 150°F.
• Secure Terminations: Combined 10-inch primary leads and secondary screw terminals ensure low-resistance connections.
• Versatile Application: Ideal for 24VAC control systems, including humidifiers, electronic air cleaners, and zone valves.

Can I use the White-Rodgers S84-11 to replace a lower VA transformer?
Yes, you can safely use a 40VA transformer to replace a 20VA or 30VA unit, provided the voltage ratings (120V primary/24V secondary) match. The 40VA rating indicates the maximum power load the transformer can handle without overheating.

Does this transformer include a circuit breaker or manual reset?
The S84-11 is an inherently limited Class 2 transformer, meaning it does not require a manual reset. It is designed to withstand momentary shorts and will protect the circuit through its internal impedance.

What is the difference between the S84-11 and the S84Z-90?
While both are 40VA universal transformers, the S84-11 is a dedicated 120V primary model. The S84Z-90 is a multi-tap version that supports 120V, 208V, or 240V primary inputs. Always verify your line voltage before installation.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.