Johnson Controls T26S-18 Thermostat

The Johnson Controls T26S-18 is a heavy-duty line voltage wall thermostat engineered for precise control in both heating and cooling applications. This SPDT thermostat features a rugged bimetal sensing element to ensure accurate temperature regulation within a 40?F to 90?F range. Designed for high-amperage electric heat or fan coil units, it operates without an external selector switch, relying on its internal switching logic to manage loads. Technicians frequently utilize the T26S-18 as a direct replacement for the Powers 134-1084, offering the same footprint with updated Johnson Controls internal components. The unit provides a fixed 1-3/4?F heating differential and a 2-1/4?F cooling differential, preventing short-cycling and ensuring equipment longevity. Its knob adjustment interface allows for reliable setpoint changes in mechanical rooms, warehouses, and commercial spaces where digital complexity is a liability. For contractors performing an HVAC thermostat replacement, the T26S-18 delivers a mechanical solution that withstands the rigors of industrial 120V or 240V systems.

Key Benefits

• Universal SPDT Switching: Capable of controlling motors or heaters with a single-pole, double-throw contact configuration.
• Mechanical Reliability: Eliminates the need for batteries or complex programming, reducing callbacks in demanding environments.
• Optimized Differentials: High-precision mechanical action maintains tight environmental control while protecting compressor and heating elements from frequent cycling.
• Drop-in Legacy Compatibility: Specifically engineered to replace the Powers 134-1084, ensuring seamless retrofits without mounting modifications.

Common Questions

Is the T26S-18 compatible with 277V circuits?
Yes, this model is rated for line voltage applications including 120, 208, 240, and 277 VAC, making it a versatile stock item for commercial portfolios.

How do I wire this for a cooling-only application?
When utilizing the T26S-18 for cooling, wire to the "R" and "Y" (or equivalent cooling) terminals; the SPDT switch will close on temperature rise.

Can this thermostat be used to control a line voltage fan motor directly?
Absolutely. Provided the motor's full load amperage (FLA) does not exceed the contact ratings (typically 16A at 120V), it can handle direct motor loads.

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.