Schneider Electric (Barber Colman) 21-933-1 Cover

For field technicians maintaining legacy pneumatic systems, the Schneider Electric (Barber Colman) 21-933-1 Cover provides a standardized replacement solution for aging or damaged thermostat faces. This gray plastic cover is engineered as the direct successor for a wide array of vintage components, including the 21-933, 21-934, 21-939, and high-frequency units like the CT-12 and CT-921. Designed for 2x2 dial-type pneumatic room thermostats, it features integrated Fahrenheit (°F) and Celsius (°C) markings to ensure clear setpoint visibility and precise calibration across diverse facility standards.

Replacing brittle or illegible covers is essential for preventing unauthorized setpoint tampering and protecting internal pneumatic internals from particulate ingress. This OEM-spec cover integrates seamlessly with existing Schneider Electric pneumatic thermostats, such as the 2212 and 2211 series. By consolidating multiple legacy part numbers like the C3-42 and 2890-010 into a single 21-933-1 model, contractors can streamline inventory while ensuring exact fitment on historic Barber Colman control systems. The gray thermostat cover maintains a professional aesthetic in commercial environments while providing the durable protection required for long-term mechanical reliability.

Key Benefits

• Universal Compatibility: One-to-one replacement for over 20 legacy Barber Colman and Schneider Electric part numbers, simplifying truck stock.
• Dual Temperature Scales: Integrated Fahrenheit and Celsius markings support global standard compliance and intuitive technician adjustments.
• Pneumatic System Protection: Shields sensitive 2x2 dial-type thermostats from dust, debris, and accidental setpoint changes.
• Technical Precision: Specifically molded for Schneider Electric thermostat controls to ensure no interference with dial rotation or thermometer readings.

Common Questions

Which legacy models does the 21-933-1 cover replace?
This unit is the direct updated version for models 21-933, 21-934, 21-939, 21-964, 22-823, 22-833, 22-923, 22-933, 22-939, 2890-010, 2890-011, C3-26, C3-42, C3-X62, C4-47, CT-12, CT-21, CT-921, and CTR-921.

Does this cover include the internal thermostat mechanism?
No, the 21-933-1 is the replacement gray cover only. It is designed to be installed over existing pneumatic thermostat assemblies to restore markings and protect the interface.

Are there specific tools required for installation?
Installation typically requires standard HVAC hand tools. It is designed to snap or screw into place depending on the specific Barber Colman thermostat base being serviced.

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.