The MARS 33247 Thermal Time Delay is a field-proven SPDT N/O sequencer designed for precision timing in residential and commercial HVACR systems. Engineered to handle high-current electric heat and air conditioning loads, this 24V control voltage relay utilizes a solid-state PTC device and a snap-acting disc to ensure positive make/break action. With a delay-on-make range of 1–24 seconds and a delay-on-break range of 15–75 seconds, this 33247 sequencer provides the necessary staging for blower motors and heating elements, effectively preventing duct shudders and circuit overloads. The vibration-resistant, non-positional design allows for versatile mounting inside any control panel, making it a reliable OEM replacement for various brands. This thermal time delay relay is ambient compensated to maintain timing accuracy regardless of the enclosure temperature, ensuring consistent performance in furnaces, heat pumps, and unit heaters. Key Benefits for the Contractor: Universal Compatibility: Works across gas furnaces, oil burners, refrigeration, and electric heat sequencers. Enhanced Reliability: The snap-action switch mechanism is shock and vibration resistant to prevent contact bounce. Precision Staging: Features a 1–24s "On" delay and 15–75s "Off" delay for optimized airflow management. Durable Construction: Rated for up to 25 Amps at 120/240V for heavy-duty switching applications. Field Ready: Compact, non-positional orientation simplifies installation in tight wiring compartments. Common Questions: Is the MARS 33247 compatible with 120V or 240V loads? Yes, while the control circuit operates on 24VAC, the SPDT contacts are rated to switch power circuits up to 240V, making it ideal for electric heating elements. Does this relay replace other brand sequencers? The 33247 is a standard SPDT 1 & 3 N.O. configuration that often replaces Klixon and other OEM thermal delays with similar timing and voltage specs. Can I mount this sequencer vertically or horizontally? Absolutely. The non-positional design ensures that the internal thermal mechanism operates accurately at any angle within the cabinet. 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.
