ICM Controls ICM253 Timer

The ICM253 Timer is a precision-engineered post-purge fan delay timer designed for 18-30 VAC control circuits. This solid-state control is critical for maintaining high system efficiency by ensuring the indoor blower continues to circulate air after the thermostat is satisfied. Featuring an adjustable off-delay range from 12 to 390 seconds, it provides technicians with the flexibility to fine-tune HVAC blower motor timing based on specific ductwork configurations and residual heat/cool recovery needs. Built to withstand the rigors of frequent cycling, this control is a direct replacement for part number 46144700, ensuring a seamless fit for legacy equipment. The low-voltage fan control logic prevents short-cycling and improves overall occupant comfort. By extracting maximum thermal energy from the heat exchanger or evaporator coil, the ICM Controls delay board reduces mechanical stress on the primary equipment while optimizing energy consumption. Its compact footprint and standard spade terminals allow for rapid field installation during service calls or retrofits.

Key Benefits for Technicians:

• Precise Delay Control: The adjustable off-time potentiometer allows for custom settings between 12 and 390 seconds to match OEM specs.
• Universal Compatibility: Operates on standard 24V HVAC control circuits, making it a versatile tool for your service truck.
• Drop-In Replacement: Specifically designed to replace 46144700 units without requiring wiring modifications or additional mounting hardware.
• Solid-State Reliability: Eliminates moving mechanical parts within the timing circuit to ensure consistent performance in high-duty cycle applications.
• High Current Capacity: Rated to handle typical inducer or blower relay loads found in residential and light commercial air handlers.

Common Installation Questions:

Is this timer compatible with both heating and cooling modes?
Yes, the ICM253 is designed to interface with the G-terminal circuit, allowing for post-purge functionality across different seasonal modes depending on your wiring configuration.

What happens if the 24V power is interrupted during the delay cycle?
As a post-purge fan delay, the unit requires a constant R-connection to maintain the timing sequence if the thermostat signal is removed prematurely.

How do I accurately set the delay time?
Rotate the on-board dial to the desired second mark. We recommend testing the cycle with a stopwatch during commissioning to ensure the fan delay interval meets the specific airflow requirements of the plenum.

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.