Description
The S1-024-21218-700 is a 24-volt Single Pole Single Throw (SPST) relay made by York, designed for HVAC systems. This relay acts as a control switch inside a furnace, air handler, heat pump or air-conditioning unit, allowing low-voltage (24 V) control circuitry (from a thermostat or control board) to switch higher-power circuits — e.g. turning on blower motors, fans, or other components — safely and reliably.
Key Features
- Part Type: 24 V SPST Relay (single-pole, single-throw)
- Control Voltage: 24 V AC, 60 Hz — standard for most residential HVAC control circuits.
- Function: Switches electrical circuits (e.g. blower motors, fans, other loads) in response to a 24 V control signal — enabling safe control of higher-power components from low-voltage controls.
- Common Uses: Furnaces, air handlers, heat pumps, AC units — any system where a control signal needs to drive a motor, fan, or other high-power component via a relay.
- OEM Quality: Genuine replacement part — ensures compatibility and reliability compared to aftermarket or generic relays.






