Four Seasons 35866 HVAC Cut-Off Switch

Four Seasons 35866 HVAC Cut-Off Switch

The Four Seasons Pressure Switch 35866 is a system-mounted HVAC cut-off switch built for low-pressure circuit control in automotive air conditioning systems. It uses a wire lead connector, a 2-terminal layout, and a female 7/16 in. x 20 fitting for direct pressure-switch service.

Compatible With HVAC systems on select vehicle applications, this Four Seasons pressure switch is a practical replacement when diagnosing compressor cut-out concerns on Honda Civic and similar make/model applications that use this style of low cut-out switch. The Four Seasons Pressure Switch line focuses on pressure-based control components for HVAC service work.

Key Features

• Part number 35866 from Four Seasons Pressure Switch
• Low cut-out HVAC pressure switch for system-mounted applications
• Wire lead connector with 2 terminals
• Female fitting with 7/16 in. x 20 thread size
• Black plastic and metal construction
• Open circuit configuration
• Meets or exceeds OEM requirements

Detailed Description

Four Seasons 35866 is an HVAC cut-off switch used to monitor system pressure and open the circuit when pressure drops below the specified threshold. That function helps protect the air conditioning system from operating under low-pressure conditions that can affect compressor performance and refrigerant circuit operation. The system-mounted design and wire lead connection make it a direct-fit style service part for vehicles that use this pressure-switch configuration.

This part cross-references FEL-PRO 35866 for the same application. When replacing a pressure switch on a Honda Civic or other vehicle with the same low cut-out setup, confirm the fitting thread, connector style, and switch type before installation. The 35866 part number is also commonly searched as Four Seasons 35866 HVAC cut-off switch.

Common Problems This Part Can Address

• Compressor cycling off because the low-pressure circuit is opening
• Air conditioning system shutdown caused by a faulty pressure switch
• Intermittent HVAC operation from worn switch contacts
• Incorrect pressure signal to the A/C control circuit
• Service replacement for a damaged wire-lead pressure switch

Installation Notes and Tips

Verify the fitting thread size, connector style, and switch type against the original component before installation. Inspect the HVAC system for refrigerant loss or pressure-related faults before replacing the switch, since low pressure conditions can trigger cut-out operation. Use proper service procedures for the vehicle’s A/C system and confirm the connector seats securely on the wire lead terminals.

Quality Assurance

Four Seasons lists this pressure switch as meeting or exceeding OEM requirements, making it a suitable replacement for pressure-controlled HVAC service on select applications. Part number 35866 is built with plastic and metal materials for system-mounted use in automotive air conditioning circuits.