Bohn 5709l Defrost Thermostat 3-wire Refrigeration

Product Description

The BOHN 5709l is a defrost thermostat designed for use in refrigeration systems such as unit coolers and evaporator coils. It monitors coil temperature and controls the defrost cycle by opening and closing at set temperature thresholds, helping prevent ice buildup and maintain efficient system operation. The thermostat features a 3-wire lead configuration with a lead length of 17 inches and is built with a combination of plastic and stainless steel construction. It closes at 35 degrees F and opens at 55 degrees F, providing a reliable operating range for standard low-temperature refrigeration applications. This component is typically installed by refrigeration technicians and commercial HVAC-R service professionals.

The BOHN 5709l is suited for commercial and light-industrial refrigeration equipment where automatic defrost control is required. It is commonly installed on evaporator coil assemblies in walk-in coolers, reach-in cases, and unit cooler systems. The 3-wire lead design accommodates standard defrost control wiring configurations found in these applications. Its compact sensor body and stainless steel material make it appropriate for the wet, low-temperature environments typical of refrigeration coil compartments.

Key Features

• Opens at 55 degrees F and closes at 35 degrees F for precise defrost cycle control
• 3-wire lead configuration with 17-inch lead length for flexible installation routing
• Stainless steel and plastic construction suited for cold, humid refrigeration environments
• Compact sensor body designed for mounting on evaporator coil assemblies
• Operates within a 2 degrees C close and 13 degrees C open temperature range

Compatibility

Designed as an OEM-style replacement defrost thermostat for commercial refrigeration unit coolers and evaporator assemblies requiring a 3-wire defrost thermostat with the stated temperature ratings.

Installation Notes

Installation should be performed by a qualified refrigeration or HVAC-R technician. Disconnect and lock out power to the refrigeration system before removing or installing the thermostat. The sensor body should be secured firmly against the evaporator coil surface per the original equipment mounting location. Verify wiring connections match the existing 3-wire defrost circuit before restoring power.

Technical Specifications

• Lead Configuration: 3-Wire
• Lead Length: 17 inches
• Sensor Body Length: 2 inches
• Closing Temperature: 35 degrees F (2 degrees C)
• Opening Temperature: 55 degrees F (13 degrees C)
• Body Material: Stainless Steel
• Housing Material: Plastic
• Color: Black / Silver

Standard Information

• Brand: BOHN
• Manufacturer Part Number: 5709l