Fixed 40° F Temperature Thermostat

The 42001-NEL thermostat is ideal for applications where freeze protection or lowerrange temperature control is critical. In cold climates the thermostat switches heating devices that prevent pipes, valves, tanks and fittings from freezing.

This thermostat can be used in ambient-sensing applications by placing the sensor in the air or as a line-sensing thermostat by securing the bulb to the pipe or tank. It can be used as a single circuit control or as a pilot control for several circuits by switching a contact. Set point at factory is 40 degrees F (5C).

Enclosure Rating NEMA 4X
Entries One ¾ inch NPT conduit hub
Set Point 40 °F (5 °C) Close on decreasing temperature
Sensor exposure limits -30 to 140 °F (-35 to 60 °C)
Housing exposure limit -30 to 140 °F (-35 to 60 °C)
Enclosure material Polycarbonate black
Switch SPD, prewired snap action
Electrical rating 22 [email protected] 125/250/480 VAC
Accuracy ±1% of full scale
Sensor & capillary type Copper tin plated, Silicone oil filled bulb3.12” (79mm) .39” (10mm) diameter10’ (3.05m) long capillary
Connection 14 AWG stranded copper wire, PVC
Approvals CSA and UL Listed (Ordinary Areas)
Manufacturer Nelson


Ordering Information:


Thermostat, 40° Degrees

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