A pressure switch that contains a high and a low switch is called a:

A pressure switch that contains a high and a low switch is called a:

• A. Thermostat
• B. Humidistat
• C. Time Clock
• D. Dual-Pressure Switch

Answer: (D)

The main idea is a switch designed to respond to two different pressure levels, providing protection and control at both ends of the pressure range. A dual-pressure switch has a high setpoint and a low setpoint, so it can shut the system off when pressure gets too high and restart it only after pressure falls to the low threshold. This dual threshold setup prevents both damage from overpressure and unsafe operation from underpressure, and it’s a common safeguard in compressors, refrigeration, and HVAC systems. In contrast, a thermostat controls temperature, a humidistat controls humidity, and a time clock follows a schedule—none of these involve monitoring two pressure levels.

The main idea is a switch designed to respond to two different pressure levels, providing protection and control at both ends of the pressure range. A dual-pressure switch has a high setpoint and a low setpoint, so it can shut the system off when pressure gets too high and restart it only after pressure falls to the low threshold. This dual threshold setup prevents both damage from overpressure and unsafe operation from underpressure, and it’s a common safeguard in compressors, refrigeration, and HVAC systems.

In contrast, a thermostat controls temperature, a humidistat controls humidity, and a time clock follows a schedule—none of these involve monitoring two pressure levels.