G2 Gas Technician Module 12 Exam Questions and answers with 100% Complete Solutions | verified &updated 2024

G2 Gas Technician Module 12 Exam Questions and answers with 100% Complete Solutions | verified &updated 2024 What does an Aquastat do? - Its an automatic operating switch (normally open). Sense water temperature of a boiler and closes when temperature drops. What does a low water cut off do? - Automatic safety control (normally closed). Senses water level in the boiler. If level drops the switch opens and shuts off the gas valve. in series with gas valve.,What does a water flow switch do? - Automatic safety control (normally open). Senses water flow and switch closes What does a Pressure Control Switch (pressuretrol) do in a steam boiler? - Automatic control that senses high and low steam pressure in a boiler. It closes to start burner on low pressure and opens at high temperature to stop the burner. Controls steam pressure in the boiler. What does a high pressure control do in a steam boiler and at what psi does it open? - Automatic safety control that is normally closed. It senses high pressure in the steam boiler and opens the switch. This is at 15 psi when it opens. How does a Thermocouple work? - Two dissimilar metals that are joined at two junctions. Heating one of the junctions produces a DC voltage. The temp difference between the hot and cold metals determines the quantity of the DC voltage.