Gas safety and controls

Multiple Choice

Which of the following is NOT listed as a control and safety device?

• Valves

• Thermostats

• Transformers

• Regulators

Open Ended

Explain how a bimetallic strip works and describe one practical application for it.

Multiple Select

Which of the following statements about thermoelectric devices is/are correct?

• They generate electric current when two dissimilar metals are joined and heated.

• They are used to hold open gas control valves.

• A thermopile produces a higher voltage than a thermocouple.

• They are used to measure atmospheric pressure.

Fill in the Blanks

A regulator reduces incoming pressure (supply pressure) to

pressure (working pressure).

Open Ended

Describe the role of a diaphragm and atmospheric pressure in the operation of a regulator.

Fill in the Blanks

When used for controlling gas, solenoids must be

to open and also fast acting.

Multiple Choice

Which of the following components is commonly used for over temperature protection in electronic circuits?

• Thermistors

• Pressure switches

• Mercury switches

• Bimetal thermostats

Open Ended

Explain how tip switches and mercury switches contribute to tip over protection in safety systems.

Fill in the Blanks

A diaphragm in a pressure switch moves in response to changes in

.

Multiple Select

Which of the following statements about the oxygen depletion system is/are correct?

• It prevents CO poisoning by shutting down the appliance when oxygen is low.

• It increases the gas flow when oxygen is low.

• The thermocouple cools and releases the gas control valve when oxygen drops.

• The pilot flame lifts off in search of oxygen when primary air is low.

Open Ended

Describe the process of flame rectification and its importance in gas control systems.

Fill in the Blanks

The main purpose of a thermostat is to maintain a specific

within an environment.

Multiple Choice

Which of the following is NOT a type of ignition device?

• Pilot flame

• Filament

• Thermistor

• Flash tube

Open Ended

How does a Peizo igniter produce a spark?

Multiple Choice

What is the main purpose of a regulator in a combination control valve system?

• To ignite the burner

• To control gas pressure

• To detect flame failure

• To cut off energy supply

Multiple Select

Which functions can be controlled by a combination control valve?

• Gas valve

• Thermostat

• Energy Cut Off (ECO)

• Ignition coil

Fill in the Blanks

A device that changes its resistance with temperature is called a

.

Open Ended

What are some important safety considerations when working with gas control devices?

Multiple Choice

Why is it important to have gas control and safety devices in gas systems?

• To ensure safe operation and prevent accidents

• To increase the speed of gas flow

• To reduce the cost of gas

• To make the system look more complex

Open Ended

Describe a situation where a gas safety device could prevent a serious accident. What role does the device play in ensuring safety?