Phase4Mod11devices

Which of the following flame supervision devices senses the presence of the flame not the presence of heat?

• Thermo-electric.

• Bi-metallic.

• Liquid expansion.

• Rectification.

A vitiation sensing device works on the principle of:

• A flame cooling in a vitiated atmosphere.

• A flame lifting in a vitiated atmosphere.

• A flame lighting in a vitiated atmosphere.

• A flame extinguishing in a vitiated atmosphere.

The flame supervision device fitted to a gas fire must close upon flame failure within a minimum time period of:

• 1 minute

• 2 minute

• 3 minute

• 4 minute

What type of lubricant should be used when serving gas taps?

• Molybdenum desulphated grease

• High temperature silicone grease.

• Carb-hydroxy grease.

• Low-modulus fungicidal silicone grease.

Which of the following flame supervision devices is generally the slowest acting?

• Thermo-electric.

• Bi-metallic.

• liquid expansion.

• Rectification.

What is the likely fault if a cooker oven burner extinguished after a period of approximately 15 minutes?

• Faulty flame supervision device.

• Blocked oven injectors.

• Blocked oven thermostat by-Pass.

• Under gassing causing incomplete combustion.

To assess the effectiveness of a thermo-electric FSD, the operative should extinguish the flame:

• And listen for the click of the valve.

• And listen for the click of the valve and verify the valve has closed using a pressure gauge.

• And wait for the appliance governor to lock up.

• And calculate the gas rate.

A solenoid is used to actuate the gas flow by using.

• A low pressure supply.

• An electric current.

• A thermo electric FSD.

• A high pressure supply.

Which is the most common type of flame supervision device is fitted to domestic cooker ovens?

• Thermo-electric.

• Bi-metallic.

• Liquid expansion.

• Rectification.

A thermocouple will produce an electro-motive force when the tip is in a flame. If in good condition , the range for common thermocouples is/

• 5-15mV.

• 10-20mV.

• 15-30mV.

• 20-40mV.