Heating

Question 1

What is secondary air?

Answer 1

Air added at the flame

Question 2

What are two optional information that could be seen on rating nameplates?

Answer 2

Orifice size and Output

Question 3

What is considered high altitude for a furnace?

Answer 3

2000 to 4500 ft

Question 4

How much percentage do you de-rate an altitude at sea level for a high altitude application?

Answer 4

10%

Question 5

Extra high altitude (above 4500 ft) needs to be de-rated what percent per how many ft

Answer 5

4% for every additional 1,000ft

Question 6

What is flashback?

Answer 6

Low manifold pressure causing slow gas/air mixture

Question 7

What is flame lift-off?

Answer 7

Manifold pressure too high causing over fire because high velocity gas/air mixture.

Question 8

What are the two types of burners?

Answer 8

Power burners and atmospheric burners

Question 9

What is the difference between a power burner and an atmosoheric burner?

Answer 9

Power burners use motors to supply combustion air. Atmospheric burners use the Venturi effect.

Question 10

Three different types of pilot burners?

Answer 10

Non-aerated, aerated, post aerated

Question 11

What is the difference between aerated and non-aerated flames?

Answer 11

Non-aerated flames do not use primary air. only secondy air for combustion.
Aerated Flames use secondary air giving 2 distinct cones.

Question 12

What type of primary/secondary air balance is found in a Aerated, oxidizing flame?

Answer 12

Large amount of primary, little secondary.

Question 13

What type of primary/secondary air balance is found in a Aerated, Neutral Flame?

Answer 13

Medium primary and secondary air

Question 14

What type of primary/secondary air balance is found in a Aerated, Carburizing Flame?

Answer 14

Small primary, a lot of secondary. large inner cone.

Question 15

What does an appliances input rating represent?

Answer 15

Amount of gas the appliance can safely handle

Question 16

What does an appliance output rating represent?

Answer 16

The difference between what it consumes and what is being supplied to the appliance

Question 17

What are four types of pilots?

Answer 17

1. Continuous
   2.Expanding
   3.Intermittent
   4.Interrupted

Question 18

True or False a continuous flame turns off

Answer 18

False, its always on

Question 19

Explain Expanding Pilot

Answer 19

Holds as a small flame then gets larger on a heating call

Question 20

Explain Intermittent Pilot

Answer 20

On call and throughout ignition

Question 21

Explain Interrupted pilot

Answer 21

On call and off after ignition

Question 22

Post Aerated burners collect primary air at which point?

Answer 22

At the combustion point. Also called “Incinerating” burners because of this. Burns lint dust etc.

Question 23

What is non-100% shut-off safety control

Answer 23

The main burner loses gas supply in a pilot outage but the pilot gas is not. Prohibited with LP gas

Question 24

100% Safe Hook-up does what on a pilot outage?

Answer 24

Turns off gas suply to main burner and the pilot gas.

Question 25

A thermopile is a bunch of thermocouples ties in series or in parallel?

Answer 25

In series

Question 26

The lead of a thermocouple should not be bent closer than… from the junctions

Answer 26

1”

Question 27

Pilot flame should evnvelope which portion of the thermocouple/pile?

Answer 27

Top 3/8” to 1/2”

Question 28

What is a proved pilot?

Answer 28

A pilot flame that is supervised by a flame failure device (Thermocouple)