Heating

Question 1

If an appliance is installed above 4500 feet, what percentage is the appliance de-rated?

Answer 1

4 % for each additional 1000 feet above the high altitude rating

Question 2

What is the maximum input rating?

Answer 2

The amount of gas that the appliance can safely handle

Question 3

What is the output rating?

Answer 3

The difference between what it consumes and what is made available to the medium being heated

Question 4

What’s Manifold Pressure?

Answer 4

Controls fuel supply and creates the means to entrain primary air to the main burner

Question 5

What will happen if the manifold gas pressure is too high?

Answer 5

The appliance will over fire and the velocity of the gas/air mixture speed will increase and cause Flame lift-off

Question 6

What will happen if the manifold gas pressure is too low?

Answer 6

The appliance will be under fired and the gas/air mixture speed will be too slow causing Flashback

Question 7

What’s the difference between a power burner and an atmospheric burner?

Answer 7

-Power burners use a mechanical device, usually a blower installed on the inlet side of the burner (upstream) controls all the air entering the burner

• atmospheric burners uses a difference in atmospheric pressure to entrains air into the gas stream

Question 8

What is the orifice on a burner? And what are the effects if the orifice is too large or too small?

Answer 8

• Determines volume of gas passing to the burner
• if the orifice is too large the burner will be over gassed and incomplete combustion will result
• If orifice is too small, the burner will operate satisfactory but will not realize it’s full capacity