Exam 31: Gas Heat

A condensing gas furnace uses ____ from a condensing type heat exchanger to increase the furnace efficiency.

On a gas furnace, what energizes the blower motor in the heat mode?

Three products of complete combustion of natural and LP gas are carbon dioxide, water vapor, and _________________________.

Another name for a downflow heating unit is ____________________.

A furnace with a vertical air flow through the heat exchanger and the blower compartment beneath the heat exchanger is called a(n) ____.

Butterfly shutters and sliding sleeves are examples of _________________________ and are used on atmospheric type gas burners.

In a conventional gas furnace, the hot flue gases are ____.

While the furnace is operating, heated air and flue products spill out of the burner compartment. What is the problem?

What is the difference between a yellow gas flame and an orange gas flame?

Liquified petroleum (LP) is heavier than air and can cause suffocation if not handled properly.

Primary air adjusters on atmospheric type gas burners are usually ____.

The flame in a gas fired furnace is burning with heavy yellow tips. What is the problem?

A gas furnace designed for use with natural gas can be used with liquified petroleum (LP) with no system modifications.

Spark ignition is important for roof top or package units located outdoors because of ____________________ problems.

If flue gases are not vented properly, carbon monoxide poisoning could result.

When a gas furnace ignites and is under "full-fire," why does the fan not come on immediately?

When the burners ignite, the burner flame is normal until the blower starts. At this time, continuous roll out occurs. What is the problem?

Why do propane and butane gas furnaces require 100% shut off in the event of pilot outage?

The gas flame will lift off the burner and be noisy if it receives too much primary air.