*EMS* HVAC contractor licensing practice test

The below questions are similar to those asked when attempting to get your *HVAC contractors* *or Masters* license. This practice test is *not intended* for those seeking a certification in* service*, such as NATE. Our practice test is absolutely FREE. You may take the test as many times as you wish. If you wish to save time, the answers, and where we got them, are available HERE for a measely 40 bucks.

ANSWER **B.**

One of the most useful equations in the hvac industry is: **BTU = CFM X 1.1 X TD. **This equation can be flipped arround to **CFM = BTU/1.1 X TD** or **TD = BTU/1.1 X CFM. **TD may be temperature difference or temperature rise (TR). You will likely need a variation of this equation to answer some exam questions.

To solve the above problem use the equation CFM = BTU/1.1 x TD

Where BTU is the output of the furnace. The furnace is rated 75,000 btuh. However, since it is 85% efficient, the net output is 75,000 X .80 = **60,000 btuh** output.

Now apply the equation, CFM = BTUH/ 1.1 x td

**CFM** = 60,000/1.1 X 45 **= 1212 CFM**