Duct systems should be installed according to ____ Standards
SMACNA
The type of flue pipe used on gas 80% standard furnace venting systems serving
... [Show More] gas fired systems
Type B-Vent
Which type of gauge would you use for very high vacuums?
McLeod type gauge
How many BTUs are equal to one kilowatt hour
3,414 BTU
When adjusting gas fired furnaces above 2000 feet, the BTU per hour input should be reduced 4% for each _____ feet above sea level.
4% for every 1,000 feet
How are residential furnace blower motors classified
by starting method
What is the equation for determining heat loss through a material
Q = U times A times TD
What is the overfire rating on a small draft hood
0.02 inches
what is the equation for determining minimum size air supply for a blower type furnace
2 divided by 1000 times the BTU of the furnace
what is the equation for determining minimum size air supply for a gravity type furnace
7 divided by 1000 times the BTU of the gravity furnace
the type of bub that measures evaporative cooling
wet bulb
the heating value of natural gas is
1100 BTU per cubic foot
Silver solder starts to flow at or above
1150 degrees fahrenheit
how high must a 12"diameter flue pipe project above a pitched roof line
2 feet
Ducts conveying flammable dusts must have a clearance from combustible materials of not less than how many inches
18 inches
A furnace installed in an attic must have a minimum access opening of
22 by 30 inches
The Cal Osha exposure limit for asbestos is ____ f cc
0.1 f cc
If the asbestos content of a material encountered at a work site exceeds 1%, what should you do?
put up a caution sign and close off the affected area
On a residential system that uses more than 50 pounds of freon, what is the maximum annual leakage rate allowed before repairing the leak is mandatory. What is it for commercial?
15%, 35%
what is the minimum safe landing clearance diameter for a helicopter?
200 feet
what is the max flexible connector you can use for a heating furnace
3 feet
what is the boiling point of R22 at atmospheric pressure?
negative 41 degrees
what is the minimum clearance between an air duct an a rafter
1 inch
why should there be clearance between an air duct and a rafter?
fire safety purposes [Show Less]