How does venting compare on 80 percent and 90 percent efficient heating units?
A) 90 percent furnace vents are 10 percent larger in size than 80 percent furnace vents.
B) 80 percent furnaces use type B vent and 90 percent furnaces use PVC pipe for venting material.
C) 80 percent units require outside air to be piped in for combustion and 90 percent do not.
D) 80 percent furnaces use PVC vent and 90 percent furnaces use type B gas vent.
B
You might also like to view...
Do not run an engine generator set without a load for more than _____.
a. 5 minutes b. 10 minutes c. 15 minutes d. 1 hour
Which of the following conduit bodies has a single cover opening on both sides?
a. Type LB b. Type LL c. Type LR d. Type LRL
Choose the appropriate definitions for the sentences described below:
1) Null type device; 2) Amplifier; 3) Drift; 4) Transducer; 5) Precision; 6) Accuracy; 7) Calibration; 8) Resolution; 9) Linearity; 10) Backlash; 11) Relative Error; 12) Noise ( ) Device whose output is an enlarged reproduction of the essential features of the input wave and which draws power from a source other than the input signal ( ) Measure and generates an opposing effect to maintain zero deflection ( ) A device that converts input energy into a form of an output with different form of energy ( ) Ratio of difference between measured value and true value of the measurand ( ) Smallest increment in measurand that can be detected with certainty by the instrument ( ) Ability of the instrument to give identical output measurements when repeat measurements are made with the same input signal ( ) Gradual departure of the instrument output from the calibrated value ( ) Maximum distance or an angle, any part of the mechanical system can be moved in one direction without causing the motion of the next part ( ) Characteristic of the instrument whose output is a liner function of the input What will be an ideal response?
The air leaving an evaporator has a dry-bulb temperature of 85 °F and a wet-bulb temperature of 65°F. The air entering the evaporator has a dry-bulb temperature of 95°F and a wet-bulb temperature of 75°F. How many grains of moisture per pound of dry air were removed by the evaporator?
What will be an ideal response?