Chapter 129 Flashcards
Atmospheric air may be heated or cooled by installing ______ in the ductwork or in air handling units
coils
A finned-tube coil may have a heat transfer area from _________ time more than that of bare fare tubes
10-30
Two types of coils used almost exclusively for heating and cooling services are the:
spiral-finned tube, continuous-plate finned tube
Coil capacity ______ with the number of fins per unit length of the tube.
increases
The pressure drop across the coil will determine the:
size of the fan motor
The greater pressure drop across the coil:
the more powerful the fan motor will have to be
A characteristics of a double serpentine water coil is:
low water pressure drops
Which type of coil is designed to produce a high heat capacity with a limited water quantity?
half serpentine
How can the bond between the fins and tube in a heating coil be improved?
solder coating the tubes and fins
With counterflow arrangement of air and water the water supply connection is on the same side as the?
entering air
When the water velocity in the tubes is between 0.3 and 2.4 m/s which water coil is used?
single serpentine
To obtain full rated capacity of water coils what should be done?
connect the water supply for a counterflow arrangement
Average velocity of the air flowing over the face area of the fin surface is
face velocity
The fin surface area of a heating or cooling coil is called:
secondary surface area
Air venting, in an air conditioning system, is required for adequate:
water distribution in the coils and supply/return line
