[ILM] 104D

Question 1

the actual operating range may be smaller or narrower than the control range

T or F

Answer 1

True

Question 2

low ambient limit is a low-cost control

Answer 2

True

Question 3

change-over & enthalpy controller changes mechanical cooling to free cooling

Answer 3

True

set at a dry bulb temp setpoint that is usually 50-60F

Question 4

mixed-air thermostat

Answer 4

is a proportional temp controllers that control the damper actuators of an economizer

Question 5

high limit =

Answer 5

high event = diffrential

usually have a non-adjustable setpoint that is 180 - 220F

Question 6

Roll-out limit thermostat comes in

Answer 6

when the main burner flame and flue gases remain in the burner compartment, instead of the heat exchanger

Question 7

split limit thermostat comes in

Answer 7

if the appliance has a backdraft problem

Question 8

air proving switch

Answer 8

is a safety device

prevents freezing

Question 9

unloading a compressor saves it from frequent cycling(short cycling)

Answer 9

True

Question 10

PLC

Answer 10

Programmable Login Controller