The disconnect should be sized at 115 of the minimum

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The disconnect should be sized at 115% of the minimum circuit ampacity 1.15 x 31.5 = 36.225 since disconnect sizes jump from 30 amps to 60 amps, a 60 amp disconnect will be needed.
89-11) Use the information on the data plate in Figure 89-24 to determine the maximum circuit breaker size for the unit.
89-12) What type of overcurrent protection is used with air conditioning equipment?
89-13) How should ductwork be sealed against air leaks?
89-14) How can vibrations and sound transmission from the unit to the ductwork be minimized?
89-15) Use Figures 89-27 and Table 89-2 to determine the correct amount of additional charge for a new split system with a 40 foot line set and a 3/8" liquid line. The factory charge includes enough refrigerant for 15 feet of line.
89-16) What position are the unit installation valves in when the unit is shipped?
89-17) When installing a split system, what should be done prior to opening the
270 installation valves? Evacuate the lines and coil
UNIT 90 REVIEW QUESTIONS ANSWER KEY 90-1) List the four phases of a planned maintenance service call.
90-2) What is the purpose of checking the supply voltage both before and after operating the system?
90-3) Name key safety aspects of combustion appliances that should be checked on a planned maintenance service call.
90-4) List operational checks to make during an air conditioning planned maintenance service call.
90-5) Why should caution be exercised when replacing a low efficiency air filter with a higher efficiency air filter?
90-6) How can performing planned maintenance save the customer money?
271 90-7) How does planned maintenance improve system reliability?

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