Rheem 018J*Z, Installation Instructions Manual

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19
HARD START COMPONENTS
Start components are not usually required with the scroll compressors used in
(-)ANL/(-)APL/(-)APM condensing units, but are available for special cases and
where start components are desirable to reduce light dimming.
TIME DELAY CONTROL (TDC)
The time delay (TDC) is in the low voltage control circuit. When the compressor shuts
off due to a power failure or thermostat operation, this control keeps it off at least 5
minutes which allows the system pressure to equalize, thus not damaging
the compressor or blowing fuses on start-up.
LOW AMBIENT CONTROL (LAC)
This component senses compressor head pressure and shuts the condenser fan off
when the head pressure drops below designated levels. This allows the unit to build
a sufficient head pressure at lower ambient in order to maintain system balance and
obtain improved capacity. Low ambient control should be used on all equipment oper-
ated below 65°F ambient.
OUTDOOR UNIT COVERS
Outdoor condensing unit covers are available if the homeowner requests a cover for
their unit. With the complete model number for the unit, the correct cover can be
obtained through an authorized distributor.
SERVICE
SINGLE-POLE COMPRESSOR CONTACTOR (CC)
Single-pole contactors are used on all standard single phase units up through 5
tons. Caution must be exercised when servicing as only one leg of the power sup-
ply is broken with the contactor. Two pole contactors are used on some three
phase units.
!
CAUTION
FAILURE TO REMOVE CONDENSING UNIT COVER BEFORE OPERATING
OUTDOOR UNIT CAN CAUSE COMPONENTS TO FAIL.