Company WCX Series Installation Manual

Then check the sub-cooling of the liquid refrigerant at the outdoor unit to insure a proper liquid seal is present at the expansion

valve. For optimum system performance at outdoor conditions between 80 to 95 degrees, the system should be charged to a sub-cool-

ing level of 11-13 degrees at the outdoor unit (pressure measurement to be taken at the service valve and temperature measurement to

be taken 6 inches downstream from the service valve). Superheat should be measured at the same distance from the suction service

valve and should be stable in the range of 15-20 degrees. In the event that superheat is unstable increase the system charge by one

ounce. Re-measure superheat and continue adding charge until superheat is stable. Do not exceed 18 degrees sub-cooling.

ELECTRICAL POWER SUPPLY

The electric installation must be in accordance with the National Electric Code and any local codes or ordinances. Use a separate

branch circuit for this unit and locate a disconnecting means within sight of the unit and readily accessible for service personnel.

Minimum circuit ampacity and maximum circuit breaker size information is shown on the unit nameplate. Use copper conductors

only. NOTE: A Compressor Time Delay Relay may be required and will need to be ﬁ eld installed if rapid cycling of the compressor

occurs.

WARNING: Disconnect all power to unit before servicing ﬁ eld wires or removing control package. The disconnect

(when used) does not disconnect power to the line side of the disconnect, but does allow safe service to all other parts

of the unit. If the unit does not have a disconnect, disregard the foregoing. Instead, make sure that a disconnecting

means is within sight from, and is readily accessible from, the unit. Disconnect all power to the unit before performing

any maintenance or service on it. Failure to follow this WARNING can cause electrical shock, ﬁ re, personal injury or

death.

CAUTION: Operation of unit on improper line voltage constitutes abuse and could affect unit reliability and opera-

tion. See unit rating plate. Do not install a system where voltage or phase imbalance may ﬂ uctuate above or below

permissible limits. If low voltage conditions exist, use of Start Assist Device may be required.

THERMOSTAT WIRING

Run a thermostat cable of at least 2 - wires between the condensing unit and the indoor unit. Pigtail leads are provided at the con-

densing unit. Make connections using wire nuts and tape for security. (See ﬁ gure 2)

SERVICE & MAINTENANCE

Keep the inside of the unit clean and be certain the drain holes in the base of the pan are open to assure rain drainage from the unit.

Keep the condenser coil clean. Any restriction of the condenser air ﬂ ow can seriously effect the system performance.

Maintenance Updates

For a current copy of the Maintenance Program log onto www.ﬁ rstco.com and look under “Product Information”.

FIGURE 2

THERMOSTAT WIRING

24VAC - CLASS 2

WALL

MOUNTED

THERMOSTAT

FAN COIL

UNIT

CONTACTOR

* IF HEATING IS REQUIRED