035-17421-000 Rev B (700)
Unitary Products Group
7
ORIFICE SELECTION
YORKMATE FLOW CONTROL COILS
NOTE: The proper orifice must be installed in the indoor coil liq-
uid connection prior to the connection of the refrigerant
lines.
Sweat coils are shipped with a standard orifice in a plastic
bag attached to the liquid line connection or factory installed
in the liquid line distributor. The standard orifice size is
marked on the coil data plate.
The orifice that is shipped with the coil is based on the “most
sold” combination, but it may have to be changed, depending
on the capacity and efficiency of the outdoor unit, elevation
differences, and/or long total line lengths. An additional ori-
fice(s) is shipped with most outdoor units in the literature
packet for the most commonly required replacement combi-
nations. Other sizes must be ordered from the Parts Depart-
ment if required.
See the appropriate Tabular Data Sheet for the correct orifice
size. If the orifice sizes match, nothing further is required and
the refrigerant lines may be connected per the outdoor unit
instruction. However, if another orifice should be used, see
the coil instruction for details to change the orifice in the coil.
ELECTRICAL CONNECTIONS
GENERAL INFORMATION & GROUNDING
Check the electrical supply to be sure that it meets the values
specified on the unit nameplate and wiring label.
Power wiring, control (low voltage) wiring, disconnect
switches and over current protection to be supplied by the
installer. Wire size should be sized per NEC requirements.
The complete connection diagram and schematic wiring label
is located on the inside surface of the unit electrical box cover
and this instruction.
POWER WIRING
1.
Install the proper size weatherproof disconnect switch
outdoors and within sight of the unit.
2.
Run power wiring from the disconnect switch to the unit.
3.
Remove the control box cover to gain access to the unit
wiring. Route wires from disconnect through power wir-
ing opening provided and into the unit control box as
shown in Figure 6.
4.
Install the proper size time-delay fuses or circuit breaker,
and make the power supply connections.
5.
Energize the crankcase heater to save time by preheat-
ing the compressor oil while the remaining installation is
completed.
ACCESSORY WIRING
The electrical accessories available for this unit are a two
stage cooling thermostat and an optional De-humidification
Control. Refer to the individual instructions packaged with the
accessories for installation.
THERMOSTAT MOUNTING / WIRING
This condensing unit must be installed with the factory rec-
ommended thermostat, or any conventional heat pump ther-
mostat.
The thermostat should be located about 5 ft. above the floor,
where it will be exposed to normal room air circulation. Do not
place it on an outside wall or where it is exposed to the radi-
ant effect from exposed glass or appliances, drafts from out-
side doors or supply air grilles.
Sweat coil is under 35 PSIG helium pressure.
All field wiring must USE COPPER CONDUCTORS
ONLY and be in accordance with Local, National Fire,
Safety & Electrical Codes. This unit must be grounded
with a separate ground wire in accordance with the
above codes.
FIGURE 6 : TYPICAL FIELD WIRING
POWER
WIRING
CONTROL
WIRING
All outdoor wiring
must be weather-
proof. Use copper
conductors only.
GROUND
LUG
LOW VOLTAGE
JUNCTION BOX
