035-14520-001 Rev. B (0803)
Unitary Products Group
7
• If the suction line is 3/4" diameter - position the bulb
near the top of the copper tube as shown. If the tube is
7/8" diameter - position the bulb near the bottom of the
tube. Refer to Figure 8.
• Wrap the clamp, bulb & line securely with insulation
provided.
Orifice Metering Device
All non-TXV coils will have an orifice installed in the fitting
between the liquid line connection and distributor. See Figure
9. The factory installed orifice is identified on the unit data
plate. Also it is listed in Table 1.
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 of the indoor and outdoor sections, and/or long
total line lengths. An additional orifice is shipped with the out-
door unit in the literature packet for most requirements. Other
sizes must be ordered from the parts department if required.
Orifice Installation
A standard orifice is pre-installed in the unit and is marked on
the unit data plate. Refer to the outdoor unit instruction and
application data to determine the proper orifice required for
your particular system combination and piping conditions.
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,
change the orifice in the coil with the following procedure:
1.
Remove the liquid line fitting using 3/4" wrenches, and
remove the pre-installed orifice with a small diameter
wire or paper clip.
2.
Remove the new orifice from the packet and verify that it
is the correct number required. Install this orifice with the
rounded end toward the coil and the flat end outward per
Figure 9.
3.
Thread the liquid line fitting back in place on the coil.
Tighten the fitting hand tight and turn an additional 1/8
turn to seal.
NOTE:
This procedure should be done within 2 minutes to
keep air and contaminates from entering the coil. If the orifice
cannot be replaced and the coil resealed within 2 minutes,
then it should be temporarily closed to air using masking tape
(short term delay) or plugging/ capping (long term delay).
There is no need to purge the coil if this procedure is done
within the time limit.
4.
Mark the data plate with the orifice installed.
REFRIGERANT LINE CONNECTION
NOTE:
Confirm the orifice size before connecting lines.
See the outdoor unit installation instructions for the procedure
to install field supplied tubing for systems with sweat fittings.
Stub adapters are available to adapt sweat connections to
quick connections.
Connect lines as follows:
NOTE:
Route the refrigerant lines to the coil in a manner that
will not obstruct service access to the coil, air handling sys-
tem or filter.
FIGURE 8 :
Bulb Location
FIGURE 9 :
Orifice Installation
FOR 7/8” O.D. OR LARGER
FOR 3/4” O.D. OR SMALLER
-45º
45º
NOTE:
TXV BULB MUST BE INSULATED
ROTATE BULB TO
KEEP TAIL AT BOTTOM
*
*
BULB
BULB
PIPE
LIQUID LINE
SWIVEL COUPLING
(See Caution Below)
ORIFICE
DISTRIBUTOR
Coil is under 30 PSIG inert gas pressure. Relieve
pressure from schrader valve on liquid line side.
This fitting is a right-hand thread, turn counter-clock-
wise to remove.
Use 3/4" wrenches to turn fittings. Using pliers will
cause internal damage to the fitting.
