Installation guide

REFRIGERATION SYSTEM
A. COMPONENT MATCHES
Check to see that the proper system componenis are in
place, especially the indoor coil.
R-410A outdoor units can only be used with R-410A
specific indoor coils. If there is a refrigerant mis—maitch,
consult the indoor coil manufacturer to determine if a
refrigerant conversion kit is available for the indoor coil.
This outdoor unit is designed to achieve maximum
efficiency when used with indoor coils that utilize a TXV
refrigerant metering device or Piston with Teflon ring
metering device. If any other type of metering device is
installed on the indoor coil, consult the indoor coil
manufacturer to determine if a conversion kit is available.
Installing with TXV.
When installing a TXV on an indoor coil, follow the
instructions provided with the new TXV.
A typical TXV installation is shown in Figure 3.
Figure 3 Typical TXV Installation
INDOOR
COIL
EQUALIZER \.|
TUBE
SENSING | SUCTION
BULB TUBE
~~ LIQUID
TUBE
TXV
10 O'Clock
2 O'Clock
__ k SENSING BULB
Lf ccomon TUBE
7/8 IN. OD & SMALLER
Installing with Indoor Piston - cooling operation.
(Heat pumps also use an outdoor piston for heating
operation, refer to section F.)
Check piston size shipped with indoor unit to see if it
matches required indoor piston size shown on outdoor
unit rating plate.
If it does not match, replace indoor piston with cooling
piston, according to size marked on outdoor unit rating
plate. (Some outdoor models include a cooling piston in
the accessory bag.)
Heating piston is shipped in the service valve - refer to
section F.
Example fan coils with piston: FEM4P, FSM4P, FSU4P.
See Figure 4.
When changing indoor piston, use a back-up wrench.
Hand tighten hex nut, then tighten with wrench 1/2 turn.
Do not exceed 30 ft-lbs.The indoor piston contains a
Teflon ring (or seal) which is used to seat against the
inside of distributor body, and must be installed properly
to ensure proper seating in the direction for cooling
operation.
Figure 4 Indoor (cooling) Piston
BRASS DISTRIBUTOR
HEX NUT TEFLON SEAL
TEFLON RING
PISTON
sommes
FLOW IN
COOLING
BRASS
PISTON
RETAINER HEX BODY
aa STRAINER
CI
CAUTION
PRODUCT OPERATION HAZARD
Failure to follow this caution may result in improper product
operation.
If using a TXV in conjunction with a single-phase reciprocat-
ing compressor, a compressor start capacitor and relay are
required. Consult outdoor unit pre-sale literature for start as-
sist kit part number.
428 01 5103 02