25
There are 2 relief valves for the oil separator (30HXA) or
condenser (30HXC); one for each circuit. Most local codes
require that these devices be piped to the outside. If vent piping
is required by local codes, these connections have been provid-
ed to aid in the connection of vent piping in accordance with
ASHRAE 15 (American Society of Heating, Refrigeration, and
Air Conditioning Engineers), Safety Code for Mechanical
Refrigeration. If vent piping is required, do not restrict the vent
flow in any way.
NOTE: When accessory suction service valve kit is installed,
there is one additional high-side pressure relief valve per
compressor. These are located on the discharge line between
the muffler and the discharge shut-off valve. Pipe these valves
per local codes.
Step 4 — Make Electrical Connections —
The elec-
trical characteristics of the available power supply must agree
with the unit nameplate rating. Supply voltage must be within
the limits shown.
FIELD POWER CONNECTIONS (See Fig. 18) — All power
wiring must comply with applicable local and national codes.
Install field-supplied, branch circuit fused disconnect(s) of a
type that can be locked off or open. Disconnect(s) must be
located within sight and readily accessible from the unit in
compliance with NEC Article 440-14. See Tables 6A and 6B
for unit electrical data. See Tables 7A and 7B for compressor
electrical data.
All units have a single location for power entry to simplify
the field power wiring. The maximum wire size that the unit
terminal block or non-fused disconnect will accept is 500 kcmil
(except units equipped with 250 amp non-fused disconnects
which will accept a maximum wire size of 300 kcmil).
All units require at least one field-supplied power supply.
Refer to Fig. 18 for a list of units that require 2 field-supplied
power supplies. Units that require 2 power supplies are listed
under TB1B in the Standard Power and Non-Fused Disconnect
Option sections of Fig. 18.
IMPORTANT: The 30HX units have a factory-installed
option available for a non-fused disconnect for unit power
supply. If the unit is equipped with this option, all field
power wiring should be made to the non-fused disconnect
since no terminal blocks are supplied.
COMPRESSOR A1
COMPRESSOR A2
CIRCUIT A
ECONOMIZER
TRANSDUCER
CIRCUIT A ECONOMIZER
CONNECTION
(1/4 IN. FLARE FITTING)
TO CIRCUIT A
ECONOMIZER
CONNECTION
CIRCUIT A
DISCHARGE
LINE
1/4 IN. EQUALIZER
LINE
CIRCUIT A
BACK
PRESSURE
VALVES
OIL
SEPARATOR
Fig. 19 — 30HXA Units Back Pressure Valve Equalizer Line Connection (076-186 Sizes Shown)
Fig. 20 — 30HXA206-271 Back Pressure Valve Equalizer Line Connection (Circuit A)