Manual 2100-738C
Page
35 of 73
Pressure Service Ports
High and low pressure service ports are installed on
all units so that the system operating pressures can be
observed. Pressure charts are located on the backside
of the units lower service door, as well as in Table 5 on
page 38. It is imperative to match the correct pressure
chart to the unit by model number. All upper service
doors must be attached to obtain proper reading. The
service ports are in the lower compressor section on the
tubing adjacent to the compressor.
This unit employs high-flow Coremax valves instead of
the typical Shrader-type valves.
WARNING! Do NOT use a Schrader valve core removal
tool with these valves. Use of such a tool could result
in eye injuries or refrigerant burns!
To change a Coremax valve without first removing the
refrigerant, a special tool is required which can be
obtained at www.fastestinc.com/en/SCCA07H. See the
replacement parts manual for replacement core part
numbers.
Piping Access to Unit
Water piping to and from the coaxial water coil is
intended to enter/exit the unit through the rectangular
hole. See Figures 1 (page 8), 8A (page 14), 27 (page
36) and 28 (page 37). The connections on the water
coil are a double O-ring with a retainer nut that secures
it in place.
Various double O-ring fittings are available to make
it possible to connect to the coaxial coil with various
methods and materials. The methods include 1" barbed
fittings (straight and 90°), 1" MPT (straight and 90°),
and 1¼" hot fusion fitting with P/T fitting). (See Table
6 on page 39.)
NOTE
All double O-ring fittings require “hand
tightening only”. Do not use a wrench or pliers
as retainer nut can be damaged with excessive
force. Avoid cross-threading the nut.
NOTE
Apply petroleum jelly to O-rings to prevent
damage and aid in insertion.
System Start Up
Step 1 – Close disconnect switch(es) and set the
thermostat to cool and temperature to the
highest setting.
Step 2 – Check for proper airflow across the indoor
coil.
Step 3 – Connect the service gauges and allow the
unit to run for at least 10 minutes or until
pressures are stable. Check pressures to the
system pressure table attached to the unit
service panel.
Step 4 – Fill out Ground Source Heat Pump
Performance Report.
