8
SYSTEM START-UP
NOTES:
■
Units with crankcase heaters should have the high-voltage
power energized for 24 hours prior to start-up. Heat pumps
are equipped with a time/temperature defrost control with
field-selectable defrost intervals of 30, 60 or 90 minutes. This
setting should be adjusted at this time, if needed. The defrost
control also has SmartShift
TM
technology, which delays
compressor operation at the defrost initiation and
termination. If disabling this function is desired, move the
jumper from “DLY” to “NORM” on the defrost control.
■
Adequate refrigerant charge for a matching evaporator and
15 ft (4.6 m) lineset is supplied with the condensing unit. If
line set exceeds 15 ft (4.6 m) in length, refrigerant should be
added at 0.6 oz per foot of liquid line.
IMPORTANT: Open the suction service valve first. If the liquid
service valve is opened first, oil from the compressor may be
drawn into the indoor coil TXV, restricting refrigerant flow and
affecting operation of the system.
When opening valves with retainers, open each valve only until
the top of the stem is
¹⁄₈
" (3.2 mm) from the retainer.
NOTE: To avoid loss of refrigerant, do not apply pressure to the
retainer.
When opening valves without a retainer, remove the service valve
cap, and insert a hex wrench into the valve stem. Back out the
stem by turning the hex wrench counterclockwise. Open the
valve until it contacts the rolled lip of the valve body.
NOTE: These are not back-seating valves. It is not necessary to
force the stem tightly against the rolled lip.
After the refrigerant charge has bled into the system, open the
liquid service valve. The service valve cap is the secondary seal
for the valves and must be properly tightened to prevent leaks.
Make sure the cap is clean and apply refrigerant oil to the threads
and sealing surface on the inside of the cap. Tighten the cap
finger tight, and then tighten an additional
¹⁄₆
of a turn (1 wrench
flat), or to the following specification, to properly seat the sealing
surfaces.
NOTE: Do not introduce liquid refrigerant from the cylinder into
the crankcase of the compressor as this may damage the
compressor.
1. Break the vacuum by fully opening liquid and suction base
valves.
2. Set thermostat to call for cooling.
3. Check indoor and outdoor fan operation and allow system to
stabilize for 10 minutes for fixed orifices and 20 minutes for
expansion valves.
FINAL CHARGE ADJUSTMENT
NOTE: The outdoor temperature must be 60°F (16ºC) or higher.
Set the room thermostat to COOL, the fan switch to AUTO and
set the temperature control well below room temperature.
1. Purge the gauge lines.
2. Connect the service gauge manifold to the base valve service
ports.
3. Run the system (on low stage for 2-stage units) for
10 minutes to allow the pressures to stabilize.
4. Check subcooling and/or superheat as detailed in the
following sections.
Superheat Formula = Suction Line Temperature - Saturated
Suction Temperature
Subcooling Formula = Saturated Liquid Temperature - Liquid
Line Temperature
Goodman 25
POSSIBLE REFRIGERANT LEAK
To avoid a possible refrigerant leak, open the service
valves until the top of the stem is
¹⁄₈
" (3.2 mm) from the
retainer.
CAUTION
■
³⁄₈
" valve to 5 to 10 in.-lbs
■
³⁄₄
" valve to 5 to 20 in.-lbs
■
⁵⁄₈
" valve to 5 to 20 in.-lbs
■
⁷⁄₈
" valve to 5 to 20 in.-lbs
Goodman 25
POSSIBLE REFRIGERANT LEAK
To avoid a possible refrigerant leak, open the service
valves until the top of the stem is
¹⁄₈
" (3.2 mm) from the
retainer.
CAUTION
Goodman 26
REFRIGERANT UNDER PRESSURE!
• Do not overcharge system with refrigerant.
• Do not operate unit in a vacuum or at negative
pressure.
Failure to follow proper procedures may cause
property damage, personal injury or death.
WARNING
Goodman 27
Use refrigerant certified to AHRI standards. Used
refrigerant may cause compressor damage, and will void
the warranty. Most portable machines cannot clean used
refrigerant to meet AHRI standards.
CAUTION
Goodman 28
Violation of EPA regulations may result in fines or other
penalties.
NOTICE
Goodman 29
Operating the compressor with the suction valve closed
will void the warranty and cause serious compressor
damage.
CAUTION
