Carrier GEMINI SELECT 38APS025-065 Product Data page 105

2. Long line length check valves are required for
liquid line installation on all linear line length
applications of more than 100 ft (30.5 m) to
prevent liquid migration during unit shutdown.
For any 025-030 size dual circuit unit applica-
tion where evaporator is located higher than
the condensing unit, check valves are required
for linear line length above 55 ft (16.8 m).
3. Units shall include one factory-installed suction
line accumulator for each refrigerant circuit.
G. Controls and Safeties:
1. Unit ComfortLink™ controls shall include:
a. Optional scrolling marquee display.
b. Carrier Comfort Network
capability.
c. Unit control with standard pressure trans-
ducer, discharge pressure transducer and
suction temperature thermistors.
d. Current alarm list and alarm history list on
display.
e. Automatic compressor lead/lag control.
f. Service run test capability.
g. Compressor minimum run time (3 minutes)
and minimum off time (3 minutes).
h. Service diagnostic mode.
i. Self-contained low voltage control circuit.
j. Cycle condenser fans to maintain proper
head pressure control.
k. Capacity control with staging compressors.
l. Optional digital scrolls to stage compressors
and cycle digital compressor for maintaining
desired leaving air temperature set point.
m. Alarm relay output to indicate when unit is
in alarm condition.
2. Minimum unit safety devices shall include:
Solid-state compressor lockout to provide
optional reset capability at the space thermostat
if any of the following safety devices trip and
shut off compressor.
a. Compressor lockout protection for internal
or external overload.
b. Low pressure protection.
c. High pressure protection (high pressure
switch or internal).
d. Compressor reverse rotation protection.
e. Loss of charge protection.
f. Low suction superheat protection.
g. Short cycle protection.
h. Suction and discharge pressure transducers.
i. Circuit breakers or fuses for short circuit pro-
tection of compressors.
H. Operating Characteristics:
1. The capacity of the condensing unit shall meet
or exceed ____ Btuh (____kW) at a suction
®
(CCN) system
temperature of ____ F (____C). The power con-
sumption at full load shall not exceed ____Btuh
(____kW).
2. The combination of the condensing unit and
the evaporator or air handling unit shall have a
total net cooling capacity of ____ Btuh
(____kW) or greater at conditions of ____ cfm
(____L/s) entering-air temperature at the evap-
orator at ____F (____C) wet bulb and ____F
(____C) dry bulb, and air entering the condens-
ing unit at ____F (____C).
3. The system shall have an Energy Efficiency
Ratio (EER) of ____Btuh/watt or greater at
standard ARI conditions.
I. Electrical Requirements:
All unit power wiring shall enter unit cabinet at a sin-
gle location (115 and 130 size units available with
dual point power with terminal block).
J. Special Features:
1. Low Ambient Control:
a. Control shall regulate fan motor speed in
response to the saturated condensing tem-
perature of the unit. The control shall be
capable of operating with outdoor tempera-
–
tures at 20 F ( 28.9 C).
®
b. Motormaster
available as a factory-installed option or field-
installed accessory for all units.
2. Optional E-Coated MCHX Condenser Coil:
E-coated aluminum microchannel coils shall
have a flexible epoxy polymer coating uni-
formly applied to all coil external surface areas
without material bridging between fins or lou-
vers. Coating process shall ensure complete coil
encapsulation, including all exposed fin edges.
E-coat thickness of 0.8 to 1.2 mil with top coat
having a uniform dry film thickness from 1.0 to
2.0 mil on all external coil surface areas, includ-
ing fin edges, shall be provided. E-coated coils
shall have superior hardness characteristics of
2H per ASTM D3363-00 and cross-hatch
adhesion of 4B-5B per ASTM D3359-02.
E-coated products shall have superior impact
resistance with no cracking, chipping or peeling
per NSF/ANSI 51-2002 Method 10.2 (U.S.A.
Standards).
3. Sound Reduction:
a. Low sound fan for sound reduction is avail-
able as a factory-installed option or field-
installed accessory for all units.
b. Compressor sound blankets for additional
sound reduction are available as a factory-
installed option on all units having low sound
fans or as a field-installed accessory.
4. Digital Compressor Option:
Modification shall include digital compressor
to provide incremental
–
low ambient control shall be
steps for tighter
105