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3. Unit Controls:
Safety devices on all units shall include low-
pressure sensor or loss-of-charge switch, high-
pressure switch, low water temperature sensor,
and condensate overflow switch.
4. The standard Complete C electronic control
system shall interface with the unit mounted or
remote heat pump (Y,O) wall thermostat
(mechanical or electronic). The control system
shall have the following features:
a. 50 VA transformer.
b. Anti-short cycle time delay on compressor
operation; time delay shall be 5 minutes
minimum.
c. Random start on power-up.
d. Low voltage protection.
e. High voltage protection.
f. Condensate overflow shutdown.
g. Unit shutdown on low refrigerant pressures.
h. Unit shutdown on high or low water temper-
ature (selectable for antifreeze solutions).
i. Option to reset unit at thermostat or discon-
nect. Fault type shall be retained in memory
if reset at thermostat.
j. Automatic intelligent reset. Unit shall auto-
matically restart 5 minutes after shutdown if
the fault has cleared. Should a fault occur
3 times sequentially, then lockout will occur.
k. Ability to defeat time delays for servicing.
l. Light-emitting diode (LED) to indicate high
pressure, low pressure, improper voltage,
water coil freeze protection, air coil freeze
protection, condensate overflow, and con-
trol status.
m. Unit Performance Monitor to indicate ineffi-
cient operating conditions prior to unit
lockout.
n. Remote fault type indication at thermostat.
o. Single harness connection for all safety
devices.
p. Selectable 24-v or pilot duty dry contact
alarm output.
q. 24-v output to cycle a motorized water valve
with compressor contactor.
r. The control box components shall be
easily accessible with a swing out control
compartment.
s. Standard unit-mounted MCO (manual
changeover) thermostat operating controls
shall consist of temperature setting dial
knob, push button switches for Stop, Fan
only, Hi Cool, Lo Cool, Hi Heat, Lo Heat.
Unit-mounted thermostats shall have a
remote sensor for sensing the return-air
temperature.
5. The optional Deluxe D electronic control shall
have all the features of the Complete C control,
with the following additional features:
a. 75 VA transformer.
b. A removable thermostat connector.
c. Random start on return from night setback.
d. Minimized reversing value operation for
extended life and quiet operation.
e. Night setback control from low temperature
thermostat, with 2-hour override initiated by
a momentary signal from the thermostat.
f. Dry contact night setback output for digital
night setback thermostats.
g. Ability to work with heat/cool (Y, W)
thermostats.
h. Ability to work with heat pump thermostats
using O or B reversing valve control.
i. Single grounded wire to initiate night set-
back or emergency shutdown.
j. Boilerless system control can switch auto-
matically to electric heat at low loop water
temperature.
k. Control board shall allow up to 3 units to be
operated from one thermostat without any
auxiliary controls.
l. A relay to operate an external damper. The
control to be such that the damper will not
open until 30 minutes after the unit comes
back from Unoccupied mode.
m. Fan speed selection at thermostat.
n. A relay to restart a central pump or control a
24-v motorized water valve.
o. Intelligent fan speed selection based upon
thermostat demand and/or dehumidistat
signal.
6. Carrier PremierLink™ Controller:
This control will function with CCN and Com-
fortVIEW™ software. It shall also be compatible
with
Comfort
Link™ controllers. It shall be
ASHRAE 62-99 compliant and Internet ready.
It shall accept a CO
2
sensor in the conditioned
space and be Demand Control Ventilation
(DCV) ready. The communication rate must be
38.4K or faster.
7. Optional Controls:
a. Unit-mounted ACO (automatic changeover)
thermostat operating controls shall consist
of temperature setting dial knob, push but-
ton switches for Stop, Fan only, Hi fan, Lo
fan. Unit-mounted thermostats shall have a
remote sensor for sensing the return-air
temperature.
Guide specifications (cont)