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3
Anti-short cycle timer
—
Provides a
minimum off time to prevent the unit
from short cycling. The 5-minute timer
energizes when the compressor is
deenergized, resulting in a 5-minute
delay before the unit can be restarted.
Random start relay —
Ensures a
random delay in energizing each differ-
ent WSHP unit. This option minimizes
peak electrical demand during start-up
from different operating modes or after
building power outages.
High and low pressure refrigerant
protection
—
Safeguards against
unreliable unit operation and prevents
refrigerant from leaking.
Condensate overflow sensor
—
Electronic sensor mounted to the drain
pan. When condensate pan liquid
reaches an unacceptable level, the unit
is automatically deactivated and placed
in a lockout condition. The sensor
recognizes thirty continuous seconds
of overflow as a fault condition.
High and low voltage protection
—
Safety protection for excessive or low
voltage conditions.
Automatic intelligent reset
—
Unit
shall automatically restart 5 minutes
after shutdown if the fault has cleared.
Should a fault occur 3 times sequen-
tially, lockout will occur.
Accessory output
—
In applications
such as variable speed pumping, a
24 V output cycles a motorized water
valve or damper actuator with
compressor.
Performance Monitor (PM)
—
Unique feature monitors water temper-
atures to warn when the heat pump
is operating inefficiently or beyond
typical operating range. A field select-
able switch initiates a warning code on
the unit display.
Water coil freeze protection
(selectable for water or anti-
freeze)
—
Field selectable switch for
water and water/glycol solution sys-
tems initiates a fault when tempera-
tures exceed the selected limit for
30 continuous seconds.
Air coil freeze protection (check
filter operation)
—
Field selectable
switch for assessing excessive filter
pressure drop initiates a fault when
temperatures exceed the selected limit
for 30 continuous seconds.
Alarm relay setting —
Selectable
24 V or pilot duty dry contact provides
remote alarm activation.
Electric heat option
—
Output pro-
vided on the controller for operating
two stages of emergency electric heat.
Service test mode with diagnostic
LED (light-emitting diode)
—
Test
mode allows service personnel to
check the operation of the WSHP and
control system efficiently. Upon enter-
ing test mode, time delays speed up,
and the Status LED flashes a code
indicating the last fault. This mode
provides easy fault diagnosis; based on
the fault code the status LED flashes,
Carrier provided troubleshooting tables
provide easy reference to typical
problems.
LED visual output
—
An LED panel
indicates high pressure, low pressure,
low voltage, high voltage, air/water
freeze protection, condensate over-
flow, and control status.
Carrier PremierLink™ control-
ler adds reliability, efficiency,
and simplification
The PremierLink direct digital control-
ler can be ordered as a factory-installed
option. Designed and manufactured
exclusively by Carrier, the controller
can be used to actively monitor and
control all modes of operation as well
as monitor the following diagnostics
and features: unit number, zone tem-
perature, zone set point, zone humidity
set point, discharge air temperatures,
fan status, stages of heating, cooling
stages, outdoor-air temperature,
leaving-air temperature, leaving water
temperature, alarm status, and alarm
lockout condition.
This controller has 38.4K baud
communications capability and is com-
patible with
Comfort
Link™ Controls,
CCN and ComfortVIEW™ Software.
The Scrolling Marquee and Navigator
are optional tools used for program-
ming and monitoring the unit for opti-
mal performance. Adding the Carrier
CO
2
sensor in the conditioned space
provides ASHRAE 62-99 compliance
and Demand Control Ventilation
(DCV). A DCV control strategy is espe-
cially beneficial for a water source heat
pump system to minimize the energy
used to condition ventilation air. In
combination with energy efficient
Aquazone units, DCV may be the most
energy efficient approach ever devel-
oped for a water source heat pump
system.
The PremierLink peer-to-peer,
Internet ready communicating control
is designed specifically for Constant
Volume and Variable Volume Tempera-
ture applications. This comprehensive
controls system allows water source
heat pumps to be linked together, cre-
ating a fully functional HVAC (heating,
ventilation, and air conditioning) auto-
mation system.
Features/Benefits (cont)