Relay Configurations - Carrier AQUAZONE 50PTH Installation And Service Instructions Manual

ground loop systems will not experience overcooling of the
supply-air temperature. If overcooling of the space is a con-
cern (e.g., computer room well water application), auxiliary
heating may be required to maintain space temperature
when the unit is operating in the dehumidification mode.
Water source heat pumps with HWR should not be used as
makeup air units. These applications should use equipment
specifically designed for makeup air.
HWR COMPONENT FUNCTIONS — The proportional
controller operates on 24 VAC power supply and automatically
adjusts the water valve based on the supply-air sensor. The
supply-air sensor senses supply-air temperature at the blower
inlet, providing the input signal necessary for the proportional
control to drive the motorized valve during the reheat mode of
operation. The motorized valve is a proportional actuator/three-
way valve combination used to divert the condenser water
from the coax to the hydronic reheat coil during the reheat
mode of operation. The proportional controller sends a signal
to the motorized valve based on the supply-air temperature
reading from the supply air sensor.
The loop pump circulates condenser water through the hy-
dronic reheat coil during the reheat mode of operation (refer to
Fig. 33). In this application, the loop pump is only energized
during the reheat mode of operation. The hydronic coil is uti-
lized during the reheat mode of operation to reheat the air to the
set point of the proportional controller. Condenser water is di-
verted by the motorized valve and pumped through the hydron-
ic coil by the loop pump in proportion to the control set point.
The amount of reheating is dependent on the set point and how
far from the set point the supply air temperature is. The factory
set point is 70 to 75 F, generally considered "neutral" air.
Deluxe D Control Accessory Relay Configura-
The following accessory relay settings are applica-
tions —
ble for Deluxe D control:
MODE
No Demand
Fan Only
Cooling Stage 1
Cooling Stage 2
†
Cooling and Dehumidistat
Dehumidistat Only
Heating Stage 1
Heating Stage 2
Heating and Dehumidistat**
*Not applicable for single stage units; Full load operation for dual capacity
units.
†Cooling input takes priority over dehumidify input.
Table 17 — HWR Operating Modes
INPUT
O G Y1
On/Off Off Off
On/Off On Off
On On On
On On On
On On On
On/Off Off Off
Off On On
Off On On
Off On On
CYCLE WITH FAN — In this configuration, the accessory
relay 1 will be ON any time the Fan Enable relay is on.
CYCLE WITH COMPRESSOR — In this configuration, the
accessory relay 2 will be ON any time the Compressor relay is
on.
DIGITAL NIGHT SET BACK (NSB) — In this configura-
tion, the relay will be ON if the NSB input is connected to
ground C.
NOTE: If there are no relays configured for digital NSB, then
the NSB and override (OVR) inputs are automatically config-
ured for mechanical operation.
MECHANICAL NIGHT SET BACK — When NSB input is
connected to ground C, all thermostat inputs are ignored. A
thermostat set back heating call will then be connected to the
OVR input. If OVR input becomes active, then the Deluxe D
control will enter night low limit (NLL) staged heating mode.
The NLL staged heating mode will then provide heating dur-
ing the NSB period.
WATER VALVE (SLOW OPENING) — If relay is configured
for Water Valve (slow opening), the relay will start 60 seconds
prior to starting compressor relay.
OUTSIDE AIR DAMPER (OAD) — If relay is configured for
OAD, the relay will normally be ON any time the Fan Enable
relay is energized. The relay will not start for 30 minutes fol-
lowing a return to normal mode from NSB, when NSB is no
longer connected to ground C. After 30 minutes, the relay will
start if the Fan Enable is set to ON.
To avoid equipment damage, DO NOT leave system filled
in a building without heat during the winter unless anti-
freeze is added to system water. Condenser coils never
fully drain by themselves and will freeze unless winterized
with antifreeze.
Y2* H O
Off Off On/Off
Off Off On/Off
Off Off On
On Off On
On/Off On On
Off On On
Off Off Off
On Off Off
On/Off On Off
**Deluxe D is programmed to ignore the H demand when the unit is in heating
mode.
NOTE: On/Off is either on or off.
32
CAUTION
OUTPUT
G Y1 Y2* Reheat
Off Off Off
On Off Off
On On Off
On On On
On On On/Off
On On On
On On Off
On On On
On On On/Off
Off
Off
Off
Off
Off
On
Off
Off
Off