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ClimateMaster Water-Source Heat Pumps
CLIMATEMASTER WATER-SOURCE HEAT PUMPS
Tranquility
®
30 (TT) Series
Rev.: 07/18/13
ClimaDry
®
Sequence Of Operation
A heat pump equipped with ClimaDry
®
can operate in
three modes, cooling, cooling with reheat, and heating. The
cooling/heating modes are like any other ClimateMaster
WSHP. The reversing valve (“O” signal) is energized in
cooling, along with the compressor contactor(s) and
blower relay. In the heating mode the reversing valve
is de-energized. Almost any thermostat will activate
the heat pump in heating or cooling modes. The DXM
microprocessor board, which is standard with the ClimaDry
®
option, will accept either heat pump (Y,O) thermostats or
non-heat pump (Y,W) thermostats.
The reheat mode requires either a separate humidistat/
dehumidistat or a thermostat that has an integrated
dehumidifi cation function for activation. The DXM board is
confi gured to work with either a humidistat or dehumidistat
input to terminal “H” (DIP switch settings for the DXM
board are shown below in table 7). Upon receiving an “H”
input, the DXM board will activate the cooling mode and
engage reheat. Table 8 shows the relationship between
thermostat input signals and unit operation.
There are four operational inputs for single stage units
and six operational inputs for dual stage units:
-Fan Only
-1st Stage Cooling
-2nd Stage Cooling
-1st Stage Heating
-2nd Stage Heating
-Reheat Mode
• Fan Only: A (G) call from the thermostat to the (G
terminal of the DXM control board will bring the unit
on in fan only mode.
• 1st Stage Cooling: A simultaneous call from (G),
(Y1), and (O) to the (G), (Y1), (O/W2) terminals of the
DXM control board will bring the unit on in 1st Stage
Cooling.
• 2nd Stage Cooling: A simultaneous call from (G), (Y1),
(Y2), and (O) to the (G), (Y1), (Y2), and (O/W2)terminals
of the DXM control board will bring the unit on in
2nd Stage Cooling. When the call is satisfi ed at the
thermostat the unit will continue to run in 1st Stage
Cooling until the 1st Stage Cooling call is removed or
satisfi ed, shutting down the unit. Note: Not all units
have two-stage cooling functionality (e.g. GC series
units).
• 1st Stage Heating: A simultaneous call from (G) and
(Y1) to the (G) and (Y1) terminals of the DXM control
board will bring the unit on in 1st Stage Heating.
• 2nd Stage Heating: A simultaneous call from (G), (Y1),
and (Y2) to the (G), (Y1), and (Y2) terminals of the
DXM control board will bring the unit on in 2nd Stage
Heating. When the call is satisfi ed at the thermostat
the unit will continue to run in 1st Stage Heating
until the call is removed or satisfi ed, shutting down
the unit. NOTE: Not all units have two-stage heating
functionality (e.g. GC series units).
• Reheat Mode: A call from the Humidistat/Dehumidistat
to the (H) terminal of the DXM control board will
bring the unit on in Reheat Mode if there is no call
for cooling at the thermostat. When the Humidistat
Dehumidifi cation call is removed or satisfi ed the
unit will shut down. Note: Cooling always overrides
Reheat Mode. In the Cooling mode, the unit cools
and dehumidifi es. If the cooling thermostat is satisfi ed
but there is still a call for dehumidifi cation, the unit will
continue to operate in Reheat Mode.
ClimaDry
®
Component Functions
The ClimaDry
®
option consists of the following
components:
• Proportional Controller
• Supply Air Sensor
• Motorized Valve
• Loop Pump
• Hydronic Coil
The Proportional Controller operates on 24 VAC power
supply and automatically adjusts the water valve based
upon 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 of the supply
air sensor.
ClimaDry
®
Modulating Reheat Option
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