User Guide

41
Design Guide - HZH/HZV Series
Table 2: Humidistat/Dehumidistat Logic and DXM (2.1, 2.2., 2.3) DIP Settings
Sensor 2.1 2.2 2.3 Logic Reheat (ON) - H Reheat (OFF) - H
Humidistat OFF OFF OFF Reverse 0 VAC 24 VAC
Dehumidistat OFF ON OFF Standard 24 VAC 0 VAC
1
Cooling input takes priority over dehumidify input.
2
DXM is programmed to ignore the H demand when the unit is in heating mode.
3
N/A for single stage units; Full load operation for dual capacity units.
4
ON/OFF = Either ON or OFF.
Mode
Input Output
O G Y1 Y2
3
H O G Y1 Y2
3
Reheat
No Demand ON/OFF OFF OFF OFF OFF ON/OFF OFF OFF OFF OFF
Fan Only ON/OFF ON OFF OFF OFF ON/OFF ON OFF OFF OFF
Cooling 1st Stage ON ON ON OFF OFF ON ON ON OFF OFF
Cooling 2nd Stage ON ON ON ON OFF ON ON ON ON OFF
Cooling & Dehumidistat
1
ON ON ON ON/OFF ON ON ON ON ON/OFF OFF
Dehumidistat Only ON/OFF OFF OFF OFF ON ON ON ON ON ON
Heating 1st Stage OFF ON ON OFF OFF OFF ON ON OFF OFF
Heating 2nd Stage OFF ON ON ON OFF OFF ON ON ON OFF
Heating & Dehumidistat
2
OFF ON ON ON/OFF ON OFF ON ON ON/OFF OFF
Table 3: ClimaDry
®
II Operating Modes
ClimaDry
®
II - Sequence of Operation
ClimaDry® II Sequence of Operation - A heat pump
equipped with ClimaDry® II can operate in three
modes; cooling, cooling with reheat (dehumidification),
and heating. The cooling/heating modes are like any
other Comfort-Aire/Century 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 required with the ClimaDry® II 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 dehumidification function for
activation. The DXM board is configured to work with
either a humidistat or dehumidistat input to terminal
“H”. Upon receiving an “H” input, the DXM board will
activate the cooling mode and engage reheat. Table 4
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 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.
1st Stage Cooling: A simultaneous call from (G), (Y1), (Y2),
and (O) to the (G), (Y1), (Y2), (O/W2) terminals of the
DXM control board will bring the unit on in 2nd Stage
Cooling. When the call is satisfied at the thermostat,
the unit will continue to run in the 1st Stage Cooling
untill the 1st Stage Cooling call is removed or satisfied,
shutting down the unit.
2nd 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.