Heat Controller HEV Series Installation, Operation & Maintenance Manual page 26

Installation, Operation & Maintenance
Thermostat Installation
The thermostat should be located on an interior wall in a
larger room, away from supply duct drafts. DO NOT locate
the thermostat in areas subject to sunlight, drafts or on
external walls. The wire access hole behind the thermostat
may in certain cases need to be sealed to prevent erroneous
temperature measurement. Position the thermostat back
plate against the wall so that it appears level and so the
thermostat wires protrude through the middle of the back
plate. Mark the position of the back plate mounting holes
and drill holes with a 3/16" (5mm) bit. Install supplied
anchors and secure plate to the wall. Thermostat wire must
be 18 AWG wire. Wire the appropriate thermostat as shown
in Figures 25a and 25b to the low voltage terminal strip
on the DXM2 control board. Practically any heat pump
thermostat will work with these units, provided it has the
correct number of heating and cooling stages.
CAUTION!
CAUTION! Refrigerant pressure activated water regulating
valves should never be used with ClimateMaster
equipment.
Figure 23a: Communicating Thermostat Connection to
DXM2 Control
ATC32U01 Thermostat
R
24Vac Hot
A+
Comm +
B-
Comm -
C
24Vac Common
Figure 23b: Conventional 3 Heat / 2 Cool Thermostat
Figure 24b: Conventional 3 Heat / 2 Cool Thermostat
Connection to DXM2 Control
Connection to DXM2 Control
Thermostat
Y1
Compressor
Y2
Compressor Stage 2
W
Auxiliary Heat
DH
Dehumidification
O
Reversing Valve
G
Fan
R
24Vac Hot
C
24Vac Common
L
Fault LED
Notes:
1) ECM automatic dehumidification mode operates with dehumidification airflows
in the cooling mode when the dehumidification output from thermostat is active.
Normal heating and cooling airflows are not affected.
2) DXM2 board DIP switch S2-7 must be in the auto dehumidification mode for
automatic dehumidification
HEV/H SERIES
ELECTRICAL - THERMOSTAT WIRING
DXM2
24V
A+
B-
Gnd
DXM2
Board
Y1
Y2
W
H
O
G
R
C
AL1
Figure 24: Typical Thermostat 2 Heat/1 Cool
Connection to DXM2 Control
ATM21U01 Thermostat
Compressor
Heating Stage 2
Reversing Valve
Fan
24Vac Hot
24Vac Common
Fault LED
(Using 2 Heat / 1 Cool thermostat is not
recommended if maximum efficiency is desired)
26
Heat Controller, Inc.
DXM2
Y
Y2/W
O
G
R
C
L AL1
Y1
W
O
G
R
C