EWC Controls EWT-3900 Technical Bulletin page 3

WIRING THE RECEIVER TO THE EQUIPMENT
THERMOSTAT TERMINALS (HEAT PUMP)
SYSTEM Heat Pump 1
C 24 Volt (Common)
R
24 Volt (hot)
E/W1
Emergency 1st stage
W2
Auxiliary / Emergency 2nd Stage
Heat and Cool mode 1st stage (compressor)
Y1
No output
Y2
G
Blower/Fan Energized on call for Heat and Cool
O Energized in Cool Mode
B Energized in Heat Mode
UZC-4
Heat Pump 3H/2C
O Reversing Valve
Figure 2
BmPlus 3000
Heat Pump 2H/1C
B Reversing Valve
Figure 3
NCM-300
Gas/Elec. 1H/1C
Figure 4
Warning: There should be at least 1 hardwired system thermostat in the home or building to ensure the
ability to control the HVAC equipment in the event of a drained battery or loss of communication.
EWC Controls Inc. 385 Highway 33 Englishtown, NJ 07726 800-446-3110 FAX 732-446-5362
Heat Pump 2
2nd Stage Compressor
ZONE
T'STAT
C
C
R
R
NC
W1/E
E/W1
W2
W2
Y1
Y1
Y2
O/B Y2
G
G
O
B
ZONE
T'STAT
C
C
R
R
W/E
NC
Y
E/W1
G
W2
O/B
Y1
Y2
G
O
B
ZONE
T'STAT
C
C
R
R
NC
W/E
Y E/W1
G W2
O/B Y1
Y2
G
O
B
Copyright © 2009 EWC Controls All Rights Reserved
THERMOSTAT TERMINALS (CONVENTIONAL)
SYSTEM Single Stage
C 24 Volt (Common)
R 24 Volt (hot)
E/W1
Heat Mode 1st stage
W2 No Output
Cool mode 1st stage (compressor)
Y1
No output
Y2
G Blower/Fan Energized on call for Cool (and Heat
if HE was selected)
O No Output
B No Output
SUPPLY
R5
AIR
SENSOR
R10
2
R9
R6
1
R70
R69
ZONE 3
T'STAT
R13
W/E C
R19
W/E
R23
O/B
R24
Y
R25
R
R29
G
R30
R34
ZONE 2
T'STAT
R32
W/E C
R33
W/E
R40
O/B
R39
Y
R42
R
R43
G
R41
R44
ZONE 1 ZONE 1
R47
T'STAT T'STAT
R49
W/E C
R48
W/E
R48
O/B
R54
Y
R55
R
R54
G
R55
ONE
R50 ZONE
R61
R63
R62
Figure 5
R65
E-Mail- info@ewccontrols.com
Multistage
Heat Mode 2nd stage
2nd Stage Compressor
FULLY
ZONED
NCM-3000
C
R
NC
E/W1
W2
Y1
Y2
G
O
B
C
R
NC
E/W1
W2
Y1
Y2
G
O
B
C
R
RC
E
O/B
AUX
L
Y2
Y
G
For detailed wiring info
refer to NCM-300 TB-226
3