Manual

4
A
B
LEAD WIRE
"B1"
ELEMENTS
CONTACTOR
(OR P2)
POWER TERMINAL BLOCK
HEATER FRONT
LEAD WIRE
"A1"
3 PHASE BLOCK
TO ELEMENTS
A
B
L
EAD WIRE
"B1"
ELEMENTS
CONTACTOR
(OR P2)
POWER TERMINAL BLOCK
HEATER FRONT
LEAD WIRE
"A1"
3 PHASE BLOCK
TO ELEMENTS
FACTORY-WIRED FOR SINGLE-PHASE POWER FIELD-WIRED FOR THREE-PHASE POWER
Figure 3a. Wiring Connections for Single-Phase and Three -Phase Power(MUH0521, MUH0581, MUH072, MUH078, MUH102 and MUH108)
B
3 PHASE BLOCK
FACTORY-WIRED FOR SINGLE-PHASE POWER
C
1
D
1
D
1
C
1
C
D
B
C
D
3 PHASE BLOCK
B
3 PHASE BLOCK
FIELD-WIRED FOR THREE-PHASE POWER
C
1
D
1
D
1
C
1
C
D
B
C
D
3 PHASE BLOCK
Figure 3b. Wiring Connections for Single-Phase and Three -Phase Power (MUH158)
T
T
MT-1
MT-2
BL ACK TO W1
RED TO R
2-STAGE
INTERNAL
THERMOSTAT
MHRT HEAT RECOVERY
THERMOSTAT OR
REMOTE FAN
SWITCH (MRFS-2)
BLACK
RED
RED
BLACK
C
RW1
W2
F 2
F 1
G
T R
T
S
S
REMOTE SUMMER FAN
SWITCH (MRFS-1)
FAN RELAY
(FOR MRFS-2 AMD MHRT)
SUMMER
FAN
SWITCH
MT-1
MT-2
2-STAGE
INTERNAL
THERMOSTAT
BLACK
RED
RED
BLACK
P2
H2
F 1
F 2
S
REMOTE SUMMER
FAN SWITCH (MRFS-1)
OR SUMMER FAN
SWITCH MCFS (MANUAL)
P1
H1
NOTES:
1. THIS STYLE CONTROL TERMINAL BOARD USED WITH MODELS
MUH0321, MUH0371, MUH0381, MUH0521, MUH0571, AND
MUH0581.
2. WHEN UNIT IS WIRED FOR SINGLE-PHASE, JUMPER H1 TO H2.
IF SINGLE-POLE THERMOSTAT IS USED WITH SINGLE-PHASE
UNIT, CONNECT THERMOSTAT LEADS TO P1 AND H1.
3. EXTERNAL LINE VOLTAGE THERMOSTATS SHOULD BE
TREATED AS SINGLE STAGE ONLY.
T
T
MT-1
MT-2
BL ACK TO W1
RED TO R
2-STAGE
INTERNAL
THERMOSTAT
MHRT HEAT RECOVERY
THERMOSTAT OR
REMOTE FAN
SWITCH (MRFS-2)
BLACK
RED
RED
BLACK
C
RW1
W2
F 2
F 1
G
T R
T
S
S
REMOTE SUMMER FAN
SWITCH (MRFS-1)
FAN RELAY
(FOR MRFS-2 AMD MHRT)
SUMMER
FAN
SWITCH
MT-1
MT-2
2-STAGE
INTERNAL
THERMOSTAT
BLACK
RED
RED
BLACK
P2
H2
F 1
F 2
S
REMOTE SUMMER
FAN SWITCH (MRFS-1)
OR SUMMER FAN
SWITCH MCFS (MANUAL)
P1
H1
Figure 5. Control Terminal Board (for Heaters With Contactors)
NOTES:
1. THIS STYLE CONTROL TERMINAL BOARD USED
WITH MODELS EXCEPT MUH0321, MUH0371,
MUH0381, MUH0521, MUH0571, AND MUH0581.
2. REMOVE JUMPER W1 TO W2 WHEN 2-STAGE THER-
MOSTAT IS USED.
3. *ONLY ONE OF THESE ACCESSORIES MAY BE
INSTALLED IN A SINGLE HEATER.
4. EXTERNAL LINE VOLTAGE THERMOSTATS
SHOULD BE TREATED AS SINGLE STAGE ONLY.
Figure 4. Control Terminal Board (for Heaters Without Contactors)