Qmark MUH - Horizontal / Downflow Unit Heaters - Manual

3. Install leads to terminal block. Refer to wiring diagram, Figure 6, for
wiring procedure on 3KW and 5KW units (208V, 240V, and 277V
only). Refer to wiring diagram, Figure 7, for wiring procedure on all
other heaters.
INSTALLATION OF REMOTE FAN SWITCH
RFS1
The Remote Fan Switch is mounted external and remote from the unit
heater. The voltage of the remote fan switch circuit is the same as the
supply voltage to the heater.
1. Use 14 gauge copper, NEC Class 1, 600V rated insulated wire.
Wiring must meet all local and NEC requirements.
2. Install the remote fan switch in a standard wall box in any conve-
nient location that is protected from traffic or other accidental dam-
age.
3. Connect the 14 gauge copper field wire to the switch lead wires with
suitable connectors.
4. A 1/2-inch (12.7mm) knockout is provided in the back of the heater
adjacent to the control terminal board. Use a crimp-on terminal suit-
able for No. 8 screw on the control terminal board. Connect one field
wire terminated lead to terminal F1 and the other terminated lead to
terminal F2. Refer to Figure 6 for connecting to heaters without built-
in contactors. Refer to Figure 7 for connecting to heaters equipped
with built-in contactors.
INSTALLATION OF REMOTE PILOT DUTY FAN
SWITCH RFS2 (Including Wall Switch and Relay)
The Remote Fan Switch is mounted external and remote from the unit
heater.
1. Use 18 gauge (min.), NEC Class 1, 600V wiring that meets all local
and NEC requirements.
2. Install the remote fan switch in a standard wall box in any conve-
nient location that is protected from traffic or other accidental dam-
age.
3. Connect the field wire to the switch lead wires with suitable connec-
tors.
4. A 1/2-inch (12.7mm) knockout is provided in the back of the heater
adjacent to the control terminal board. Use a crimp-on terminal
suitable for No. 8 screw on the control terminal board. Connect one
field wire terminated lead to terminal "R" and the other terminated
field wire lead to terminal "G". Refer to Figure 7.
5. Install relay as indicated below.
INSTALLATION OF FAN RELAY (For RFS2)
1. Mount relay in control compartment with two No. 8 mounting screws
as shown in Figure 4.
2. Connect the lead wires from the relay to the control terminal board
as shown in Figure 7. Each lead wire is marked for proper terminal
location; connect the lead wires as indicated.
INSTALLATION OF INTERNAL THERMOSTAT
MT1, MT2, 2E569, 3UG72 2YU33 and 2YU95
1. Remove 5/16" (7.9mm) knockout from back of heater and route cap-
illary tube through hole (Figure 1).
2. Install thermostat bulb clip in slot provided in the back panel of the
heater. Secure capillary bulb in clip.
3. Press on left side of logo label on front of heater to locate shaft and
screw holes. Punch holes through label.
4. Install thermostat as shown in Figure 2, coiling any excess capillary
tubing inside the heater.
5. Refer to wiring diagram, Figure 6, for wiring procedure on 3KW and
5KW (208V, 240V and 277V only). Refer to wiring diagram, Figure
7, for wiring procedure on all other heaters.
6. Remove backing from label (supplied) and install over thermostat
shaft. Install knob by pushing onto the thermostat shaft.
THERMOSTAT
BULB CLIP
5/16" (7.9mm)
DIAMETER
KNOCKOUT
BACK OF HEATER
Figure 1. Installation of Internal Thermostat Capillary
TO PREVENT POSSIBLE ELECTRICAL SHORT CIRCUIT OR
FIRE, KEEP CAPILLARY TUBING AWAY FROM INTERNAL
ELECTRICAL COMPONENTS.
WARNING
KNOB
MOUNTING
SCREWS (2)
FRONT OF
HEATER
THERMOSTAT
Figure 2. Installation of Internal Thermostat
Electrical Accessories
For MUH, HUHAA, Dayton 3UF77 - 3UF98 and
2YU58-2YU81, 3END3 and 3END4 Series Unit Heaters
INSTALLATION OF FAN SWITCH
FS, 3UG03 and 2YU82
1. Remove 1/2" (12.7mm) knockout (located between ON and AUTO)
from back of heater (Figure 3).
2. Install manual fan switch as shown in Figure 3. (Note orientation of
slot in switch nozzle. Locate slot in the switch nozzle towards the
"AUTO" position.) Be sure to use lockwasher to prevent rotation of
switch.
KNURLED
NUT
ON
AUTO
FAN
SWITCH
SLOT DOWN
HEX NUT
LOCKWASHER
BACK OF
HEATER
Figure 3. Installation of Fan Switch
F
R
O
N
T
O
F
H
E
A
T
E
R
CONTROL TERMINAL BOARD
RELAY
NO. 8
MOUNTING SCREWS
Figure 4. Installation of Fan Relay
1