Qmark MUH35 - Unit Heater - Manual (Page 3)

Wiring
Hardware Needed (See Figure 4)
You also will need the following hardware which you can pur-
chase from your local hardware store or electrical supply house:
• Enough 10 gauge copper wire to run power from the service
box to the heating unit. Copper wire must have a minimum
temperature rating of 60 degrees C. DO NOT USE
ALUMINUM WIRE WITH THIS UNIT.
• Proper wire connectors for your application. (See illustration
that follows.)
For certain applications, conduit may be required. Check local
electrical codes. Also, if you run the wiring in conduit and wish
to be able to turn the heater, be sure to purchase enough flexible
conduit to allow the heater to be turned.
1. Loosen the two screws that secure the wiring compartment
cover to the upper right hand area of the back of the heater
and remove the cover.
2. Attach the cable connector to the cover as shown above and
slide the 10 gauge wire through the cable connector. Pull
enough of the wire through the connector for making the
connections.
3. Connect the field wiring to the heater wiring as shown in
Figure 5 - Wiring Diagram.
4. After connecting the wiring, replace the wiring compartment
cover making sure none of the wires are pinched between
the cover and the heater. Tighten the screws securely.
OPERATING
INSTRUCTIONS
1. Heater must be properly installed before operation.
2. To operate the heater, first select either high or low position
on the heat selector switch, then turn the thermostat knob as
far as it will go in the clockwise direction. The indicator light
will come on and remain on as long as the heater is in the
operating mode.
3. When the room temperature reaches the desired level, slowly
turn the thermostat knob counterclockwise until the thermo-
stat clicks. The indicator light will remain on. The heater will
automatically cycle OFF and ON as needed to maintain
desired temperature.
4. To shut heater off, turn thermostat knob as far as it will go in
the counterclockwise direction until the indicator light is off.
5. The fan selector switch allows continuous or cycling fan oper-
ation by selecting either the “ON” or “Auto” position, respec-
tively.
6. It may be necessary to readjust thermostat a time or so until
exact comfort level is attained. Rotation in the clockwise
direction will increase the amount of time the heater will pro-
duce heat. Rotation in the counterclockwise direction will
reduce the amount of time the heater is on.
Automatic Fan Delay: This heater incorporates an automatic
fan delay. When the thermostat calls for heat, fan action is
delayed momentarily until the heating element is warm. When
the thermostat is satisfied, the fan continues to operate until the
heating element is cool. This action prevents circulation of cold
air, and avoids exposing unit to residual heat, thus providing
higher comfort level and prolonged element life.
NOTE: For best results, the heater should be left “ON” constant-
ly during the heating season as the thermostat, when properly
set, will maintain the desired temperature. In the full counter-
clockwise position the heater will remain off until the room tem-
perature drops well below freezing.
How To Reset Over -Temperature Safety Control:
Your heater is equipped with a manual reset safety thermal limit
control that will automatically turn the heater off and sound a
buzzer to prevent a fire if the heater overheats. This control is
located on front of the heater just above the thermostat and is
marked “PUSH TO RESET”. To reset, allow the heater to cool
then simply push the red button in until it snaps. The heater
should immediately return to normal operation.
It is important to keep this heater clean. Your heater will give you
years of service and comfort with only minimum care. To assure
efficient operation follow the simple instructions below.
DO NOT TAMPER WITH OR BYPASS ANY SAFETY LIMITS
INSIDE HEATER.
CAUTION - DO NOT CONTINUE TO ATTEMPT TO USE THE
HEATER IF THE SAFETY CONTROL REPEATEDLY OPER-
ATES AFTER BEING RESET. TO DO SO COULD PERMA-
NENTLY DAMAGE THE HEATER OR CREATE A FIRE OR
SAFETY HAZARD.
3
ELEMENTS FRONT
MIDDLE
REAR
HEAT SW. HI
LOW
1
2
3
2
3
1
AUTO
FAN SW.
ON
TERMINAL BLOCK 6 4
INDICATOR LIGHT
MANUAL RESET LIMIT
ALARM BUZZER
BLACK
GREEN
BLACK
SUPPLY LEADS
WIRING COMPARTMENT
FAN
DELAY MOTOR
L1 OFF
CYL L2
THERMOSTAT
Figure 4 - Connectors, cable, and hardware used to wire the MUH35D
Figure 5 - Wiring Diagram