TEMPERATURE ADJUSTMENT: The thermostat is pre-set at the factory for economical ice-free use (about 40ºF,
4ºC). To adjust your specific installation temperature, turn the temperature control knob clockwise to increase the
temperature of the water (1/4 turn equals about 4ºF). Only small adjustments should be made at one time. One
complete turn is the maximum at any one time. The small light in the thermostat will glow when the element is on.
To recalibrate you will need a container of water about 40ºF (4ºC). Place the sensory bulb in water. The indicator
light should come on. If not, turn adjusting screw slowly until light comes on. This will calibrate the unit to turn on
at approximately 40ºF (4ºC). It is advisable to remove the heating unit during the summer months. The minimum
summer precaution is to turn off electricity to the unit.
WIRE AND FUSE SELECTION: Check charts below for correct fuse size (Table 2) and wire size (Table 3) for your
specific waterer. All heating units are 115V-AC unless otherwise specified.
Table 2
Fuse Size
Water
Model
Heater
Model
Ratings
Watts
At 115V
Amps
1
Waterer
Model
Heater
Model
Ratings
Watts
At 115V
Amps
1
MC32
HE1035
250
2.2
MK32
HE1035
250
2.2
MH30
HE1031
500
4.4
ML30
HE1031
500
4.4
MJ31
HE1035
250
2.2
1
For straight resistance load, Amps = Watts/Volts; therefore at 120 volts, amps are reduced.
Table 3
Voltage Drop
MINIMUM SIZED AWG COPPER WIRE REQUIRED TO ALLOW NOT MORE THAN 2% VOLTAGE DROP
1
TOTAL HEATER RATINGS115V
LENGTH OF CIRCUIT(ONE WAY) IN FEET
WATTS
AMPS
50
100
160
200
280
360
250
2.2
14
2
14
14
14
12
10
325
2.8
14
14
12
12
10
8
600
5.2
14
12
10
10
8
6
750
6.5
14
10
8
6
6
6
800
7.0
12
10
8
6
6
5
1000
8.7
12
8
6
6
5
4
1400
12.2
12
8
6
6
4
2
1600
13.9
12
8
6
4
4
2
1
Mechanical strength is not considered; overhead spans over 50 feet should be no less than #8 AWG; under 50 feet no less than
#10 AWG.
2
#14 AWG is smallest wire allowed regardless of circuit length.
CAUTION: When installing and/or servicing this unit, be certain the disconnect switch is locked in the “off position.
If your Heating Element Wires are
Black
-
Red
–
Green
(current models):
The
Green
(ground) wire is secured in the box.
The
Red
wire connects to the Red wire from the control.
The Black wire connects to the
White
(neutral) wire from the control and power source.
If your Heating Element Wires are
Red
-
White
–
Green
(current models):
The
Green
(ground) wire is secured in the box.
The
White
wire connects to the
White
(neutral) from the control and power source.
The
Red
wire connects to the
Red
wire from the control.
(If your element wires are
Black
-
White
–
Green
, wire
Black
to
Red
)
When there are multiple heating elements involved, twist the wire ends together and secure with wire nuts. Exhibit
G is the wiring illustration for Model HE10 electric unit and all current waterer models.
If you have purchased waterer Model MH30E, your waterer is supplied with heater Model HE1031A. Following is informa-
tion about your heater and other repair heaters.
1
2
3
8
MH30E HEATING ELEMENT
