Servend MD 175 - Liquid Level Control

Installation and Service Manual
TROUBLESHOOTING
LIQUID LEVEL CONTROL
END
START
Does
Pump
motor
come on?
Remove red
and black
wires from
LLC.
Is pump
motor
operation
intermittent
?
Does
pump
motor
come
on?
Black and/or red probe
shorted. Remove
probes, straighten or
replace if necessary.
Short H and
C terminals
on LLC.
Does
the
pump
motor
shut
off?
Measure AC
voltage
across load
terminals on
LLC.
Check pump
motor and
wiring.
Check probe
harness, harness
connections and
water supply.
Is line
voltage
(– 10%)
present
?
Replace
LLC
Yes
No
Yes
Yes
Yes
Yes
No
No
No
No
END
START
Does
Pump
motor
come on?
Remove red
and black
wires from
LLC.
Is pump
motor
operation
intermittent
?
Does
pump
motor
come
on?
Black and/or red probe
shorted. Remove
probes, straighten or
replace if necessary.
Short H and
C terminals
on LLC.
Does
the
pump
motor
shut
off?
Measure AC
voltage
across load
terminals on
LLC.
Check pump
motor and
wiring.
Check probe
harness, harness
connections and
water supply.
Is line
voltage
(– 10%)
present
?
Replace
LLC
Yes
No
Yes
Yes
Yes
Yes
No
No
No
No