Troubleshooting Chart - MYERS MDC33 Serie Manual De Instalación, Operación Y Repuestos

Hazardous voltage. Can shock, burn or
kill. The pump should always be electrically grounded to
a suitable electrical ground such as a grounded water
pipe or a properly grounded metallic raceway, or ground
wire system. Do not modify the cord or plug or cut off the
round ground pin.
9. If the pump discharge line is exposed to an outside sub-
freezing atmosphere, the portion of the line exposed
must be installed so any water remaining in the pipe will
drain to the outfall by gravity. Failure to do this can cause
the water trapped in the discharge to freeze which could
result in damage to the pump.
10. After the piping and check valve have been installed, the
unit is ready for operation.
11. Check the operation by filling the sump with water and
observing pump operation through one complete cycle.
Risk of Flooding. Failure to make this
operational check may lead to improper operation, pre-
mature failure, and flooding.
OPERATION / MAINTENANCE
Risk of electrical shock. Can burn or cause
death. Do not handle a pump or pump motor with wet hands
or when standing on a wet or damp surface, or in water.
Before attempting to check why unit has stopped operating,
disconnect power from unit.
Risk of fire and explosion. Can cause
severe injury, property damage or death. Do not use in
explosive atmospheres. Pump water only with this pump.
1. The shaft seal depends on water for lubrication and cool-
ing. Do not operate the pump unless it is submerged in
water as the seal may be damaged if allowed to run dry.
2. The motor is equipped with an automatic reset thermal
protector. If the temperature in the motor should rise
unduly, the switch will cut off all power before damage

TROUBLESHOOTING CHART

SYMPTOM
Pump won't start
or run.
Pump starts and stops
too often.
Pump won't shut off.
Pump operates but
delivers little or no
water.
PROBABLE CAUSE(S)
Blown fuse.
Low line voltage.
Defective motor.
Defective float switch.
Impeller.
Float is obstructed.
Backflow of water from
piping.
Faulty float switch.
Defective float switch.
Restricted discharge
(obstacle in piping).
Float obstructed.
Low line voltage.
Something is caught in
impeller.
Anti-airlock hole is plugged.
can be done to the motor. When the motor has cooled
sufficiently, the switch will reset automatically and restart
the motor. If the protector trips repeatedly, the pump
should be removed and checked as to cause of difficulty.
Low voltage, long extension cords, clogged impeller, very
low head or lift, etc., could cause cycling.
3. The pump will not remove all water. If a manually operated
pump is operating and suddenly no water comes out of the
discharge hose, shut the unit off immediately. The water
level is probably very low and the unit has broken prime.
3649 0200
Figure 2 – Float Switch Tether Length, Models MDC33P1,
MDC33PC1, MDC50P1 and MDC50PC1.
NOTICE: Do not change the tether length of the float switch.
The float must be able to swing through its complete arc
without interference.
AIRLOCKS
When a pump airlocks, it runs but does not move any water.
An airlock will cause the pump to overheat and fail. These
pumps have a built in anti-airlock hole. See the exploded
view on the repair parts page for the location of the hole.
Leakage from the anti-airlock hole is normal.
If you suspect an airlock, unplug the pump, clean out the
anti-airlock hole with a paper clip or a piece of wire, and
restart the pump.
CORRECTIVE ACTION
If blown, replace with a fuse of proper size.
If the voltage is under the recommended minimum, check the size
of the wiring from the main switch on the property. If OK, contact
power company or hydro authority.
Replace the pump.
Replace the float switch.
If the impeller won't turn, remove the lower pump body and locate
the source of the binding.
Remove the obstruction.
Install or replace the check valve.
Replace the float switch.
Replace the float switch.
Remove the pump and clean the pump and piping.
Remove the obstruction.
If the voltage is under the recommended minimum, check the size
of the wiring from the main switch on the property. If OK, contact
power company or hydro authority.
Clean out the impeller.
Turn off the pump, clean out the anti-airlock hole, and restart pump.
3
3-1/2"
(89 mm)