Diagnosing A Manitowoc Water Pump January 22 2015, 4 Comments

Every commercial ice machine has a water pump, so Manitowoc ice makers are no different.  The water pump works by taking the water from the water trough, pushing up through the tubing, out and over the evaporator through the distribution tube.  It’s important for the water pump to be strong enough to push an even flow of water, but not too strong to cause the stream of water to miss cascading down the evaporator.  To troubleshoot a Manitowoc water pump, follow this guide for signs you may need a new ice machine part.

Water pumps consist of 2 main components, the motor and the impeller.  The motor turns, spinning the impeller, and sucking water out of the trough.  The force then pushes water to the top of the ice machine, which allows Manitowoc to make ice with a vertical evaporator.

Proper voltage must be supplied to the water pump for it to work efficiently.  If too low of voltage is supplied, the motor will not be strong enough to pump the water.  However, too high of voltage could cause the motor to burn up.  Checking to make sure you have the proper voltage at the ice machine is important for not only the water pump, but all electrical ice maker parts.

If no water is being pumped over the evaporator, first make sure that there is water in the trough.  An absence of water could also cause the water pump to be damaged.  However, if there is water in the trough, but none pumping, check tubing and the impeller for debris.  Hard scale can build up in the impeller, causing it to not turn.  Also, debris can block the screen, keeping a constant water supply from being pumped.

A pump exposed to prolonged blockage could cause the motor to burn up and become damaged.  Replacement of the entire water pump is required, Manitowoc does not offer the individual components.  A broken impeller or screen must be repaired with an entirely new pump assembly.  If a water pump is struggling it will become very warm and hot to the touch.  A water pump that is exceptionally hot is a sign that failure is imminent.

It’s also possible, on older ice machines, that the water pump has become too aggressive.  Over the years a pump may become too strong and force water out of the distribution tube too fast.  This causes the water to actually miss cascading down the evaporator.  To fix this, restrict water flow in the vinyl tube leading to the distribution tube or replace the water pump itself.  Restriction of the tubing can be done with a simple bar clamp or hose clamp.

If the water pump is not running at all, troubleshoot the problem by testing the voltage at the water pump plug.  The voltage at the water pump should match the voltage of your ice machine.  So, if you have a 115v Manitowoc ice machine, the water pump should also be 115v.  Knowing the proper sequence of events will assist in knowing when to check the voltage.  The water pump will not run all the time, only when the board calls for it.  Different model Manitowoc ice makers will call for the water pump at different times.  The water pump may also be used for the dump cycle and not just transporting water over the evaporator.

To confirm the time the water pump should be energized, please consult your service technicians handbook.  Or, if you have any questions about diagnosing a Manitowoc water pump or other topics covered in this article, send us an email at sales@icemakerpartsshop.com.