Float Switch; Cleaning; Float Switch Check Procedure; Explanation Of Operation - Hoshizaki KMS-1230MLH Service Manual

E. Float Switch

1. Explanation of Operation

The float operates  switches within the float switch. The lower switch (black and
blue wires) is used for low water safety protection, initiating the freeze cycle refill and
terminating the freeze cycle. The upper switch (black and red wires) is used to terminate
the freeze cycle refill only. Refill will last until the upper float switch closes or the 1 minute
countdown timer ends, whichever comes first.

2. Cleaning

Depending on local water conditions, scale may build up on the float, float switch shaft
and inside the housing. Scale on the float or shaft can cause the float to stick causing
erratic operation. The float switch should be cleaned and checked before replacing.
First, disconnect the black K5 float switch connector from the control board and remove
the float switch and rubber boot from the icemaker. Remove the rubber boot from the
float switch. Twist the mechanical lock at the top of the float housing and lower out the
float and float shaft. Remove the retainer clip from the shaft and slide the float off the
shaft. Soak the switch assembly in ice machine cleaner. Wipe down the shaft, float,
housing, and rubber boot with cleaning solution. See "VI. Cleaning and Maintenance
Instructions."

3. Float Switch Check Procedure

Before replacing a float switch that you suspect is bad, make sure the float switch has
been cleaned. This procedure will help you verify your diagnosis. The float switch has
three wires. The black wire is common. The blue wire is for the lower float switch contact
and the red wire is for the upper float switch contact.
1) Disconnect the black K5 float switch connector from the control board.
) Drain the reservoir water.
3)Turn the control switch to "ICE".
4) As water fills the reservoir, the float switch contacts should close. Check continuity of
the lower float switch contacts using the black and blue wires and the upper float switch
contacts using the black and red wires. With the float positioned all the way up, both
float switch contacts should be closed. If either float switch contact fails, the assembly
should be replaced.
5) Turn the control switch to "OFF".
6) Drain the reservoir water.
7) As water drains, the float switch contacts should open. Check continuity of the upper
float switch contacts using the black and red wires and the lower float switch contacts
using the black and blue wires. With the float positioned all the way down, both float
switch contacts should be open. If either float switch contact fails, the assembly should
be replaced.
8) Reconnect the black K5 connector to the control board when finished.