Technical information

12/01/02
2. THERMISTOR: Check out the thermistor mounting and
check resistance versus temperature per this chart:
THERMISTOR TEMPERATURE / RESISTANCE
SENSOR TEMP (F°) RESISTANCE (K OHMS)
0 14.4
10 10.6
32 6.0
50 3.9
70 2.5
90 1.6
The symptoms of a bad thermistor are:
OPEN: 20 minute harvest cycle. The unit will shut
down on a 2 beep safety after 2 consecutive 20
minute harvest cycles.
SHORTED: Unit locks out on manual reset high temp-
erature 1 beep safety in this case.
High Temperature Safety: If evaporator reaches 127°F
the thermistor signal (500 ohms) shuts down the unit on
this manual reset. A 1 beep alarm will occur.
To reset this
alarm, press the Alarm Reset button on the board
with power ON.
Then check the items listed on the control
board label for a 1 beep alarm.
UNIVERSAL REPLACEMENT FLOAT SWITCH:
There are two styles of KM float switches. One has no
hole in the outside pipe and one has a hole in the outside
pipe. Float switch number 4A0886-02 can be used as a
universal replacement on any KM unit. Simply seal off the
small hole in the outside tube with silicone or a seal cap
from 3/8” refrigeration tubing if it is not needed.
CONNECTOR BOOT:
The float switch boot will sometimes collect scale deposits
since it is in a low area of the water circuit. The boot should
be cleaned thoroughly during scheduled maintenance. Due
to age and high amounts of chlorine in the local water
supply, it can also deteriorate and may cup upward in the
middle holding the float up . In this case, the boot should be
replaced. Order part number 426799-01 as universal re-
placement part and cut the tube to length as needed.
Universal float boot
# 426799-01
(Cut tube to length)
41
12/20/03
2/20/03