Specifications

TroubleshootingGuide
15|Page
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ERRORCODE311:OUTPUTTHE RMISTOR
1) Checkthatthewireconnectionsaresecureandfreeof
burnsorcuts.Theoutputthermistorislocatedonthe
heatexchangerontherightside.

2) Checktheresistancevalue;itshouldbeabout9.0kΩat
roomtemperature(about74°F).
3) Cleanthethermistor.
a. Draintheunitofwater.Seep.22. 
b. Removethefastenerholdingtheoutput
thermistorandpulloutthesensorprobe.Clean
theprobetoasilverfinish.Do
notlosetherubber
o‐ringthatwrapsaroundthissensor.
c. Replaceandtest.
4) Iftheerrorcodepersists,replacethethermistor.

ERRORCODE321:INLETTHERMISTOR
1) Checkthatthewireconnectionsaresecureandfreeofburnsorcuts.Theinletthermistoris
embeddedinthewaterinletconnection.
2) Checktheresistancevalue;itshouldbeabout9.0kΩatroomtemperature(about74°F).
3) Cleanthethermistor.
a. Draintheunitofwater.Seep.
22.
b. Removethecomputerboardtoaccesstheinletthermistor.Thecomputerisfixedinplacebya
singlescrewatthetopoftheboard.
c. Removethescrew,pulloutthesensorprobe.Cleantheprobetoasilverfinish.Donotlosethe
rubbero‐ring
thatwrapsaroundthissensor.
d. Replaceandtest.

4) Iftheerrorcodepersists,replacethethermistor.

ERRORCODE331:MIXINGTHERMISTOR 
1) Checkthatthewireconnectionsaresecureandfreeofburnsorcuts.Themixingthermistoris
embeddedinthewateroutletconnection.
2) Checktheresistancevalue;itshouldbeabout9.0kΩatroomtemperature(about74°F).
3) Cleanthethermistor.
a. Draintheunitofwater.Seep.
22.
b. Removethecomputerboardtoaccessthemixingthermistor.Thecomputeris fixedinplaceby
asinglescrewatthetopoftheboard.
c. Removethescrew,pulloutthesensorprobe.Cleantheprobetoasilverfinish.Donotlosethe
redrubbero‐
ringthatwrapsaroundthissensor.
d. Replaceandtest.
4) Iftheerrorcodepersists,replacethethermistor.
OutputThermistors
InletThermistor
MixingThermistor
MixingThermistor
Figure8
Figure9