Information contained in this document is subject to change without notice.
13
238-54367-00A REV 09/21
SECTION 7: TROUBLESHOOTING
ENSURE POWER TO THE UNIT IS “OFF” BEFORE REMOVING THE PROTECTIVE COVER
FOR ANY REASON.
For status resolution, please consult the table for your heater model below.
KwickShot® Thermostatic models
Code
Name
Possible causes
Heater response
Possible solutions
F23
No heat
- element failure
- ECO tripped/malfunctioning
- triac(s) failed open
- relay/contactor malfunctioning
- control board failure
- inlet water supply out of spec
Heating will be disabled after 30
seconds of continuous no heat
condition.
- measure element resistance
with the unit completely turned off
F24
Low heat
- undervoltage
- triac(s) failed open
- control board failure
- inlet/outlet thermistor(s) failure
Heating enabled, reduced
performance (lower outlet
temperature).
- verify power supply (voltage)
while heater is running
F33
Residual heat
- internal water temperature elevated
without flow
- both triacs failed closed
Heating disabled until outlet
temperature falls below the
reactivation temperature (see
default parameters table).
- run water through the unit
F34
Overvoltage
- inlet voltage is too high compared to
the stated heater specifications
Heating enabled, reduced
performance (higher outlet
temperature).
- have certified personnel verify
the inlet voltage
- provide voltage within specified
range
F36
Undervoltage
- inlet voltage is too low compared to
the stated heater specifications
Heating enabled, reduced
performance (lower outlet
temperature).
- have certified personnel verify
the inlet voltage
- provide voltage within specified
range
F38
High flow
- flow is too high to heat the water to
setpoint temperature
Heating enabled; unit operates
as intended (lower outlet
temperature possible).
- reduce flow (outlet flow
restrictor, faucet aerator)
F47
Inlet
thermistor
failure
- inlet thermistor interrupted or
disconnected
Heating enabled based on
default inlet temperature setting
(see default parameters table;
higher/lower outlet temperature
possible).
- inspect connections/wiring of
inlet thermistor
F48
Outlet
thermistor
failure
- outlet thermistor interrupted or
disconnected
Heating enabled; auto calibration
disabled.
- inspect connections/wiring of
outlet thermistor
F64
Freeze
warning
- inlet temperature is too low (below
35
°
F)
Heating disabled while condition
is present.
- increase inlet water temperature
above 35°F
Status code
Model suffix
Default values
F33
T, ML
Trip
170°F
Reactivation
140°F
KwickShot® Thermostatic models