Takagi T-K3 Service Manual page 23

10-11. Thermistors
#406 (Inlet)
T-K3 Part # #407 (Outlet)
#408 (Mixing)
Function Measure c old/hot water temperatures in the T-K3.
Unable to properly measure water temperatures within the T-K3.
Failure event
If the thermistors fail open or short, error code appears before starting operation. If
Effects on the T-K3
resistance values are just off, T-K3 will have temperature fluctuations in hot water.
if thermistor fails
Error codes when
311 (Outlet)
thermistors fails.
1. Visual inspection: connection/breakage of wires and/or debris on thermistor
Diagnostic
2. Check voltages and resistance; proper range of values shown below.
Color/Number of
wires
Resistance values of thermistors as a function of
25.00
20.00
15.00
10.00
5.00
0.00
20 40
Takagi Part #
321 (Inlet)
Inlet Black(42)-Black
Outlet Black(12)-Black
Mixing Black(113)-Black
Insulating
60 80 100
Temperature / ºF
EKK38 (Inlet)
EKK2T (Outlet) Checkpoint
EKK1A (Mixing)
331 (Mixing)
68˚F (20℃) 9.0~13KΩ
122 ˚ F (50 ℃ ) 3.3~4.4KΩ
176 ˚ F (80 ℃ ) 1.4~1.8KΩ
(see table below for more resistance values)
Black
(Inlet thermistor)
Blue
(Outlet thermistor)
Black
(Mixing thermistor)
120 140 160
23
CONFIDENTIAL
T-K3 Servi c e Manual
Ver. 1.05
E1 (Mixing)
E2 (Outlet)
E3 (Inlet)
180 200 220