Takagi T-K3 Service Manual

T-K3 Service Manual
Ver. 1.05
23
CONFI DENTIAL
10-11. T hermistors
T-K3 Part #
#406 (Inl et)
#407 (Outlet)
#408 (Mixing)
Takagi Part #
EKK38 (Inlet)
EKK2T (Outlet)
EKK1A (Mixing)
C heckpo int
E1 (Mixing)
E2 (Outlet)
E3
(
Inlet
)
Function
F ailure event
Effects on the T-K3
if thermistor fails
Error codes when
thermistors fails.
311 (Outlet) 321 (Inlet) 331 (Mixing)
D iagnostic
Measure cold/hot water temperatures in the T-K3.
Unable to properly measure water temperatures within the T-K3.
1. Visual inspection: connection/breakage of wires and/or debris on thermistor
2. Check voltag es and r esistance ; pro pe r ra ng e of values shown below.
Color/Number of
wires
If the thermistors fail op en or shor t, er ror code appears befor e star ting operation. If
resistance values are just off, T-K3 will have temperature fluctuations in hot water.
Inlet Black(42)-Black
Outlet Black(12)-Black
Mixing Black(113)-Black
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)
0.00
5.00
10.00
15.00
20.00
25.00
20 40 60 80 100 120 140 160 180 200 220
Temperature / ºF
Resisitance / kΩ
(Mixing thermistor)
(Outlet thermistor)
(Inlet thermistor)
Blue
Black
Black
Insulating
Resistance values of thermistors as a function of

Takagi T-K3 Specifications

General

Type	Tankless
Installation Type	Indoor
Maximum BTU Input	199, 000 BTU/h
Gas Connection Size	3/4"
Vent Size	3"
Hot Water Flow Rate (at 35°C rise)	6.6 GPM
Maximum Input	199, 000 BTU/h