A.O. Smith 240 T-H3J Service Manual page 17

Check-
Part and Description
point
F Remote controller
G Fan motor
H1 Gas proportional valve
H2 Flow sensor
I
Flame rod
J Flow adjustment valve
Bypass valve
J1
540 (T-H3) models only
K1
K2
L Temperature controller
240 (T-H3J), 340 (T-H3S) and 540 (T-H3) models Service Manial
Color of wires
White – Black
Red - Blue
Yellow - Blue
Orange - Blue
White - red
Red - Black
White - Black
Yellow - AFR rod
(Between the AFR rod and
the computer board)
Orange - Flame rod
the computer board)
Red - Black
Brown - Red
White - White
White - White
White – Black
17
Page
CONFIDENTIAL
Ver. 1.00
Normal range
11 to 25 VDC
132 to 192 VDC
13 to 17 VDC
2.0 to 6.5 VDC
1.0 to 15 VDC
(during operation)
and
4.0 to 5.5 VDC
1.0 to 4.0 VDC (pulse)
(more than 18 Hz)
(during operation)
(during operation)
7.0 to 16 VDC and
3.0 to 11 VDC and
See table on p. 19
and
11 to 25 VDC