Rinnai REU-2007W, Service Manual

Page: 53 / 69

Infinity REU-2007,2008,2408,2424 - 48 - ©Rinnai
D. Can not adjust
water temperature.
4. Check water flow
servo.
i) Measure resistance
between red-blue water
flow servo connector I
1
.
10 ~ 30
Yes Go to D-4-ii).
No Replace water flow
servo with sensor. 42
ii) Measure voltage
between orange (+) -
grey (-) water flow servo
connector I
1
.
DC11~13V Yes Go to -4-iii).
No Replace PCB. 43
iii) Measure voltage
between brown-grey
water flow servo
connector I
1
(don’t turn
water ON).
DC4 ~ 6V Yes Go to D-4-iv).
No Replace water flow
servo with sensor. 44
iv) Measure voltage
between yellow-grey
water flow servo
connector I
1
(don’t turn
water ON).
Is voltage < DC
0.5V Yes Normal
No Replace water flow
servo with sensor. 45
E. Anti-frost heater
does not work.
1. Check anti-frost
heater.
i) * Disconnect
connector J
3
; measure
resistance between blue-
blue (water valve)
950~1050
(2424,2408,2008)
590~600
(2007)
Yes Go to E-1-ii).
No Replace anti-frost
heater (assy). 46
ii) * Disconnect
connectors J
3
; measure
resistance between blue-
blue. (heat exchanger).
135~170
Yes Go to E-2.
No Replace anti-frost B
(assy). 47
2. Check frost
sensing switch.
Disconnect connector f
3
;
measure the resistance
between blue-blue.
Atmospheric
temperature less than
4
C.
Is resistance <
1
Yes Check wiring.
No Replace frost
sensing switch. 48
Nature of Fault
Examination
Point
Diagnostic Point Values Y/N Action
Repair
N
o
Ω
Ω
Ω
Ω
± °
Ω