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Tankless Troubleshooting Manual
Explanation: Combustion Fan failure. Fan motor does not work properly. At a minimum check
the following:
5.
6.
7.
8.
Ensure fan motor will turn freely. Motor will operate with a small amount of restriction.
Check there is some volume of air from the flue outlet at the top of the heater.
Check wiring harness to motor for damaged and/or loose connections.
Check Molex connections of the PCB.
No
Does the Fan
Motor have
sufficient
voltage?
Does the Fan
operate?
No
Replace Printed Circuit
Board
Yes
The water heater appears to be
normal. Attempt to operate
again.
Yes
%
Is there any
pulse output
from the Fan
Motor?
'
Replace Fan Assembly
Yes
+
(
,
/
0
.
(
0
(
%
1
$
*
.
(
+
&
-
2
%
(
(
'
"
%
!
%
No
59
"
$
#
)
Replace Printed Circuit Board
&
SVC 810 Tankless Troubleshooting Manual
Yes
When motor
operates, is the
voltage to the
water control
OK?
No
Replace the Printed Circuit Board
6
4
7
7
4
Replace the Water Control Assembly
Explanation: Gas Inlet Solenoid Valve (G.I.S.V) fault. Check gas inlet solenoid valve wiring
harnesses for loose or damage terminals; and connection K to the circuit board is tight.
No
Is there power
to the G.I.S.V.
valve?
Replace the Printed Circuit Board
5
9
8
%
(
1
%
6
&
%
Yes
Replace G.I.S.V. Valve
Explanation: Flame Sensing Device fault. The Flame Probes are sensing the presence of flame
when there is not suppose to be any flame.
See and follow the same procedure as used in Error Code 51.
60