71
I
~
~
YES
~
Go to 8
~
fjJ
YES
~Vaillant
HEATING,CONTROLS,HOTWATER.
I~O~
(a) Check standing and
working gas pressure at
appliance inlet.
T Pic25
~
(c) Check voltage across
diaphragm pump (approx 6v
DC) withNTC disconnected.
T Pic27
J
(b) Check diaphragm pump
operating tubes and throttle
jet clear.
T Pic26
NO~
(a) TestNTC/Elebtronic
board.
Pull off NTC wire (from
D.H.W. overheat) touch it
on chassis, if burner goes
off, change NTC.
T Pic29
(d) Check burner pressure
settings low and high fire rate.
T Pic28
(e) Check and/or replace gas
operator.
If burner stays on change
electronic board.
(The gas operator may be
stuck open eg debris. This
symptom is very unlikely
but can be checked by
pulling off the wire to
operator. Ifburner remains
alight then change
operator).
To Next Page
Loading...
