Savio 20/1 MFS User Manual page 45

Fault finding
ref. 1 Supply voltage should be indicated when the
appliance is started and when the thermostat or timer
is open.
Set the tester to VAC
ref. 2 Supply voltage should be indicated when power is
supplied to the electronic regulation p.c.b.
Set the tester to VAC
ref. 3 Supply voltage should be indicated when power is
supplied to the pump.
Set the tester to VAC
ref. 4 A fuse generally blows because of an overload. To lo-
cate the cause, disconnect the components con-
nected to the board and measure their electric resis-
tance; see ref. 5.
Spare fuses are available in housing of the electronic regula-
tion p.c.b.
ref. 5 To check a winding, disconnect the winding from its
circuit and measure the resistance in the winding (set
tester to ohm):
Pump
upper on---off operator
lower on---off operator
Fan
3---way valve
ref. 6 To check the continuity of a cable, disconnect the cable
from its circuit and measure the resistance when the
two ends of the cable are connected. The resistance
should be zero ohms with the tester set to the ohms
function.
.
Set tester to ohm
ref. 7
ref. 8
ohm
12500
11500
10500
9500
8500
7500
6500
5500
4500
3500
2500
1500
500
ref. 9
180 ohm
4 000 ohm
870 ohm
ref. 10
100 ohm
1 700 ohm
ref. 11
rev. 17.09.93
Disconnect the terminals from the microswitch on the
flow switch and measure the resistance. When the
appliance is switched off the resistance should be in-
finity; when the appliance is switched on the resistance
should go to zero ohms. Set tester to ohm
To avoid electric shocks carefully insulate the elec-
tric terminals on the cable before this test.
Supply voltage should be present across these ter-
minals when there is a demand for heat.
Set the tester to VAC
20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105110
The resistance of the temperature probe depends on
its temperature (18 000 ohm at 10° C).
See the diagram for proper electric resistance at other
temperatures. Set tester to ohm.
Disconnect the cable from the temperature probe to
the electronic regulation p.c.b. at both ends and
measure the resistance between the two wires in the
cable, which should be infinity. Set tester to ohm
Supply voltage should be indicated when power is
supplied to the
full sequence control p.c.b.
Set the tester to VAC
.
° C
.
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