Shizuoka Seiki VAL6 MPX Series, Service Manual

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Phenomenon Possible Cause How to check Result Remedy
1
．
The heater does
not start.
The lamp does not
light on.
No power source supplied Measure voltage of AC outlet.
Standard:
MPX5 - AC120V
MPX1 - AC230V
If circuit tester indicates 0V, power
source is disconnected Connect power source
Fuse blowout Take fuse out from fuse box, and then
check each lead with circuit tester If multimeter reads
∞
Ω, fuse blows
out
Find a cause of blown fuse and
replace with a new one
Disconnection of power cable Take power source connector (CN 1)
out from burner controller, and then
check each lead with multimeter If either of the lead is broken, power
cable is broken Make sure the power cable is
connected, or replace it
Loose connection of power
source connector Plug in power source connector (CN
1) again, and then turn on If it works normally, power source
connector fails in contact Plug in connector (CN 1) firmly
Loose connection of transformer
connector Plug in transformer connector (CN 7)
again, and then turn on If it works normally, transformer
connector fails in contact Plug in connector (CN 7) firmly
Failure of transformer Measure voltage at output side of
transformer connector (CN 7) If multimeter reads normal voltage
at input side, and reads 0V at output
side, transformer fails Replace transformer
Standard (purple-purple):
about AC15V
Loose connection of operating
switch connector Plug in operation switch connector
(CN 8) again, and then turn on If it works normally, operation
switch connector fails in contact Plug in connector (CN 8) firmly
Failure of operating switch Take operating switch connector (CN
8) out, and then check lead with If it doesn't conduct when turned on,
operating switch fails Replace operating switch
Standard: Conducting (0Ω) when
turned on
Failure of burner controller Measure voltage at input side of
transformer connector (CN 7)
Standard (white-red):
MPX5 - AC120V
MPX1 - AC230V
If power source is normal and
multimeter reads 0V at input side,
burner controller fails Replace burner controller
Run lamp is lit Loose connection between
thermostat connector and cap Attach the cap firmly If it works normally, the cap fails in
contact with thermostat connector Attach the cap firmly
Misfire lamp is lit.
Flame monitor lens is perplexed
by direct sunlight It starts to operate Avoid direct sunlight on radiation
disk
Failure of burner controller It doesn't start to operate Replace burner controller
VAL6 MPX5/MPX1 Troubleshooting
Unplug flame monitor connector (CN
11), and then start operation
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