Shizuoka Seiki VAL6 MPX Series, Service Manual

Page: 10 / 23

Phenomenon Possible Cause How to check Result Remedy
VAL6 MPX5/MPX1 Troubleshooting
Misfire lamp is lit.
Absorbing air into fuel lines
from joints Check looseness of each joint If any joint is loose, air is absorbed
into fuel lines from loose joint Fasten joints more tightly
Insufficient pumping of fuel
because vacuum forms in fuel
tank Check if air intake of tank cap is
clogged with dust If air intake of tank cap is clogged,
fuel flow is insufficient by vacuum
forming in fuel tank Clean air intake of tank cap
Shortage of light detected by
flame monitor Take flame monitor out, and then
check clarity of its lens If lens of flame monitor is dirty, it
detects a little light Wipe lens of flame monitor with
soft cloth
Remove burner, and then check clarity
of burner cone and vane If burner cone or whirl vane is dirty,
flame monitor detects a little of light Clean burner cone and whirl vane
Flame monitor connector is
loose connection Plug flame monitor connector (CN
11) again, and then turn on If it works normally, flame monitor
connector fails on contact Plug connector (CN 11) firmly
Failure of flame monitor Unplug flame monitor connector (CN
11), and then check transition of
resistance by changing quantity of
light into flame monitor If resistance doesn't change, flame
monitor fails Replace flame monitor
Nozzle clogged Replace nozzle If it works normally, nozzle was
clogged Replace nozzle
Filter element clogged Check clarity of filter element If filter is dirty, fuel flow decreases
because of clogged filter element Clean or replace the filter element
5
．
Smell of fuel comes
out.
Quantity of combustion air is
too much Check gate opening of combustion air
inlet If opening is too extensive, it burns
imperfectly Decrease gate opening of
combustion air inlet.
Normal scale:
MPX5 - 2.5
MPX1 - 4.5
Nozzle clogged Replace nozzle If it works normally, nozzle is
clogged Replace nozzle
Filter element clogged Check clarity of filter element If filter is dirty, fuel flow decreases
because of clogged filter element Clean or replace the filter element
Incorrect nozzle Check makers imprint of the nozzle if
it is correct.
Mark: 0.4USgal/h 80° H If makers imprint is incorrect, the
nozzle is incorrect Replace incorrect nozzle for
correct one
4
．
Combustion stops
during operation.
10