Phenomenon
Possible Cause
How to check
Result
Remedy
VAL6 MPX5/MPX1 Troubleshooting
6
．
Smoke comes out.
Shortage of combustion air
Check extent of combustion air inlet
opening
If combustion air inlet is too small,
it burns in short of Oxygen
Extend combustion air inlet
opening.
Normal scale:
MPX5 - 2.5
MPX1 - 4.5
Decrease of airflow from fan
motor
Check if fan is dusty
If fan is dusty, it is short of air
Clean fan
Decrease revolutions of the fan
motor
Measure voltage at power source
connector
If voltage at power source is lower
than standard, combustion air is
decreased because of low voltage
Check voltage
(Power source voltage is
insufficient)
Standard:
MPX5 - AC120V
MPX1 - AC230V
Nozzle clogged
Replace nozzle
If it works normally, nozzle was
clogged
Replace nozzle
Using at high altitude area (Low
oxygen concentration)
Know the altitude if using at lower
than the altitude of 1000m(3000ft)
If using at higher than the altitude of
1000m(3000ft), heater burns
imperfectly because of shortage of
oxygen
Extend combustion air inlet
opening.
Normal scale:
MPX5 - 2.5
MPX1 - 4.5
Incorrect nozzle
Check makers imprint of the nozzle if
it is correct.
Mark: 0.4USgal/h 80° H(danfoss)
If makers imprint is incorrect, the
nozzle is incorrect
Replace incorrect nozzle for
correct one
7
．
Combustion is not
stable.
Loose joints in fuel line
Check looseness of each joint
If any joints are loose, air is
absorbed into fuel lines from loose
joint
Fasten joints more tightly
8
．
Fuel leaks.
Loose joints in fuel line
Check looseness of each joint
If any joint is loose, fuel is leaking
Fasten joints more tightly
Failure of drain packing
Remove drain bolt after removing fuel
from fuel tank, and then check
whether packing isn't corrupted
Fuel leaks because of breach of
packing
Replace drain packing
Quantity of fuel in the fuel tank
is too much
Check the fuel level
Fuel overflows because quantity of
fuel in the fuel tank is too much
Decrease quantity of fuel in fuel
tank
11
