Result
Cause
Remedy
How to check
Phenomenon
4
lens of flame monitor is dirty
Lock of light quantity to flame
monitor
Clean flame monitor lens
Plug connector (CN 9) firmly
Display「A1」
The value is higher than DC 5V
Failure of burner controller
Replace burner controller
Nozzle is clogged
Flow rate is lower by clogged
Replace nozzle
Make sure that the filter element is dirty ⇒ Figure7(P.19)
Filter element is dirty
Filter element is clogged
Replace filter element
Check air inlet opening of fan moter
Air inlet opening is unusual
Operate with appropriate air inlet opening
Failure of burner controller.
Replace burner controller
5 Combustion stop during the operation.
Check the fuel ⇒ Figure 8(P.19)
Use fuel except diesel and kerosene
Low quality fuel
Operate with appropriate fuel
A. Display「A1」
Be mixed with water
Diesel and kerosenel goes bad
Check air inlet opening of fan moter
Air inlet opening is unusual.
Operate with appropriate air inlet opening
lens of flame monitor is dirty.
Lock of light quantity to flame
monitor
Clean flame monitor lens
Check looseness of each joints
The connection has become loose.
Air is coming
Fasten joints more tightly
B.
Refuel and operate the heater
It works normally.
No fuel in the fuel tank.
Refuel
Failure of fuel sensor
Replace fuel sensor
Replace fuel sensor cord
Standard: black-black : Conducting (0Ω) with fuel
Failure of burner controller
Replace burner controller
C. Display「A3」
Check the ambient temperature
Operate in lower than 30℃（86°F)
Failure of overheat protection
Replace overheat protection
Disconnection of overheat
protection cord.
Replace overheat protection cord
Lack of burner packing
Add burner packing
Deterioration of burner packing
Replace burner packing
D.
Failure of tip-over detector
Replace tip-over switch
※Tip-over detector operation
Disconnection of tip-over
detector connector
Replace tip-over switch cord
Disconnection of tip-over connector
Plug connector (CN11) firmly
Ambient temperature is too
high
Failure of flame monitor
※ Ignition not detected during
operation
It does not conduct when operation
switch is turned on(∞Ω)
(Overheat protection is detected)
Confirmation of burner packing ⇒ Figure15 (P.23)
Display「A4」
Plug connector (CN11) firmly
It does not conduct in horizontal(∞
Ω)
「A3」is not displayed
(A ambient temperature is displayed)
Replace flame monitor
Check if the nozzle is clogged
Improper quantity of
combustion air
Improper quantity of
combustion air
※When it does not correspond to the above content
standard: 3.0 ⇒ Figure 13 (P.22)
light：DC 5V or lower
standard: 3.0 ⇒ Figure 13 (P.22)
The valves does not change or it is
much different from the standard.
standard: dark：DC 5V or higher ⇒ Figure4(P.17)
Replug overheat protection connector (CN 11) , and
then turn on
※Overheat protector operation.
※Ignition not detected during
operation.
Replug tip-over detector connector (CN 11), and then
check conduction with multimeter
Standard: black-black : Conduction(0Ω) when turned
on.
「A1」is not displayed
(A ambient temperature is displayed)
Disconnection of flame
monitor connector
Unplug overheat protection connector (CN 11), and
then check conduction with multimeter
It does not conduct when operation
switch is turned on(∞Ω)
(Overheat protection is not detected)
Misfire within 40 seconds after
ignition.
Standard: red-red : Conduction(0Ω) ⇒ Figure3
(P.17)
Check dirty of flame monitor lens ⇒ Figure11(P.21)
Check dirty of flame monitor lens ⇒ Figure11(P.21)
Display「A2」
※When it does not correspond to the above content
Check voltage of flame monitor
Replug in the flame monitor connector (CN 9) , and
then turn on
Standard: Lower than 30℃(86゜F)
Pour the fuel in the fuel tank about a one-third and,
unplug fuel sensor connector (CN10), and then check
conduction with multimeter
Disconnection of operation
fuel sensor cord
More than 30℃（86°F）
If the multimeter reads ∞ Ω,
Disconnection of overheat
protection connector.
11
