MODEL NUMBER (D8L etc.)

SERIES NUMBER (251470GM etc.)

SERIAL NUMBER

USAGE (LIVE ABOARD etc.)

AGE (& TOTAL HOURS if equipped)

PREVIOUS SERVICE DATE'S

AGE OF DIESEL FUEL

1. What does the heater do when the switch (thermostat) is turned on?
    (Example - fan runs - glow plug operates - fuel metering pump is ticking - color of exhaust smoke)

2. If the heater turns off automatically, how many minutes (or seconds) does it take?

3. If the heater turns off automatically, does any of the following occur?
    A. Exhaust smoke _______, Color _______,
    B. Is the fuel pump ticking? _______,
        Is The ticking normal or louder than normal? _______
   C. Is the glow plug getting hot? ______,
   D. Does the heater fan sound normal? ______

4. If the heater ignites, how many seconds does it take, from the moment you turn on the heater until the glow plug turns off?

5. If the heater ignites. Does the heater smoke? ______.
If yes how long does it take for the smoking to clear ? _______

6. How long does the heaters blower continue to run after you turn the heater off?.

7. During the cool down period, does the heater smoke heavily out the exhaust?

8. After the heater shuts down, does the heater smoke out of the combustion air intake?

9. Other clues.

WHAT IS MISSING ?

NO FUEL

= NO SMOKE

LOW FUEL

= WHITE SMOKE

= LOW CO2

HIGH AIR to FUEL

HIGH FUEL

= DARK SMOKE

= HIGH CO2

LOW AIR to FUEL

Heater does nothing.

1. Check & verify that there is power at the heater with a voltmeter or test light.  Check fuses and for loose or corroded connections.

2. Make sure that all switches & thermostats are on.

3. Check to make sure there is power coming back from thermostat.

4. Some models do nothing if the glow plug is "open" or disconnected.

5. Some models do nothing if the fuel metering pump circuit is "open" or disconnected. (Overheat fuse is in this circuit also)

6. Some models do nothing if the motor fuse in the controller is open or motor is defective. (such as the older D4L, D7L and D12L Models)

7. Defective control box

Heater runs 5 sec. - then stops

1. Open overheat sensor (safety thermal cutout switch) or blown overheat fuse

2. Open glow plug circuit

3. Defective control box

Heater runs 16-30 seconds & stops

1. Low voltage at heater control box power input terminals. Check batteries and all connections, fuses or breakers etc.

Note: All voltage tests must be taken when heater is in the start mode with the glow plug operating.

Tries to Ignite for 3 min.

1. Check the glow plug and its electrical connections.

2. Measure the voltage at the heater while glow plug is operating.

3. Measure the voltage at the glow plug/pin while the plug is operating.

4. Check the fuel filters).

5. Is the fuel metering pump "ticking" (check overheat fuse) Check for defective pulse source.

6. Disconnect fuel line at heater, is there fuel coming out?

7. Is the exhaust pipe obstructed ? Is drain coil open ?

8. Is the combustion air intake hose damaged & restricting the combustion air?

9. Is the motor running slow ?

10. Is the combustion air solenoid operating (Older D4L, D7L and D12L)

11.

If this heater has been is severe service, such as live aboard or used as primary dock side heat, or has been installed for 2 to 3 years, the heater may require a "burner service".

Heater ignites, but shuts off at 3 minutes.

1. Check the heater temperature switch (thermo-switch). Note some models the switch is normally open & some are normally closed.

2. Note: many of the newer models use 2 - 90 second start attempts with a purge period in between, this will result in a longer than 3 minute attempt to start. For these heaters the symptom is that the heater shuts off after the second attempt to start.

Heater fan runs, no glow plug or fuel.

1. Check the heater temperature switch (thermo-switch). It may be in the "hot" position - Heater is still in cool down.

2. Defective control box

Ignites & runs OK, but stops before thermostat switches off

1. Check the fuel filters.

2. Check fuel pumps).

3. Clean the thermostat contacts (excludes electronic thermostats).

4. Check for loose wiring connections.

5. Check for high voltage. Measure voltage when it shuts off.

6. Check for low voltage. Measure voltage when it shuts off.

7. Is this a problem only when the engine in running?

Ignites & runs normal, - excessive smoking starting and stopping

1. Normally a symptom of clogged or partially clogged atomizer in models D3L, D7L, D12L AND D12W. Clean or replace atomizer.

2. Other models may require burner service to remove any carbon deposits.

3. White smoke = unburned fuel.

Heater runs OK, Blower runs over 3-4 min. on cool down

1. Check temperature switch (thermo-switch)

2. Sticking relay in control box.

Glow plug is failing more often than normal

1. Check glow plug voltage regulator, if equipped.

2. Check glow plug electrical connections.

3. Check & clean glow plug socket, clean or replace glow plug socket screen.

4. Burner may require service.

5. Check fuel filters & fuel flow.

6. Check burner efficiency by measuring CO2 and exhaust smoke content.

7. Glow plug voltage too high or too low.

8. If coil is collapsed but clean, look for loose elect connections, fuel filters (low fuel), high or low voltage.

9. If plug has excessive carbon buildup, look for a dirty burner, dirty glow plug socket and - or screen, proper fuel quantity and measure CO2

10. Check air supply to glow plug for blockage.

11. Make sure glow plug is tightened enough to seal completely

Heater operates OK, but fuse or breakers blow for no apparent cause

1. Over heat fuse or breaker. Make sure there has been no damage to the ducting, too many registers closed, something sucked into the intake. Measure air temperature out of the heater (at 18" from discharge)

2. Main power or motor fuse. Inspect the fuse holder, if there is any corrosion or signs of heating, replace the fuse holder.
Use only approved fuse holders.

Heater smokes all the time.

1. Verify the motor rpm, it may be too slow.

2. Verify that the exhaust does not have any restrictions. If there is a deposit build up inside the pipe, it requires cleaning.

3. Measure the fuel quantity, it may be too high.

4. Measure the burner efficiency (CO2)