Fluid Circulation Pump
©Aqua-Hot®
250-D03 Diesel Series Service Manual
REV 220302
p. 53
Burner Components
Diesel Burner Motor
The diesel burner motor drives the combustion air blower and
the fuel pump. In order to perform the following procedures, it
may necessary to detach the diesel burner head.
Troubleshooting Procedure:
1. Locate the diesel burner controller’s C-plug and insert the
probes of a DC voltmeter into the C-2 (+) and the C-5 (-)
locations.
• Turn the burner ON and verify the burner status is ON,
on the LCD screen.
• Observe the voltage level. If a normal voltage range
registers on the voltmeter and the motor is not
operating, inspect the C-plug harness for any loose or
damaged wire connections. If the C-plug harness and
connections are in good condition and the motor is not
in operation, the motor must be replaced.
If there is not 12V DC present on the C-2 pin, continue with
the troubleshooting procedure.
2. Verify the controller is sending power to the diesel burner
motor.
• Using a voltmeter, check for 12V DC on the controller
B-plug pin 4. If no power, verify the controller is
receiving power from the batteries.
Figure 85
NOTE:
The Aqua-Hot 200 Series is equipped with a 20A Fast
Blow Fuse, located on the J2-12 wire, between the Aqua-Hot
main plug and diesel burner controller’s B-plug. Reference
Figure 86.
Figure 83
• Using a voltmeter, check for 12V DC on the controller
at shown below.
• If no power is present, verify there are no faults
showing. If no wire damage or faults, the controller
will have to be replaced.
Figure 87
Figure 86
Diesel Burner Controller
Figure 84
Burner 20A
Fast Blow
Fuse
Burner Power (+)
ACCESS COVER
INTERLOCK SWITCH
BURNER
CONTROLLER
AQUA-HOT
CONTROLLER
NOTE:
The motor may have a flat spot and will cause the
burner to work intermittently. When testing the motor, be
sure to test it multiple times to find the intermittent problem.
