Fluid Circulation Pump
©Aqua-Hot®
250-D03 Diesel Series Service Manual
REV 220302
p. 34
AC Electric System
Introduction:
The AC Electric system of the Aqua-Hot 200 Series unit functions
to provide
supplementary heat to the Aqua-Hot boiler tank.
This is done with an electric element, an electric relay, and a
DC “control circuit” which engages the electric element when
determined necessary by the ETS module and the controller.
The electric heating element is not intended to serve as the
sole heating source of the Aqua-Hot. The AC electric system will
provide enough heat for hand washing and to maintain tank
temperature. Any greater applications require the use of the
diesel burner.
Troubleshooting Condition:
Troubleshoot the AC Electric system if the electric element is
not functioning properly. This can be verified with a simple, but
rather lengthy, test outlined below.
The following conditions must be met before the AC Electric
system can be diagnosed, and if necessary, repaired.
•
The fluid expansion bottle is filled to at least the “COLD”
mark.
• Verify that all in-line fuses are functional.
• Ensure that the unit is completely cool.
• Ensure that DC electrical power is supplied to the Aqua-Hot.
• Ensure that AC electrical power is supplied to the element.
• Verify the thermostats are in working order.
If any of the above conditions are not met, correct them before
continuing with troubleshooting. Results of the troubleshooting
procedure cannot be verified if the conditions listed above are
not fulfilled.
Figure 56
AC Electric System
Verify Functionality:
1. Turn OFF both the electric and the burner on the LCD
screen.
2. Allow the unit to cool completely.
3. Verify that the Aqua-Hot is connected to an AC power source
such as shore power or an AC generator.
4. Using an infrared thermometer take the temperature of
the tank face. The thermometer should be 12” away from
the tank face and set to “high emissivity”. Record this
temperature on a notepad.
5. Move only the electric to ON.
6. Verify that the LCD screen shows electric status as ON.
7. After an hour, take another temperature reading on the
tank face. If the temperature of the tank face has risen, the
electric element is correctly operating.
If through the above procedure it’s been determined that
the electric element is not functioning properly, follow the
instructions below to troubleshoot.
Troubleshooting:
1. Verify the following before troubleshooting the AC Electric
System:
• The ETS module is calling for heat
• The interlock switch is depressed
•
The overflow bottle is adequately filled
• The AC high-limit thermostat is not tripped
• There are not faults on the LCD screen.
2. Locate the LCD screen and navigate to the TESTING page
(Figure 58). Tap ELECTRIC.
• The AC electric relay should let out an audible click
from within the Aqua-Hot cabinet. If no click, verify
the AC electric relay has functionality, and if no
functionality, replace the relay.
• If there is a click sound, leave the ELECTRIC to ON.
Tap PREVIOUS and activate the pump. Allow the
Aqua-Hot to get to 170°F (approximately 1 hour).
• Verify the tank temperature on the screen, on the
DIAG screen (180°F). See Figure 57. If the tank is
not to temperature, check the element for 11.2-13
amps. If there is less than 11 ohms of resistance,
replace the element.
3. Verify that the controller is sending 12V DC power to the AC
relay using a voltmeter. Test wire J6-1 for 12V DC
• If 12V DC is not present while the electric element
is on, and status is ON on the LCD screen, the
controller will need to be replaced.
• If 12V DC power is present at wire J6-1, turn off all
RV-side breakers providing power to the Aqua-Hot,
then disconnect the Molex plug AC connection.
