Electric Heating Element - Aqua-Hot 375-d Service Manual

Electrical - AC

Electric Heating Element:

The electric heating element uses AC power as an alternate
power source for heating the Aqua-Hot's boiler tank.
Troubleshoot the electric heating element if the following
condition has occurred:

There is a lack of hot domestic water and interior heat
when the electric element is selected as the heating
source.
Troubleshooting:
NOTE: For continuous domestic hot water to be present, the
diesel-burner must be selected also as a heating
source.
1. Verify that the motorhome is either plugged into shore
power or that the generator is running to provide AC
power.
2. Verify that the "Electric" Switch is on, inside the motor
home.
3. Using a Volt Meter, Verify the presence of 12vdc volt
age at the terminal block on both the AI (power in from
switch) and AO (power out to switch) pins.
If there is no 12VDC voltage present, complete the fol-
lowing:
A. Verify that the electric element switch on the interi-
or switch panel is on.
B. Verify heater is full of antifreeze, if the heater is full
of antifreeze, trouble shoot Float Switch
C. Install a jumper wire on the terminal block, between
the AI and AO pins to bypass the electric element
switch.
If the "Electric Heating Element " works with the
jumper wire installed, replace switch.
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© 2009 Aqua-Hot 375D Hydronic Heating System Service Manual—Rev. A
S 4: A
ECTION
If the Electric Switch is on, and operating properly:
A. Check the temperature of the Aqua-Hot's boiler
tank.
If the boiler tank temperature is below 158°F, trou-
bleshoot the control thermostat for the electric ele-
ment.
If the boiler tank is above 185°F, the Aqua-Hot is at
operating temperature and requires no heat.
4. Check functionality of the A.C. Relay. Refer to A.C.
Relay troubleshooting, in this section.
5. Verify that the electric heating element is receiving ade-
quate AC power by completing the following:
A. Remove the AC access cover.
B. Using an AC voltmeter, verify that 110 volts of AC
power are present.
C. Using an amp-meter, verify that 11.2 to 13 amps are
present at the element's wires.
D. Disconnect the coach from shore power/turn off
generator and Check the electric element's wires for
continuity by completing the following:
a. Disconnect the wires from the electric heating
element.
b. Disconnect the wires from the AC terminal
block.
c. Check the black and white wires at the terminal
block for continuity.
5. Check the electric heating element for functionality by
completing the following:
A. Disconnect all power supplies.
B. Remove all wires from the electric heating element.
C. Using an ohmmeter, check the electric heating ele-
ment for continuity.
-H C
QUA OT OMPONENTS
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