Service manual

— Page 41 —
© January 2013 Aqua-Hot
®
600-D01 Series Hydronic Heating System Service Manual - Rev. A
SECTION 4: AQUA-HOT COMPONENTS
AC Relay: Right
The AC relay is an electrical device where the DC circuit
from the electronic controller determines whether the AC
power is permitted to flow to the electric heating element.
This allows the electronic controller to switch the electric
heating element on and off in conjunction with the interior
switch panel and control thermostat even though the electric
heating element is on a separate circuit.
Troubleshoot the Right AC relay if the following condition
has occurred:

The Right electric heating element fails to operate.
Troubleshooting:
1.
Disconnect the AC power source to the motor home
(unplugging from shore power or shutting off the gener-
ator).
2.
Turn the electric element switch on the interior switch
panel on and check the electronic controller to ensure
that the “Electric Heating Element Status” and the
“Heating Status” indicator lights are illuminated.
3.
Using a voltmeter, check pins 11 and 12 (“AC Relay +”
and “AC Relay-”) on the JP3 plug for 12 Volts-DC.
If 12 Volts of DC power are not present while the
“Electric Heating Element Status” and “Heating Status”
indicator lights on the electronic controller are illuminat-
ed, follow the instructions in this manual to replace the
electronic controller.
If 12 Volts of DC power are present, complete the fol-
lowing:
A.
Locate the AC wires connected to the AC relay
(pins 2 and 4), and remove the AC wires from the
relay.
B.
Using an ohmmeter, check the relay AC pins (2 and
4) for continuity.
If no continuity exists, follow the instructions in this
section to replace the AC relay.
Replacement Procedure:
FAILURE TO DISCONNECT ALL POWER SUPPLIES AND/OR
TO ALLOW THE HEATER TO COOL BEFORE SERVICING
COULD CAUSE SERIUOS DAMAGE OR PERSONAL INJURY.
1.
Ensure that the Aqua-Hot has been completely shut
down and that all power sources have been disconnect-
ed.
2.
Also, ensure that the motor home is not connected to
shore power and that a generator is not connected during
this replacement procedure.
3.
Remove the Thermostat Access Cover.
4.
Release the wires from the defective AC relay by re
moving the corresponding screw terminals.
5.
Remove the defective relay by drilling the rivets that
hold the defective relay in place.
6.
Rivet the replacement AC relay to the AC access cover.
7.
Using the wiring diagram in Appendix A, connect the
wires previously removed to the replacement AC relay.
8.
Reinstall the Thermostat Access cover.