Service manual

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© January 2013 Aqua-Hot
®
600-D01 Series Hydronic Heating System Service Manual - Rev. A
SECTION 4: AQUA-HOT COMPONENTS
This section details various components of the Aqua-Hot
that may require troubleshooting and/or replacement in
the event of a malfunction. The diesel-burner and its
components are detailed in Section 9 of this manual.
Replacement parts can be ordered through Aqua-Hot’s
Web site at www.aquahot.com or by calling 1-800-685-
4298.
If additional assistance is needed, the Technical Support
Team can also be reached, Monday through Friday, from
7:00 AM to 4:00 PM Mountain Standard Time at 1-800-
685-4298.
Fluid-Level Sensor:
The fluid-level sensor monitors the level of antifreeze and
water heating solution within the Aqua-Hot’s boiler tank to
ensure that an adequate volume exists.
Troubleshoot the fluid-level sensor if one of the following
conditions has occurred:

The diesel-burner and/or electric heating element fails to
operate.

The Aqua-Hot fails to operate and the “Low Tank-Level
Cutoff” indicator light on the electronic controller is
illuminated.
Troubleshooting:
1.
Verify that the Aqua-Hot’s boiler tank is full of the anti-
freeze and water heating solution.
2.
Verify that the harness wire connectors are securely
plugged into the fluid-level sensor.
3. Verify that the fluid-level sensor’s wires are securely
installed in the terminal strip on the wire harness, as well
as tightly fastened to the electronic controller.
4.
Verify the functionality of the fluid-level sensor by com-
pleting the following:
A.
Remove the faceplate from the electronic controller.
B.
Install a jumper wire on the JP3 plug, between pins
15 and 16 (between “LWCO-I” and “LWCO-O”) on
the electronic controller in order to bypass the fluid-
level sensor.
If the “Low Tank-Level Cutoff” indicator light on
the electronic controller extinguishes when the
jumper wire is installed, inspect the wire harness for
damaged or severed wires. If no wires are found to
be damaged or severed, follow the instructions in
this section to replace the fluid-level sensor.
If, however, the “Low Tank-Level Cutoff” indicator
light continues to illuminate once the jumper wire is
installed, inspect the JP3 plug for damage. If no
damage is found follow the instructions in this man-
ual to replace the electronic controller.
Replacement Procedure:
FAILURE TO DISCONNECT ALL POWER SUPPLIES AND/OR
TO ALLOW THE HEATER TO COOL BEFORE SERVICING
COULD CAUSE SERIOUS DAMAGE OR PERSONAL INJURY.
1.
Ensure that the Aqua-Hot has been completely shut
down and that all power sources have been disconnect-
ed. Also, because this replacement procedure will
involve the boiler tank and the potential for hot coolant,
be sure the heater has adequately cooled.
2.
Drain the antifreeze and water heating solution from the
Aqua-Hot’s boiler tank using the drain valve, Approxi-
mately 2-3 gallons will need to be drained..
3. Disconnect the Fluid Level Sensor’s wires by separating
the quick-disconnect terminals.
4.
Using a 7/8 socket, remove the defective Fluid Level
Sensor from the Aqua-Hot’s boiler tank.
5.
Wrap the threads of the replacement Fluid Level Sensor
with a thread seal tape.
6.
Screw the replacement Fluid Level Sensor into the port
on the Aqua-Hot’s boiler tank and tighten securely with
a 7/8 socket, ensuring the N.O. stamp in on top.
Be sure to install the replacement float switch with
the “N.O.” stamp on top, failure to do so, will allow
the diesel/electric to come on with no antifreeze in
the boiler tank.