Interlock Switch - Aqua-Hot 400 Series Service Manual

This section of the Service Manual details various compo-
nents of the Aqua-Hot that may require troubleshooting
and/or replacement in the event of malfunction. The Pro-
pane-burner and its components are detailed in Propane
Burner Section of this manual, starting on page 43.
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 be reach at 1-800-685-4298, Monday through
Friday from 7 a.m. to 4 p.m.
Sensors and Switches

Interlock Switch:

The interlock switch is a safety device designed to ensure
that the Aqua-Hot's access cover is securely installed before
the Propane-burner will operate.
Troubleshoot the interlock switch if the following conditions
occur:

The Propane-burner fails to operate.

The Propane-burner switch light does not illuminate.
Troubleshooting:
1. Turn the Propane-burner switch on from the interior
switch panel and ensure that the boiler tank has suffi-
ciently cooled in order to require heat from the Propane-
burner.
2. Verify that the "Heating Status" and Propane-Burner
Status" indicator lights are illuminated green, on the
electronic controller.
3. Disconnect the two yellow wires from the interlock
switch noting the wire #24 is connected to the terminal
labeled "NO" and wire #25 is connected to the terminal
labeled "COM".
4. Using an ohmmeter, check the interlock switch for con-
tinuity while the button is pushed in.
5. If continuity is not present with the button pushed in,
follow the instructions in this section to replace the in-
terlock switch.
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. Disconnect the interlock switch's wires by pulling the
quick connectors from the switch's spade terminals.
2. Release the interlock switch from the Aqua-Hot cabinet
by pushing in on the locking tabs and pulling the inter-
lock switch.
3. Remove the defective interlock switch from the Aqua-
Hot.
4. Install the replacement interlock switch onto the Aqua-
Hot ensuring that the locking tabs snap into place.
5. Connect the Aqua-Hot's replacement wires to the re-
placement interlock switch with yellow wire #24 con-
nect to the terminal labeled "NO" and yellow wires #25
connected to the terminal labeled "COM".
NOTE: If the interlock switch's wires are reversed, the inter-
lock switch will only allow the Propane-burner to operate
when the access cover is removed and the button switch is
released.
Figure 8
© Aqua-Hot® AHE-400-P01 Service Manual Rev.B June 2014
Section #: Title
Aqua-Hot Components
p.
17