Troubleshooting Guide; General Information; Electronic Diagnosis - Aqua-Hot 400 Series Use & Care Manual

General Information

Should the Aqua-Hot Hydronic Heating System fail to
operate, complete the following checks:
1. Verify that the Aqua-Hot's access cover is securely in-
stalled. Reference page 7 (part #4). The Aqua-Hot Hy-
dronic Heating System will not operate if the access
cover is not fully installed.
2. Ensure that the vehicle's fuel tank contains a sufficient
level of fuel. The Aqua-Hot system will not operate if
the fuel level is at or below 1/4 tank.
3. Ensure that the Aqua-Hot's boiler tank has an ade-
quate supply of antifreeze and water heating solution
by checking the level at the Expansion Tank. If the level
is low, reference the Care & Maintenance section of
this guide for refilling instructions.
4. Check the Aqua-Hot's electronic controller for any RED
lights indicating a fault condition.
If the Aqua-Hot Heating System's failure to operate is
not resolved with the aforementioned checks, please con-
tact the Aqua-Hot Heating Systems Technical Support De-
partment at 1-800-685-4298 for additional assistance or
visit the web site at www.aquahot.com.
If the Aqua-Hot's diesel-burner switch "Indicator Light"
does not illuminate and the diesel-burner is not functioning,
locate the electronic controller and check the following:
1. Check the Aqua-Hot's electronic controller for any RED
lights indicating a fault condition. Reference Figure 2.
2. Check for loose wire connections on the electric con-
troller's terminal strips/plugs. When checking for loose
terminal strips/plugs, remove the electronic controller
faceplate by unscrewing the four cover screws.
3. Remove the Aqua-Hot's access cover and check for
loose plug connections on the diesel-burner controller
unit. Reference page 7 (part #4).
NOTE: An interlock switch prevents the Aqua-Hot from op-
erating when the cover is not installed and properly in
place.
4. Ensure the vehicle's fuel tank has a sufficient level of
fuel.
5. If the Aqua-Hot still fails to operate, please contact the
Aqua-Hot Heating Systems Technical Support Depart-
ment at 1-800-685-4298 or visit the web site at
www.aquahot.com.

Troubleshooting Guide

Electronic Controller Diagnosis
Low Tank-Level Cutoff Indicator Light:
This indicator light will illuminate RED when either the
120 Volt-AC electric heating element and/or diesel-burner
have automatically shut down due to low antifreeze and
water heating solution level inside the Aqua-Hot's boiler
tank. This fault will automatically reset when the low level
condition is corrected.
Low Battery Voltage Fault Indicator Light:
This indicator light will illuminate RED and the diesel-
burner will shut down whenever the 12 Volt-DC voltage
level is too low for the Aqua-Hot to operate properly. This
fault must be manually reset after the voltage level has
been restored to the 12 Volt-DC battery system. Reference
"Low Voltage Fault Indicator Light and Reset Button" infor-
mation below.
Low Voltage Fault Indicator Light and Reset Button:
The Aqua-Hot's electronic controller must be manually
reset whenever the low battery voltage fault indicator light
has been activated.
The electric controller can be reset by turning OFF the
diesel-burner switch on the interior switch panel for ap-
proximately 60 seconds, then turning the switch back ON
by pressing the "Low Voltage Reset" button located on the
electric controller (use a thin, straight, non-metallic object
to access the reset button through the small hole on the
faceplate).
Overload Fault Indicator Light:
This indicator light will illuminate RED whenever one of
the following conditions have occurred:
1. The Aqua-Hot is off due to an electrical overload (i.e.,
short) in the main 12 Volt-DC power supply circuitry.
2. The Aqua-Hot is off due to a combination of high elec-
trical 12 Volt-DC power loads and a high surface tem-
perature of the electronic controller.
The Aqua-Hot will automatically restart once the elec-
toral overload (i.e., short) and/or high-heat condition is
corrected.
450-D Use & Care Guide
Aqua-Hot®
15
p.