Aqua-Hot Hydronic Heating System Shop Manual 09/04
®
SECTION 7: TROUBLESHOOTING
Section 7.10,
continued
Section 7.10,
continued
I.
Turn the
“Diesel”
switch
ON
and allow the
Aqua-Hot
to reach maximum operating
temperature (i.e., until the
Diesel-Burner
cycles
OFF
). Locate both the
VAC High-
Limit
Thermostat
and the
VAC/VDC Control
Thermostat
and check for continuity;
reference Figure 1.
A:
If there is no continuity at the
VAC
High-Limit Thermostat
, but there is
continuity at the
VAC/VDC Control
Thermostat
:
The
VAC/VDC Control Thermostat
must be replaced. Please contact
the Technical Support Department
at 1-800-685-4298 for assistance.
If there is continuity at the
VAC High-
Limit Thermostat
, but none at the
VAC/VDC Control Thermostat
:
The overheat condition may have
been caused by another faulty
component, and no further
troubleshooting is necessary;
reference “NOTE (7.10-D).”
Please contact the Technical
Support Department at 1-800-
685-4298 for additional
assistance.
NOTE (7.10-D):
If the
VAC High-Limit Thermostat
continues to trip, and no overheating problems were
discovered (i.e., faulty
VAC/VDC Control Thermo-
stat
), it may be that the
VAC High-Limit Thermostat
is not operating properly and may need to be
replaced.
Q3 : Is VAC power being supplied to the
VAC
Relay
?
WARNING:
The following checks
need to be performed with the
motorhome connected to VAC
power. Therefore, be sure to use
extreme caution when performing
each check, as 120 VAC power will
be present at each of the electrical
components. Failure to do so may
result in serious bodily injury
(i.e.,
an electrical shock).
NOTE (7.10-E):
The Temperature of the Aqua-Hot’s
Boiler Tank
must be below 160°F prior to performing
this test.
I.
Turn the
“Electric”
switch
ON
and uncover
the
VAC Relay
located on the reverse side
of the
Thermostat Access Cover
; reference
Figure 1. Check for AC voltage at both
Black (+)
wires (“120 VAC Power Supply”)
connections on the
VAC Relay
; reference
Appendix A. Be sure to utilize the “JP7
GND” stud as a ground source when
performing this AC voltage check.
Is voltage present?
A:
If YES:
Proceed to Q4.
If NO:
1. Check for loose wire connec-
tions at the Motorhome’s VAC
junction box.
2. If the VAC wire connections
are in good condition, please
proceed to step 3.
3. Check the
VAC Relay
to ensure
that it is functioning properly.
NOTE (7.10-F):
Inspect the
VAC Relay
for damage.
If visual signs of damage exist, the
relay
must be
replaced.
I.
Disconnect both
Black VAC wires
from the
VAC Relay terminals
. Activate the
“Electric”
switch
ON
and
OFF
, then check for continu-
ity across the two open
terminals
. Please
note, with the
“Electric”
switch
ON
, continuity
should be present at the relay’s
terminals
.
With the
“Electric”
switch
OFF
, no continuity
should be present.
Is continuity present across the two
terminals
of the
VAC
Relay
?
A:
If YES:
Proceed to Q4.
If NO:
The
VAC Relay
must be replaced.
Please contact the Technical
Support Department at 1-800-
685-4298 for assistance.
!
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