AERCO Electronic Controls System (ECS) - Manual (Page 44)

Electronic Control System (ECS) and Type CXT-E Valve
7. TROUBLESHOOTING
Page 44 of 82
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, New York 10913 • Phone: 800-526-0288 VD2: 02/28/14
OMM-0003_0D AC-105
Table 7-2. Troubleshooting – Electronic Control System (ECS)
NO. FAULT INDICATION
PROBABLE
CAUSE
CORRECTIVE ACTION
T6
System not operating.
All displays are blank.
1. External 120
VAC power
disconnected.
2. Defective
ON/OFF switch
on Control Box.
3. Defective DC
Power Supply.
1. Ensure external circuit breaker is ON. Check
for 120 VAC power across TB-2 terminal
leads 101 (Line) and 102 (Neutral).
2. Set ON/OFF POWER switch to the ON (Up)
position and verify that the switch indicator
lights. Also:
a. Verify that 120 VAC is present across TB-2
terminal leads 100 (Line) and 102 (Neutral).
b. If voltage not present, replace ON/OFF
POWER switch.
3. Disconnect the DC output connector on the
left internal wall of the Control Box (Figure 8-
9, sh. 2). Verify that 24 VDC is present across
the V+ and V- terminals.
If 24 VDC not present, replace the DC Power
Supply.
T7
Water Heater outlet
temp. consistently
above Setpoint by 10°F
or more.
However, temperature
is below Over-Temp.
limit setting.
1. Temp. Controller
is not properly
set.
2. Faulty Temp.
Sensor
(thermocouple) is
connected to
Temp. Controller.
3. Valve Actuator
not properly
secured to
Linkage
Assembly.
1. Refer to Section 3 – ADJUSTMENTS and
check current setting of Temp. Controller.
Readjust if necessary.
2. Verify Outlet Temp Sensor is securely
connected to cable plug. Replace the Dual
Sensor if necessary.
3. Check to ensure that the Actuator is
securely fastened to the Linkage Assembly.
Tighten if needed and readjust the CXT-E
Control Valve per Section 3.
T8
Over-Temp Alarm
occurs repeatedly.
NOTE
Audible alarms will be
generated if Outlet
Temp Sensor is open.
Erroneous temperature
readings will be
displayed if Sensor is
shorted.
1. Over-Temp Switch
not properly set.
2. Open or shorted
Outlet Temp.
Sensor
(thermocouple)
connected to
Over-Temp.
Switch.
3. Over-Temp Switch
is defective.
1. Refer to Section 3 and check the current
setting of the ECS Over-Temp. Switch.
Readjust if necessary.
2. Check thermocouple connections between
Sensor connector plug and TB-1 terminal
leads 111 (+) and 112 (-). If connections are
secure, replace Dual Temp Sensor.
3. Replace Over-Temp Switch.