AERCO SmartPlate User Manual
Page 52
SmartPlate Installation, Operation & Maintenance Manual
CHAPTER 7 – TROUBLESHOOTING
Page 52 of 138
AERCO International, Inc.
100 Oritani Dr. Blauvelt, NY 10913
OMM-0069_0E
PRI: 11/26/2013
Phone: 800-526-0288
SP-100
Table 7-2. Troubleshooting – Electronic Control System (ECS/SP) – Cont.
No.
Fault Indication
Probable Cause
Corrective Action
T6
Over-Temp. Alarm
condition cannot be
cleared.
Over-Temp Switch
displays erroneous
temperature readings
1. Shorted Outlet Temp.
Sensor.
2. Defective Over-
Temp. Switch.
3. 3-Way Control Valve
not closing fully
during no-load
conditions.
4. A “No-Flow”
condition caused a
gradual buildup of
heat to the water in
vessel.
5. Heater recirculation
pump shut off or
failed.
1. Replace Outlet Temp, Sensor.
2. Replace Over-Temp Switch.
3. Calibrate 3-Way Control Valve per
paragraph 4.2.1.
4. Open hot water valve at sink or tub outlet
to see if fault clears. If there is no flow
through heater, go to Probable Cause 5.
5. Check recirculation pump to ensure it is
turned on and functioning properly. Also,
check pump fuse on side of Control Box.
T7
Outlet water temp. far
below Setpoint
1. Incorrect Temp
Controller setting
2. Defective Temp.
Controller.
3. Heat Exchanger
fouled on Boiler
Water side.
4. Defective Control
Valve Actuator
5. Boiler water supply
temp. is too low.
6. Boiler Failure
1. Refer to Chapter 4 and check the current
setting of Over-Temp. Switch. Readjust if
necessary.
2. Remove the cover from the Electronics
Module of the Control Valve and verify that
the Temp. Controller is generating a
control signal greater than 0 VDC. If not
replace Temp. Controller.
3. Clean Boiler Water Inlet Strainer.
Clean Heat Exchanger.
4. Replace Valve Actuator (SEE TABLE 7.1)
5. Increase boiler water temperature.
6. Check operational status of Boiler.
T8
Wide fluctuations in outlet
water temperature during
large flow changes.
1. Heater Recirculation
Pump not operating.
2. Boiler water temper-
ature drops below
DHW setpoint during
heavy demand, then
recovers.
3. Boiler water temper-
ature drops below
DHW setpoint but
does not recover until
load is reduced.
4. Boiler water supply
temperature is too
high.
1. Check Control Box fuse and power to
pump.
2. Install Boiler Water Buffer Tank to provide
hot water reservoir for the SmartPlate
Heater to draw from during large load
swings.
3. The boiler water supply is under-sized.
Add more boilers or reduce DHW usage.
4. Control Valve is not seating properly. See
Chapter 4 and auto-stroke valve.