Watts AERCO SmartPlate SP23 - Page 53

SmartPlate Installation, Operation & Maintenance Manual
CHAPTER 7 – TROUBLESHOOTING
OMM-0069_0H • SP-100 • 1/30/2020 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page 53 of 134
TABLE 7-2. Troubleshooting – Electronic Control System (ECS/SP)
No.
Fault Indication
Probable Cause
Corrective Action
T9
Temperature control not
within specifications.
Items T1 – T8 check out
OK.
Wide fluctuations in
outlet water temperature
under low flow
conditions.
1. Unexpected system
dynamics.
2. Outlet Temp Sensor
connected to Temp
Controller gives
inconsistent or
intermittent
readings.
3. Mixed Water Temp
Sensor is open,
shorted or gives
inconsistent
readings.
4. Recirculation Pump
failure.
1. See Table 7-3 for Temperature Control
Troubleshooting.
2. Replace Outlet Temp Dual Sensor at
the Water Heater outlet port.
3. Replace Mixed Water Temp Sensor.
4. Replace Recirculation Pump
T10
Wide fluctuations in
outlet water temperature
under low flow
conditions.
1. Outlet Temp Sensor
connected to Temp
Controller gives
inconsistent or
intermittent
readings.
2. Mixed Water Temp
Sensor is open,
shorted or gives
inconsistent
readings.
3. Recirculation Pump
failure.
1. Replace Outlet Temp Dual Sensor at
Water Heater outlet port.
2. Replace Mixed Water Temp Sensor.
3. Replace Recirculation Pump
NOTE:
Refer to the Dynamic Temperature Control Settings specified in Table 7-3A when performing
the Corrective Actions listed in Table 7-3 which follows. Adjustment of Pb, Pb2 and FFPb can
be accomplished from the first menu level on the Eurotherm 2408 Controller. Refer to
Chapter 4, section 4.2 for procedure.