AERCO SmartPlate User Manual
Page 85

SmartPlate Installation, Operation & Maintenance Manual
CHAPTER 8 – CORRECTIVE MAINTENANCE
OMM-0069_0E
AERCO International, Inc.
100 Oritani Dr. Blauvelt, NY 10913
Page 85 of 138
SP-100
Phone: 800-526-0288
PRI: 11/26/2013
SECTION IV SMARTPLATE ELECTRONIC CONTROL SYSTEM (ECS/SP)
WARNING
TURN OFF THE CONTROL BOX POWER SWITCH AND
DISCONNECT AC POWER PRIOR TO PERFORMING ANY
CORRECTIVE MAINTENANCE PROCEDURES IN THE
FOLLOWING PARAGRAPHS. FAILURE TO OBSERVE THIS
WARNING MAY RESULT IN SERIOUS PERSONAL INJURY.
8.13 ECS/SP CONTROL BOX ASSEMBLY AND COMPONENTS
Corrective maintenance for the Control Box and internally-mounted components consist of
removing and replacing the following items:
Control Box Assembly
Temperature Controller
Over-Temperature Switch
Temperature Indicators
24 VAC Step-Down Transformer
The following paragraphs reference Figures in previous Chapters as well as Figures in this
Chapter. Refer to the applicable Figures as necessary when performing the replacement
procedures which follow.
8.14 CONTROL BOX ASSEMBLY REPLACEMENT
If necessary, the complete ECS/SP Control Box Assembly can be removed and replaced as
follows:
1. Loosen the captive screws on the Control Box door and the recessed panel (Figures 2-3,
2-4).
2. Open the swing-down recessed panel. Locate and disconnect the Line, Neutral and
Ground leads connected to Terminal Block TB-2 on the bottom interior surface of the
Control Box chassis (Figure 2-5).
3. Refer to Figures 1-1 and 1-2 and disconnect the Control Box cables from the following
devices:
a) Disconnect Control Valve (Siemens MXG-461) power and signal leads from terminal
strip TB-1.
b) Disconnect the external AC power leads from terminal strip TB-2.
c) Disconnect the Recirculation Pump power leads from terminal strip TB-2.
d) Disconnect the Mixed Inlet Temp cable from the Mixed Inlet Temp Sensor on the top
of the Manifold of the Water Heater.
e) Disconnect the Hot Water Outlet Temp cable from the Dual Outlet Temp Sensor at
the DHW outlet of the Water Heater.
f) Disconnect BOILER TC IN and TC OUT leads (2-pin Molex connectors) connected to
the heating fluid (boiler water) inlet and outlet Temperature Sensors.