AERCO ECS Retrofit - Manual (Page 19)

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2.6 Control Box Removal
The existing Control Box (Figure 2-1) is secured to the Heat Exchanger using a special mounting
bracket. The top end of this mounting bracket contains a slotted cutout which is inserted around one
of the studs securing the top head to the shell flange. A hex nut secures the bracket in place. The
currently installed Control Box will no longer be used. However, the mounting bracket will be reused to
mount the new ECS Control Box. Remove the Control Box and mounting bracket assemblies as
follows:
1. Check to ensure that the external power source has been turned off.
2. Disconnect all power supply wiring to the Control Box. Also, disconnect all wiring between the
Control Box and any external Solenoid Valves.
3. If a Pneumatic Control Valve Actuator is currently installed on the Heater, disconnect the air
supply and control air tubing from the Control Box.
4. Disconnect the Pressure Gauge compression fittings.
5. Cut all wire ties leading to the Control Box. Do not cut the thermal element.
6. Loosen, but do not remove, the hex nut securing the Control Box Mounting Bracket to the Top
Head stud (Figure 2-9).
7. Completely remove the Control Box and Mounting Bracket from the Water Heater.
8. Open the Control Box door. From the rear of the Control Box, remove the six 8-32 screws
securing the Rear Mounting Panel to the enclosure (Figure 2-10).
9. Remove the Rear Mounting Panel from the Control Box to access the two screws securing the
Mounting Bracket to the Box
IMPORTANT
Save the Control Box Mounting Bracket when it is removed from the Control
Box. This Mounting Bracket will be used to install the new ECS Control Box.
10. Remove the two screws securing the Mounting Bracket to the Control Box. Separate the
Control Box and Mounting Bracket. This Control Box will no longer be used and can be
discarded. However, the Mounting Bracket will be reused to attach the new ECS Control Box
to the Heater in Section 4.