AERCO SWDW68 U-Tube Double-Wall Heaters w/ECS - Manual (Page 74)

HE-
111 − CORRECTIVE MAINTENANCE
Rev B Mar 2013 8-20
3. Loosen the terminal wiring connection screws on the rear of the Over-temperature Switch assembly
and disconnect the wires.
4. To remove the Over-temperature Switch assembly, push in tab of each of two side retaining clips
(Figure 8-11b), slide toward rear and remove.
Figure 8-11a. Over-Temperature Switch & Temperature Indicator
Figure 8-11b. Over-Temperature Switch & Temperature Indicator Installation
5. If the replaced unit is an Over-temperature Switch, set the desired over-temperature alarm limit using
the adjustment procedures in Chapter 4, Section 4.3.2.
6. Following adjustment (if necessary), raise and secure the swing-down panel. Close and secure the
Control Box door.
8.3.4 Replacing the DC Power Supply
To replace the DC Power Supply, please refer to Figure 8-11a through 8-12d and proceed as follows:
1. Open the Control Box door and loosen the captive screw on the recessed panel inside the door.
2. Open the swing-down panel and locate the DC Power Supply on the left interior wall of the Control
Box (View A - A).
3. Disconnect the AC input power connector near the bottom of the Power Supply and the DC output
connector near the top.
4. Remove the four hex standoffs and lock washers securing the DC Power Supply to the studs on the
interior side wall of the Control Box. Completely remove the DC Power Supply from the Control Box.
5. Replace the DC Power Supply by reversing the previous steps.
8.3.5 Replacing the DC Voltage Regulator
To replace the DC Voltage Regulator, please refer to Figure 8-11a through 8-12d and proceed as follows:
1. Open the Control Box door and loosen the captive screw on the recessed panel behind the door.
2. Open the swing-down panel and locate the DC Voltage Regulator on the bottom of the chassis
interior (View D – D).
To uninstall, push tab to
release clip retainer. Slide
clip back and off. Remove
assembly through front
panel.