Thermostat Removal/Replacement; Element Cleaning/Replacement - A.O. Smith AOSRE50400 Instruction Manual

3. Using a Philips screwdriver, unscrew the bottom screw securing
the outer door, see Figure 8.
4. Lift up and remove front panel.
fiGure 8.
thermostat removal / replacement
R E M O V A L
1. Turn off and unplug the water heater from the electrical outlet.
2. Remove the front panel, see the "REMOVING THE FRONT
PANEL" section in this manual. Remove the insulation pad.
3. Using a 7mm wrench, loosen the nuts securing the high limit switch
to the tank enough to rotate the switch 90° counterclockwise and
slide it out from beneath the bracket. It is not necessary to remove
the nuts completely.
4. Remove the 3 wires (white, brown, and green/yellow) from the
thermostat at the spade connections, carefully taking note of the
original location of each wire.
5. Unscrew the 2 screws securing the thermostat to the front panel
and remove thermostat.
fiGure 9.
REPLACEMENT
1. Place the new thermostat against the front panel and secure
it with the two screws.
2. Reattach the wires at the spade connections, taking care to
place them in their original locations. Be sure to push the
connector completely onto the spade terminals.
3. Secure the temperature sensor to the tank by tightening the
nuts. Be sure the sensor is firmly in contact with the tank
surface.
4. Replace the insulation block and the front panel.
element cleaninG / replacement
To remove the element from the tank in order to clean or replace it:
. Turn off and unplug the water heater from the electrical outlet
and follow "DRAINING INSTRUCTIONS."
2. Remove the front panel, see the "REMOVING THE FRONT
PANEL" section in this manual. Remove the insulation pad.
3. Remove the two screws from the mounting bracket, see Figure
10, being careful not to drop the screws into the unit, as they will
be difficult to retrieve. Remove bracket and set screws aside.
4. Remove the two spade connectors from the element.
5. Using a 10mm wrench, remove the four nuts around the element
flange. Set nuts and lockwashers aside.
6. Lift element up to clear the four mounting bolts, rotate 15° clockwise,
and lift out.
7. Discard the old gasket and clean the area around the element
opening. Remove any sediment from or around the element opening
and inside the tank.
8. If you are cleaning the element you have removed, do so by
scraping or soaking in vinegar or a deliming solution.
note: replacement elements must (1) be the same voltage
and (2) no greater wattage than listed on the model rating plate
affixed to the water heater.
9. A new gasket must be used in all cases to prevent a possible
water leak. Place new element gasket in the element opening
over the four element bolts, orienting the gasket bulge facing
water side.
10. Insert the curved part of the element, rotate 20° clockwise, and
continue to insert the element, being sure that the four bolts fit into
the element flange.
11. Replace the four lockwashers and 10mm nuts. Tighten until snug.
DO NOT OVERTIGHTEN.
12. Place unit back on wall mounting bracket hooks. Reconnect the
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