A.O. Smith CAWH 8-455-12, Installation, User And Service Manual

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5. Remove the lowest heating element:
a)
Loosen electrical wires earth (A) and live (L) on the element.
b) Loosen the element (2).
c) Take the element out of the water heater (3).
Carefully store the element.
6. Inspect the tank on limescale through the opening.
7. When there is limescale:
Use a descaling agent to remove the scale and contamination. Contact the supplier of
your water heater for advice on what descaling agent to use.
8. Clean the heating element.
9. Install the heating element:
a)
Place a new gasket (4).
b) Place the element in the tank (3).
c) Tighten the element (2).
d) Attach the electrical wires earth (A) and live (L) on the element.
10. Install the element cover (1).
11. Install the service cover.
12. Install the left side plate of the water heater.
13. Fill the water heater (see 8.7.1).
Fig. Remove a heating element
10.3 Performance check
Make sure that the resistance value of each element is correct:
1.
Remove the left side plate.
Warning
Live cables inside! Switch off the power supply completely (on local isolator) before
removing the left side plate to access the electrical components.
2. Remove the service cover.
3. Measure the resistance value between the two connections of each heating element.
The value needs to be approximately 15,5 +/- 2 Ohm for 3 kW elements, 11 +/- 1,5
Ohm for 4,3 kW elements and 8 +/- 1 Ohm for 6 kW elements.
4. Replace the heating element when the resistance value is not correct.
a)
Decommission the water heater (see 8.8).
b) Loosen electrical wires earth (A) and live (L) on the element.
c) Loosen the element.
d) Take the element out of the water heater.
e) Place a new gasket (4).
f) Place a new element in the tank.
g) Tighten the element.
h) Attach the electrical wires earth (A) and live (L) on the element.
5. Make sure that all wiring is installed correctly.
6. Make sure that all electrical screw connections are tightened.
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