A.O. Smith DRE PLUS, Installation, User And Service Manual

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4. Remove the lowest heating element:
a)
Loosen electrical wires earth (A) and live (L) on the element.
b) Loosen the heating element.
c) Take the heating element out of the water heater.
Carefully store the heating element.
5. Inspect the tank on limescale through the opening.
6. When there is lime scale:
a)
Remove the following heating elements.
Start at the lowest heating element.
b) 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.
7. Clean the heating elements.
8. Replace the gasket.
9. Measure the resistance value between the two connections of each heating element.
The value needs to be approximately 19 +/- 4 Ohm for 3 kW elements and 10 +/-
2 Ohm for 6 kW elements.
10. Install all heating elements:
a) Place the element in the tank.
b) Tighten the heating element.
c) Attach the electrical wires earth (A) and live (L) on the element.
11. Install the isolating material.
12. Close the door.
13. Fill the water heater (see 8.6.1).
Fig. Remove a heating element
10.3 Performance check
Make sure that the resistance value of each element is correct:
1.
Open the door of the water heater.
Warning
Live cables inside! Switch off the power supply completely (on local isolator) before
opening the outer door to access the electrical components.
2. Remove the isolating material.
3. Measure the resistance value between the two connections of each heating element.
The value needs to be approximately 19 +/- 4 Ohm for 3 kW elements and 10 +/-
2 Ohm for 6 kW elements.
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0313853_DRE PLUS_ENNLFR_V3.0, 20-06-2023 65
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