AO Smith ITS Serie Manuel D'installation, D'utilisation Et D'entretien page 31

3.2 Draining
0312734_ITS_400-1000_NLENFR_V4.1, 2024-01-22
1. Close the stop valve (4) between the cold water head tank and the cold water
inlet (A).
2. Open the drain valve (9).
3. Bleed the water heater (or installation) so that it drains completely.
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