FIELD: nonferrous metallurgy, specifically, electrolytic production of aluminum. SUBSTANCE: before start of repair electrolyzer is brought out of electrolysis without disconnection from electric network, electrolyte is removed with preservation of shorted circuit " anode-metal ", broken side blocks are taken out, new blocks are installed instead of removed ones, fettling is conducted with use of hearth mass in lower part of side blocks and is space " side block-hearth block ", voltage is raised to 4.0-6.0 V and electrolyzer is held under this voltage till liquid electrolyte is built up. Fettling from hearth mass is conducted in addition on both longitudinal sides of side block over its entire height. Time of electrolyzer being under state of shorted circuit " anode-metal "amounts to not more than 48 h. After built-up of liquid electrolyte under voltage 5.0-6.0 V additional pouring of liquid electrolyte may be performed. After fettling of hearth mass horizontal side sheet may be reclaimed. Burden containing hearth mass and alumina in proportion 1: (0.05-0.3) per cent by mass may be used for fettling. EFFECT: prolonged service life and increased productivity of electrolyzer, improved grading of produced aluminum, decreased labor input. 5 cl, 1 dwg, 2 tbl
