Hitachi ZA3000 Series Instruction Manual page 489

(2) Turn the magnet for flame clockwise at 90°. Disconnect the
cooling water tubes after confirming that the water is not flowing.
Then, pull out the burner head.
Fig. 1-13 Removal of Burner Head
(3) Remove two shield-fixing screws in the front side of the magnet.
(4) Turn the magnet counterclockwise at 180°. Then, remove
another two shield-fixing screws.
(5) Attach the heat shield plates inside of the magnet and fix loosely
with the fixing screws.
Fig. 1-14 Installation of Heat Shield Plates
(6) Turn the magnet to the opposite direction at 180°, and fix the
shield plates with the fixing screws in the opposite side a little
tightly.
1 - 13
Shield-fixing screws
Heat shield plates