Stropuva DOMESTIC SOLID FUEL BOILER Operating Manual page 19

Fig. 5.5. Bi-thermal draugth regulator.
When metal and water becomes warmer, the boiler cylinder gets longer and lowers down the valve. When
temperature indications show not less than 80º C, open the valve with a temperature regulation screw (2);
and for higher indications – slightly close until temperature reaches 80° C. Later seeking to set a lower
temperature, turn a ring towards smaller figure. A ring cannot be turned behind the biggest figure (if
turned more, overheating and water boiling are possible).
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