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SHT Heiztechnik,
aus Salzburg
Operating instructions
M21/HB M27/GB
Page 56
SHT Heiztechnik aus Salzburg GmbH, A-5020 Salzburg-Bergheim, Rechtes Salzachufer 40 Tel. 0662-450444-0, Fax-DW 9
Our current general terms and conditions apply.Errors, printing faults and technical changes reserved
10.4
Reset STL and change fuse
If the boiler overheats the STL = Safety temperature limiter switches parts of the electronics off. If the
STL has triggered the boiler can no longer heat until the STL is reset by hand. This can only be carried
out for a cooled boiler (less than 85°C boiler temperature).
If the fuse is blown, the entire electrical system of the boiler closes down. No heating is possible until
the fuse has been renewed.
Switch of the current to the complete system before changing the fuse!
Unlock STL Step 1
Unlock STL Step 2
Unlock STL Step 3
1.
First unscrew the STL cover cap.
2.
Unlock the STL by pressing it with a ball-point pen, for example, until an audible click is heard The
STL engages (does not function until the temperature drops!)
3.
Re-fit cover cap.
Open circuit board cover
Position of fuse & fuse switch
r
Cut off all power of the
installation before changing
the
fuses.
(Unplug
the
insertion turbine too)!
1.
Open the revision lid at the
rear right of the side cover by
unscrewing 5 sheet metal
screws.
2.
The fuse is located at the rear
middle part of the main circuit
board and the fuse holder
(fuse F10 AT). Remove the
fuse holder and exchange the
fuse.
3.
Subsequently, re-insert the fuse holder with new fuse and close the fuse box with the circuit
board cover.