Security Temperature Control (Stb ) Release - SUEVIA 303 Bedienungsanleitung

Security Temperature Control (STB ) Release

STB = Security Temperature Control
Its job ist to protect the heating element from an overheating!
The temperature control limiter (STB) is released when the maximum temperature is exceeded.
This only happens, when the air is in the heating unit (air bubbles -> no heat transmission!)
or if the water circulation is not functioning correctly. Possible reasons for this may be: e.g.
blockage or contamination (minerals/rust/lime/incrustation deposits) due to a damaged
non-return flap \ shut-off valve, or interrupted water flow, or opened by-pass line,
or heating element is fossil.
In case of air bubbles in the water circuit:
1. Bleed the pump, pos. (2)
2. Bleed the heating unit, pos. (5)
3. Bleed the water circuit, pos. (12)
4. Check, whether the automatic vent valve has been correctly installed.
(dry frost- and draught-protected room, highest point in the circuit)
Re-activation of the security temperature control limiter (STB) switch
- Put main switch on 0 = OFF
- Unplug heating element from the main current.
- Take away the slotted screw at the frontal side of heating element cage
- Heating element and STB have to be cooled down (otherwise STB does not snap in)
- Press in STB pushbutton with an insulated screw driver
--> click sound can be heard
- Screw in again the slotted screw
- Plug in the heating element
- Proceed to assembly and first startup again.
1) Slit-screw removes
2) Snap down presses until STB locks, clicks audibly.
Heating element:
Water temperature has to be adjusted at min. 20° C.
Attention -> the higher the temperature is adjusted, the more lime deposits!
Screw the heating element out or in only only at the hexagon steel plate.
24
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as in the case of first startup
STB
1
2
Switch off from
the main current
before opening.