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22
AST 14 C 257/00
DHW FLOW METER/SWITCH
(Version KC only)
The DHW flow meter contains a magnet switch, the position of which determines the
minimum amount of domestic water needed to start up the boiler
(3 l/min ON and 1 l/min
OFF)
. If the request for DHW does not exceed this value, the microswitch does not close
the contact, which prevents the boiler from switching on and avoids the risk of boiling at
very low flow rates. Based on different outputs, the main difference between the flow
meters is the flow-limiting device (or flow regulator), which determines the litres/minute that
can be drawn at ût 30K:
PROTECTION FILTERS
To prevent dirt from building up in the primary exchanger and damaging it, it is advisable
to clean the system thoroughly before initial start-up.
Safeguarding the primary exchanger body is fundamental to ensure efficient boiler
operation.
Excessive build-up of dirt leads to load losses in the heating circuit and consequently a
drop in flow rate. If the flow rate is below the value requested by the heating flow meter,
there is a boiler shutdown due to heating water circulation malfunction.
For this reason, it is mandatory to mount an accessible Y-type filter with
Ø 0.4mm mesh on the return line before the boiler inlet.
Regulator flow rate
- 24 kW, 13 l/min regulator
- 28 kW, 14 l/min regulator
- 32 kW, 16 l/min regulator
RETURN
LINE
BOILER
INLET
DIRT
BUILD-UP