English (GB)
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5. Product introduction
5.1 Product description
ALPHA1 L can be used as stand-alone or integrated circulator
pump in existing systems as replacement or in new systems with
either variable or constant flow rate.
5.1.1 Model type
These installation and operating instructions cover ALPHA1 L.
The model type is stated on the packaging and nameplate.
5.2 Applications
The pump is designed for circulating liquids in all kinds of heating
applications. The pumps are suitable for the following systems:
• Systems with constant or variable flows where it is desirable to
optimise the pump duty point.
• Installation in existing systems where the differential pressure
of the pump is too high during periods of reduced flow
demand.
• Installation in new systems for automatic adjustment of the
performance to flow demands without the use of bypass
valves or similar expensive components.
The speed can be controlled by a low-voltage PWM (Pulse Width
Modulation) signal.
High-efficiency ECM (Electronically Commutated Motor) pumps,
such as ALPHA1 L, must not be speed-controlled by an external
speed controller varying or pulsing the supply voltage.
5.3 Pumped liquids
In heating systems, the water must meet the requirements of
accepted standards on water quality in heating systems, for
example the German guideline VDI 2035.
The pump is suitable for clean, thin, non-aggressive and
non-explosive liquids, not containing solid particles, fibres or
mineral oil.
• Maximum water/propylene glycol mixture is 50 %
• Maximum 10 mm
2
/s viscosity
Note: The water/propylene glycol mixture reduces the
performance due to higher viscosity.
See section
for further information.
In domestic hot-water systems, we recommend that
you keep the liquid temperature below 65 °C to
eliminate the risk of lime precipitation.
CAUTION
Flammable material
Minor or moderate personal injury
- Do not use the pump for flammable liquids, such
as diesel oil and petrol.
CAUTION
Corrosive substance
Minor or moderate personal injury
- Do not use the pump for aggressive liquids, such
as acids and seawater.
