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SAFETY UNIT
Description
Safety units are components used in domestic hot water
installations for protecting hot water accumulators. The
models for solar heating installations are specifically designed
for use in thermo-syphon water heaters where the accumulator,
and therefore the safety unit, are installed outdoors.
Safety units are made up of different components, with the
following functions:
Safety: to prevent the water pressure in the accumulators from
reaching dangerous values.
Anti-pollution: to prevent the hot water returning to the cold
water supply network and contaminating the water in the water
heater with discharge water.
Isolation: to isolate the supply network and allow maintenance
and control of the accumulator and the installation.
Technical characteristics
· Special stamped brass body, Cu Zn 40 Pb2, EN 12165.
· EPDM safety valve closure gasket.
· PPS non-return valve.
· Safety valve shaft material: stainless steel.
· External elements resistant to UV radiation.
· Nominal pressure of safety valve regulation: 7 bar
· Safety valve closing pressure
· For cold water: > 6.3 bar.
· For steam: > 5.25 bar
· Non-return valve opening pressure: < 0.2 bar.
· Non-return valve seal pressure: > 0.03 bar
Safety units are certified in accordance with European Standard
EN 1487 by the CSTB and BELGAQUA Institutes.
SOLAR THERMAL CONTROLS
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