FLOWMAX 170 - Draining the Central Heating and Domestic Hot Water System

MAINTENANCE INSTRUCTIONS
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6.6 Draining the central heating system
If the need arises to drain the system, this can be
done as follows:
• Switch the system to “WINTER” mode and ignite
the water heater.
• Switch off the power supply to the water heater.
• Wait for the water heater to cool down.
• Connect a hosepipe to the system drain point R
and locate the other end of the hose in a suitable
drainage system.
• Open the system drain valve (fig. 1).
• Open the air vents on the radiators, starting with
the highest and moving down the system to the
lowest.
• When the system has been drained, close the
radiator breather valves and the drain valve.
• If only the water heater needs to be drained,
close the flow/return isolating valves on the heating circuit and open the drain valve R located at the
bottom of the water heater on the pump manifold (see fig. 1 );
Draining the domestic hot water system
If there is a danger of freezing, the domestic hot water system should be drained. This can be done as follows:
• Close the mains water supply valve.
• Open all the hot and cold water taps.
• On completion, close all the previously opened taps.
R
Fig. 1