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Issue 1 06/02/20
7
Commissioning
7.3.2 Flow performance
When initially opening hot outlets a small surge in flow may be
noticed as pressures stabilise. This is quite normal with
unvented systems. In some areas cloudiness may be noticed in
the hot water. This is due to aeration of the water, is quite
normal and will quickly clear.
7.3.3 Temperature controls
The cylinder units are fitted with a thermostat and thermal cut-
out. These controls must be wired in series with the 2 port
motorised zone valve supplied to interrupt the flow of primary
water around the heat exchanger coil when the control
temperature has been reached.
Do Not bypass the thermal cut-out(s) in any circumstances.
7.3.4 Operational faults
Operational faults and their possible causes are detailed in the
Fault Finding section of this book. It is recommended that faults
should be checked by a competent installer.
The air volume within the expansion vessel supplied in the
unvented system kit will periodically require recharging to
ensure expanded water is accommodated within the system. A
discharge of water INTERMITTENTLY from the expansion
valve will indicate the air volume has reduced to a point where
it can no longer accommodate the expansion.
See
See Section 10 Page 32 for fault finding
