AirTouch 2 - 5.4 Spill or Bypass

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5.4 Spill or Bypass
Spill or bypass mode is a safety feature of the AirTouch 2+ system to prevent
pressure from building up and causing duct damage. This usually occurs if someone
has turned o all groups while the A/C unit is pumping air into the system leading
to a pressure build-up (and potential of duct puncture, blow-os or joints splitting).
It is designed to automatically open dampers if someone attempts to shut down all
dampers thus preventing pressure build up. Spill function opens the groups chosen
as spill groups in the system when all groups are being closed. Bypass function
opens the bypass damper which connects the supply duct to the return duct
directly when all groups being closed. When choosing groups for spill, it is strongly
recommended NOT to use bedrooms as spill groups. During sleep time if the air
conditioner is on and spill groups are forced to open, the spill groups will be very
cold or hot.
There is no dedicated bypass port. Any unused zone ports can be assigned as
bypass ports.
The system will maintain the number of groups chosen as spill groups or bypass
zones open at any time when AC is running. For instance, there will be at least two
groups open if two groups are chosen for spill. The rst group in the chosen spill
group list will open rst to spill. The opening percentage of the spill group or bypass
zone will march the required percentage to maintain the 100 (one spill group or
bypass zone), 200 (two spill groups or bypass zones) or 300 (three spill groups or
bypass zones) total opening of all dampers in the system.
Spill or Bypass
IMPORTANT: Choose at least one group as spill group unless there is a permanent
open zone used as spill zone. Otherwise, there will be no spill group when all zones
are closed and damage may be caused by high pressure building up inside ducts
if air conditioner is running. The Bypass and Spill cannot be set at the same time.