Daikin Myzone 3 - System Design Considerations; Designing the Correct Constant Zone

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System Design Considerations
Designing the Correct Constant Zone
All ducted air conditioning systems should have a percentage of air passing over the indoor coil at all times. This is a safety mechanism to protect the
ductwork and the A/C unit.
There are several ways of achieving this when designing a ducted air conditioning system.
i. Fixed Ducted Constant Zone
A fixed duct constant zone requires the system to be designed with one zone that has no zone damper fitted to it. This is normally a large common area (e.g. main living area).
The downside with this configuration is that air will always be delivered to this area regardless of whether it is occupied or not. This reduces the eciency of the system and
does not allow for modulating temperature control in the zone.
ii. Electronic Constant Zone
This option requires the system to be designed with one zone that has a zone motor fitted to it, which will automatically open if all other zones are closed. With electronic
constants there are three options available as follows:
a. Standard electronic constant zone
Typically a zone damper would be fitted to the main living area in the home or a common area in an oce building. This zone can be used like any other zone but will be
automatically overridden open if required by the system to maintain the minimum airflow over the indoor coil. With a Myzone system you can select as many zones as
you need to be electronic constants and they will activate and deactivate progressively as required. Standard electronic constant zone is only Open/Closed.
b. Dedicated electronic constant zone
In this option an additional zone is installed into the system serving an unoccupied area such as a stairwell or hallway. This zone is let in the closed position and will
only open if required by the system. With a Myzone system you can select as many dedicated zones as you need. The benefit of the dedicated electronic constant zone is
that all occupied areas can have individual temperature control and if the electronic constant is required to operate it will not aect the comfort of the occupants.