Unitary Packaged Units:

The indoor and outdoor units are both contained in a self-contained ‘unitary’ housing, often installed as a ‘through the wall’ unit. The unit may be reversible allowing operation as a heat pump, or electric resistance heating may be included.
These types of systems are categorised as Level 3 and simple procedure generally considered suitable for these systems.
Such packaged units or systems usually include self-contained ‘on-board’ controls for temperature, and may include a timer control function.

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