6
Installation
The system consists of
•
Air Handling Unit (AHU) unit usually located in the attic
•
Intake and exhaust vents leading to outside
•
Ducting to facilitate the transport of air to and from this unit to the various rooms
•
Ceiling terminals for the delivery and extraction of air in rooms
•
Control switches
The Air Handling Unit (AHU) is located in either the attic or a utility area. It contains
a high efficiency counter-flow heat exchanger, fans to drive air in and out and filters to
clean the air. It is mains powered (220V) from a standard 13Amp socket. It is
suspended by light chain from the rafters and supported slightly proud of the ceiling
joists. This is for two reasons, (a) to prevent any vibration and (b) to allow house
insulation under the unit.
The outer casing is made of polypropylene and is insulated on the inside where
possible to minimise noise levels and heat loss. It is just off level. This helps the egress
of water through the condensate drain. This is a 15mm plastic hose from the unit to the
outside. It has been provided to assist in the disposal of any water that may result from
condensation.
One end of the unit is connected to outside in order to take in fresh air and exhaust
stale air. There are a few options for this:
1.
Duct connections to slate vents.
2.
Duct connections to soffits
3.
Duct connections to gables
4.
A combination of any of above
The outdoor and intake vents have been reasonably separated to ensure that the
exhaust air is not collected as fresh air.
