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6. CONNECTIONS
6.1. DUCT CONNECTIONS
Return air, fresh air, exhaust air and supply air ducts should be fixed (connected) to the unit with flexible
connection. Required leak-proofing should be obtained in order to ensure desirable air flow. Having improper
(bad) unit
– duct connections and wrong dimension, shape and duct fragments inside of the connection may
cause a turbinated air flow.
When air flow direction is changed at fan blowing outlet, excessive losses may occur. If this is compulsory,
connections should be done as Figure 6.1.1. The length of duct, before the elbow or electrical heater, should
be double of the outlet-diameter.
Figure 6.1.1. Duct Connections Schema (Changing the direction of air flow)
6.2. DRAIN CONNECTIONS
The diameter of drain pipe should be equal the diameter of drain pipe on the unit. Drainage pipe and drain pan
connections should be made by ripple and flange to be able to dismantle pipe connections easily in order to
clean up the residue occurred on drain pan and pipes.
The pipe coming out of the drain pan should be connected to a U or P shaped flusher pipe and should be filled
with water in order to not to cause air suction as described below.(Figure 6.2.2.)
Figure 6.2.2. P-Shaped Flusher Application
6.3. ELECTRICAL CONNECTIONS
ALL ELECTRICAL CONNECTIONS SHALL BE DONE ACCORDING TO EN 60204-1
BY TRAINNED AND AUTHORIZED PERSONEL
