The changeover (aquastat) switch is factory wired to the DDC controller as shown on the unit wiring diagram. During installation in the field, this switch must be clamped onto the pipe supplying water to the unit upstream of the valve. See the unit ventilator IOM for more details.
My Magic Aire Unit Ventilator has factory installed DDC Controls, but I can not bring on the condensing units. Is there something wrong with my Controller?
For units with DX coils and Magic Aire DDC Controls, Magic Aire provides a relay that is to be field connected to the remote field supplied and installed compressor/condenser. Magic Aire’s control transformer is only to be used for factory supplied equipment. A separate transformer must be field supplied for field supplied equipment such as compressors. See unit wiring diagram for wiring details.
The drain pan is sloped toward side with largest coil’s connections or the DX coil connections. For example, a unit with a 2-row right hand water coil and a 4-row left hand water coil will have the drain pan sloped down to the left hand side. The uphill connection is sealed with a plug and the downhill field connection is covered with a plastic cap except when the drain pan is stainless steel, then both connections are sealed with a plug. The slope may be reversed in field. See Installation Manual for details.