The Upper Fan has a Louver and fan box in front of it that is normally attached.  This photograph is to show the fan module before the louver is added.  The DOAS (Dedicated Outdoor Air System ) is shipped with the fan modules removed and packed around the ERM (Energy Recovery Module) as shown:

Only the exhaust fan on the bottom needs to have power line reattached, with toggle type wire attachments.  After the fresh air intake fan module and exhaust fan module are installed to the transition ductwork to the ERM, the exhaust fan power line can be reattached.  The fan itself has capacitor and internal wiring already attached.  See as follows:

The ground wire (green) is inserted into the ground opening a instrument flathead screw driver is used to insert the ground as shown as follows:

After inserting the green wire into ground, make sure it is firmly attached.


Next move on to the white wire and notice this is a hand toggle type wire attachment.  Gently pull up on the N orange toggle (white wire or neutral) and insert fully and close toggle as follows:

Next, attach black wire and insert into L (load or black wire) as follows:

Main Power tie in is as follows:

The red control wire is control 24 VAC and is in place for unit start-up.  To be wired with duct smoke sensor after the ductwork and smoke sensor is in place.


The DOAS system has been assembled and tested as a working system to verify relay shuts off fans when control wire is opened or the smoke or RTU binary point is open.


The relay is a 30 amp contactor relay as used for most HVAC motors or compressors.


The transformer is a 120 VAC to 24 VAC control wiring transformer.


We have 120, 220, 250, 440 transformers as needed for different projects.


The relay and transformer module is shown below.

Please contact BPE at or call 201-722-1414 if there are any questions.

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