Titus FFDE/FFDER/FFDERA User Manual

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I N S T A L L A T I O N & O P E R A T I O N M A N U A L

FFDE, FFDER, FFDERA Models

Fan Filter Unit IOM

Installation & Operation

T E C H N I C A L N O T E S

FFDE, FFDER, and FFDERA units are not recommend for use with ducted systems, and
cannot operate with inlet static pressure exceeding 0.30 in wg.

For applications when you use a VAV box or Constant Airflow Terminal, Duct Collars or Fan
coils. The design engineer must advise the contractor or air balancer that the air supply
needs to be balanced. If you do not balance the air supply properly you have the potential
to starve or over feed the fan with air causing the motor to stall which can damage the fan
motor. This also can be minimized by notifying Titus beforehand for assistance. The
ECM motors used in the FFDE, FFDER, and FFDERA designs are a Microprocessor
controlled motor and are designed to maintain a constant air volume. When two
controllers are compensating the air volume at the same time, the motor microprocessor
is unable to stabilize the airflow and will shut itself down if it cannot find a stable operating
point.

In addition to properly balancing the airflow to the Fan: you should prepare a sequence of
operations turning on FFU’s prior to energizing the Air Handler to prevent potential backward
rotation of the blower wheel which can prevent motor rotating in the proper direction and will
reduce airflow and cause eventual shutdown. The drive components inside the ECM motors
are self-testing and sized for the motor being used inside the unit they can’t compete with the
airflows from a duct blower motor.

Caution

For applications requiring powered fan filter units and a ducted connection our recommendation
would be to use FFD, FFDR, or FFDRA units equipped with PSC motors.

Designs with Duct Collar, VAV or constant air box and fan coils