Investigating Noise Complaints; Controls; Electric Duct Heater - Daikin MQFVI5 Installation And Maintenance Manual

Investigating Noise Complaints

Noise from a terminal can be due to a variety of conditions,
and can be difficult to eliminate. The first step is to isolate the
type, source and direction. Generally, noise heard at the air
outlet is considered a discharge type. Noise heard through the
ceiling is considered a radiated noise. For detailed information
concerning noise transmission in buildings see ARI Standard
885-98, Procedure for Estimating Occupied Space Sound
Levels in the Application of Air Terminals and Air Outlets.
Discharge Noise
Discharge noise is usually caused by high static or little
to no internal duct lining downstream of the terminal, or it
can sometimes be caused by the air outlet itself. Air outlet
generated sounds can be reduced by reducing flow or
increasing air outlet size. Reducing static pressure, or flow, or
adding additional attenuation materials will reduce discharge
sounds from the terminal unit. Sometimes, moving the flex duct
between the terminal and air outlet so the air must make an
additional turn will help with the discharge sound.
Radiated Noise
Radiated noise is most commonly associated with fan powered
terminal units. Proper suspension, isolation and ducting of
these terminals are critical to minimize any vibrations from
being transmitted through the suspension or ductwork. Severe
vibrations, or any sounds of knocking or rubbing should be
immediately investigated and the terminal shut off. Occasionally,
shipping/handling/installing can unbalance a blower.
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Controls

Contact your Daikin representative for information concerning
controls provided by Daikin. For controls provided by others,
contact the local control representative for assistance.

Electric Duct Heater

Electric shock hazard . Can cause personal injury or
equipment damage .
This equipment must be properly grounded. Connections and
service to the MicroTech III Chiller Unit Controller must be
performed only by personnel knowledgeable in the operation
of the equipment being controlled.
Static sensitive components . Can cause equipment
damage .
Discharge any static electrical charge by touching the bare
metal inside the control panel before performing any service
work. Never unplug cables, circuit board terminal blocks, or
power plugs while power is applied to the panel.
If the heater does not operate:
• Check electric power into the unit, and verify that the
wiring agrees with the label diagram located on the
terminal unit casing.
• Verify that the unit is installed properly (i.e., according
to the air flow orientation label). Review the wiring
diagram supplied with the heater to verify the field wiring
is correct and of the proper gauge and that the heater is
properly grounded.
If the heater cycles ON and OFF:
• Verify that the airflow is uniformly distributed across the
face of the heater. Check for obstructions in the duct, or
insufficient air flow (CFM) (see label for minimum CFM).
If conditioned space fails to warm-up:
• Make certain that the heater controls and the thermostat
are compatible and wired properly. Relocate the
thermostat if it is located in a position that is too warm.
If conditioned space overheats:
• Make certain that the heater controls and the thermostat
are compatible and wired properly. Relocate the
thermostat if it is located in a position that is too cool.
Verify that the air distribution to the space is appropriate
for the required thermal load.
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WARNING
CAUTION
IM 1102 • PARALLEL TERMINAL BOX