CDXQ SERIES
****** W ARNING ******
Unit must not be operated
during building construction
due to excessive airborne dust
and debris. The unit must not
be operated under any
circumstances without an air
filter in place.
****** W ARNING ******
Any devices such as fan
switches or thermostats that
have been furnished by the
factory for field installation
must be wired in strict accordance with the wiring diagram
that is supplied with the unit.
Failure to do so could result
in damage to components
and will void all warranties.
Fan Coil Units
INSTALLATION, OPERATION & MAINTENANCE INSTRUCTIONS
**WARNING TO INSTALLER, SERVICE PERSONNEL AND OWNER**
Altering the product or replacing parts with non authorized factory parts voids all warranty or implied warranty
and may result in adverse operational performance and/or a possible hazardous safety condition to service
personnel and occupants. Company employees and/or contractors are not authorized to waive this warning.
Current Maintenance Program is available at www.firstco.com under "Product Information".
GENERAL
The manufacturer assumes no responsibility for equipment installed in
violation of any code requirement.
These instructions give information
relative to the installation of these fan
coil units only. For other related
equipment refer to the proper instructions.
Material in this shipment has been
inspected at the factory and released
to the transportation agency in good
condition. When received, a visual
inspection of all cartons should be
made immediately. Any evidence of
rough handling or apparent damage
should be noted on the delivery receipt and the material inspected in
the presence of the carrier’s representative. If damage is found, a claim
should be filed against the carrier
immediately.
Note: State of MA.-248 CMR code of the
state of MA. requires a pump timer (60
seconds on every 6 hours). See diagram.
FAN COIL UNIT
The installer must adhere strictly
to all local and national code requirements pertaining to the installation of
this equipment.
These units are designed for installation in a horizontal position.
The CDXQ is designed for free return
installation (non-ducted return air),
therefore the furred down area must
be completely sealed (except return
air grille) to ensure that all return air is
pulled from the conditioned space
and not from other areas of the building structure.
Access must be provided for servicing the unit. If this access is provided
by a removable ceiling panel, ample
space must be allowed for removal of
the blower panel and to provide access to electrical and plumbing controls.
All CDXQ units are U.L. listed for
installation with zero inches clearance to combustible materials. This
includes the unit cabinet, discharge
plenum and connecting ducts.
AIR DISTRIBUTION
DUCTS
All duct work must be installed in
accordance with National Fire Protection Association Codes 90A and
90B. Ducts should be adequately
insulated to prevent condensation
during the cooling cycle and to minimize heat loss during the heating
cycle. All return air must be filtered to
prevent dirt buildup on the coil surface. If there is no ducted return,
applicable installation codes may
limit the unit to installation only in a
single story residence. In many
cases it is acceptable to use ducting
of the same size as the fan coil
connections. However, unique ar-
rangements or long duct runs must be
confirmed by a local professional.
The manufacturer will not be responsible for misapplied equipment.
ELECTRICAL
All wiring must comply with local
and national code requirements.
Units are provided with wiring diagrams and nameplate data to provide
information required for necessary
field wiring.
These units are provided with a
Class 2 transformer for 24-volt control
circuits. Should any add-on equip-
ment also have a Class 2 transformer
furnished, care must be taken to prevent interconnecting outputs of the
two transformers by using a thermostat with isolating contacts.
INSTALLATION
PRECAUTIONS
Installation of this fan coil should
only be performed by properly trained
personnel to ensure proper installation and the safety of the installer.
L250 2/09
The following are some precautions to
****** WARNING ******
Do not touch any rotating
component with any object.
Damage to the equipment and
personal injury can occur.
****** WARNING ******
When connecting piping to
fan coil units, do not bend or
reposition the coil header tubing for alignment purposes.
This could cause a tubing fracture resulting in a water leak
when water pressure is applied to the system.
be followed for typical installations.
• Always use proper tools and equip-
ment.
• No wiring or other work should be
attempted without first ensuring that
the fan coil is completely disconnected from the power source and
locked out. Always verify that a good
ground connection exists prior to energizing any power sources.
• Always review the nameplate on
each unit for proper voltage and control configurations. This information
is determined from the components
and wiring of the unit and may vary
from unit to unit.
• When soldering or brazing to the
unit, it is recommended to have a fire
extinguisher readily available. When
soldering close to valve packages or
other components, heat shields or
wet rags are required to prevent damage.
• When the fan coil unit is in opera-
tion components are rotating at high
speeds.
• Units must be installed level to
ensure proper drainage and operation. These fan coils have a pitched
drain pan for improved condensate
drainage.
• Check unit prior to operation to
ensure that the condensate water will
drain toward the drain connection.
An overflow drain or an auxiliary drain
pan under the fan coil may be required as a back up to a clogged
primary drain.
• Be sure that the drain pan is free
from foreign material prior to start up.
• Check filter media installation to
ensure that it is installed correctly.
Use the directional arrows or other
information on the filter to determine
the proper flow direction.
• Ensure that the air distribution sys-
tem does not exceed the external
static rating of the unit.
COOLING COIL PIPING
The CDXQ fan coil units are supplied with a direct expansion refrigerant coil. The refrigerant metering
device is a fixed orifice piston and is
installed at the factory. This permits
the unit to be matched with either a
standard condensing unit or heat
pump. The suction and liquid refrigerant lines must be sized in accordance
with the outdoor unit manufacturer’s
recommendations.
Condensate drain lines must be
installed with adequate slope away
from the unit to assure positive drainage. Since the drain pan is located on
the suction side of the blower, a
negative pressure exists at the drain
pan and a minimum trap of 1-1/2
inches should be provided in the drain
line to assure proper drainage. The
fan coil unit may be located where the
return air space is large enough that a
negative pressure is not present,
however, a trapped condensate line is
recommended in case a negative
condition should occur, the unit would
drain properly.
NOTE: If a Condensate Overflow
Shut-off Switch, that is designed to
be installed in the drain line, is used
in place of a secondary drain line, then
the cut-off switch should be located
in the primary drain line between the
fan coil unit and the P-trap.
HOT WATER COIL
PIPING PRECAUTIONS
• Flush all field piping prior to connec-
tion to remove all debris.
• Use wet cotton rags to cool valve
bodies when soldering.
• Open all hand valves midway prior to
soldering.
• When soldering to bronze or brass,
heat the piping while in the socket/
cup and begin introducing the solder
when the flux boils rapidly.
Avoid direct flame into the solder joint.
• Heat can only be applied to the cup
of the valve body for a minimal time
before damage occurs (even with the
use of wet rags.
• Avoid rapid quenching of solder
joints as this will produce joints of
inferior quality.
• Connect all piping per accepted
industry standards and observe all
regulations governing installation of
piping systems. When all connections are complete the system must
be pressure tested. Repair any solder joint leaks and gently tighten any
leaking valve packing nuts and piping
accessories as required. Water systems are not designed to hold pressurized air and should only be tested
with water.
NOTE: A water heater is designed to
produce hot water. Hot water represents a serious safety hazard due to
potential scalding. The temperature
of water normally required to provide
space heating (135 to 140 degrees)
may be hotter than certain codes
allow for domestic hot water. An “antiscald valve” can be installed in the hot
water piping that would allow the domestic water to be supplied at a lower
temperature than the space heating
water. These can be obtained locally
and should be installed according to
the manufacturer’s installation in-
structions.
HOT WATER COIL PIPING
The hot water coil connections are
1/2” inch nominal (5/8” OD) copper.
All piping between the water heater
and fan coil unit should be 3/4” nominal (7/8” OD) to prevent excessive
head pressure losses and should not
exceed 200 feet of total piping. (Consult the factory for other piping applications.)
It is also recommended that all
piping be adequately insulated to pre-
****** WARNING ******
An expansion tank may be
required if a back-flow
preventer is installed in the
system.