48
If not included on the unit or furnished from the factory,
supply and return grilles should be provided as recommended
in the product catalog.
Step 7 — Make Final Preparations
1. Turn off power to the unit (open unit electrical disconnect).
2. Install thermostats and perform any other final wiring as
applicable. Check the unit for any loose wires.
3. Perform a final visual inspection. All equipment, ple-
nums, ductwork, and piping should be inspected to verify
that all systems are complete and properly installed and
mounted, and that no debris or foreign articles such as pa-
per or drink cans are left in the units or other areas. Clean
dirt, dust, and other construction debris from unit interior.
Be sure to check fan wheel and housing.
4. Rotate fan wheel by hand to be sure it is free and does not
rub housing. Check that wing nuts securing fan assembly
to fan deck are tight.
5. Ensure all panels and filters are installed before checking
fan operation. Turn on power to the unit.
6. Install filter in frame at front of coil. If field-supplied
filters are used, be sure size is as specified in Tables 1-3.
7. ECM (Electronically Commutated) Blower:
If the unit is equipped with an ECM blower, additional
steps may be required during the air balancing process.
The ECM blower is controlled by one of three control
boards, depending on the options ordered with the unit.
Review project submittals or order acknowledgment to
determine which ECM control scheme the unit has. Alter-
natively, match the control board to the illustrations iden-
tified in the Control Board Type section.
8. Check the fan and motor operation.
9. Be sure drain line is properly and securely positioned and
that the line is clear. Pour water into drain to check
operation.
10. Prior to the water system start-up and balancing, the
chilled/hot water systems should be flushed to clean out
dirt and debris which may have collected in the piping
during construction. During this procedure, the system
should be flushed from the supply riser to the return riser
through a cross-over loop at the end of the riser column,
and all unit service valves must be in the closed position.
This prevents foreign matter from entering the unit and
clogging the valves and metering devices. Strainers
should be installed in the piping mains to prevent this ma-
terial from entering the units during normal operation.
Vent all air from unit coil and related piping. Air venting
from the unit is accomplished by the use of the standard
manual air vent fitting, or the optional automatic air vent
fitting installed on the coil. Venting can be accomplished
by depressing the needle valve core. Automatic air vents
may be unscrewed one turn counterclockwise to speed
initial venting, but should be screwed in for automatic
venting after start-up operations. When steady stream of
water begins to escape, close valve. Vent release air slow-
ly, usually dripping water into drain pan in the process.
Make sure all service valves are open and that the motor-
ized control valves, if supplied, are set for automatic
operation.
11. Check all control valves in the system for proper opera-
tion in accordance with valve manufacturer's instructions.
12. For units with factory-installed ball valves with lever han-
dles — When handle is perpendicular to valve body, there
is no flow through valve. Ball valves may be used as
shutoff valves.
ECM CONTROL OPTION.
3-Discrete Speed Potentiometer Field Adjustment (See
Fig. 41) — The unit has been factory configured to produce
PSC equivalent airflow on high speed, with medium and low
speed set at 80% and 60% of high, respectively. If these set-
tings are acceptable, then no further configuring is required.
If alternative airflows are desired, use board mounted pots
to adjust the airflow associated with each input. Each output
can be adjusted from 0 to 100% of the motor’s factory pro-
grammed operating range. Use voltmeter and airflow chart (on
control box cover) to set values. Refer to Appendix A for ad-
justment procedure.
4-Discrete Speed Potentiometer Field Adjustment, Solid
State — The unit has been factory configured to produce PSC
equivalent airflow on high speed, with medium and low speed
set at 80% and 60% of high, respectively. If these settings are
acceptable, then no further configuring is required.
Board mounted pots are provided to adjust the airflow per-
taining to each output. Each output can be adjusted from 0 to
100% of the motor’s factory programmed operating range. Use
voltmeter and airflow chart (on the control box cover) to set
values. Refer to Appendix B for adjustment procedure.
Variable Airflow for 0-10 Vdc Input
— No control board is
required and no field adjustments are possible. Motor uses 0-10
CAUTION
Do not start up or operate unit without filter. Be sure filter
and unit interior are clean. Failure to do so could result in
damage to the equipment or building and furnishings and/
or void all manufacturer's warranties.
CAUTION
The air vent provided on the unit is not intended to replace
the main system air vents and may not release air trapped
in other parts of the system. Inspect the entire system for
potential air traps and vent those areas as required, inde-
pendently. In addition, some systems may require repeated
venting over a period of time to properly eliminate air from
the system. Failure to properly vent system may negatively
affect operation.
CAUTION
Both of the procedures described below require the control
box to be powered while adjustments are made. Line volt-
age components are concealed behind a secondary cover.
However, installer should still take all reasonable precau-
tions to prevent electrical shock.
L2
LOW
MED
HIGH
VR1
VR2
VR3
K1
K2
K3
LOW
MED
HIGH
COM
C1
C2
C3
CR1
L1
POTS
Fig. 41 — 3-Speed Potentiometer Adjustment
To Next Page
Loading...
