78
Step 6 — Frame and Finish Unit
EXPOSED UNIT FINISH, TOUCH-UP AND REPAINT
Return access and exposed cabinet units may be furnished with a
baked enamel finish. Small scratches in this finish may be repaired
with touch-up paint available from the factory. Some colors of
touch-up paint are available in aerosol containers and all touch-up
paint is available in pint, quart, and gallon cans.
To repaint the factory-baked enamel, the finish should be prepared
by light sanding with no. 280 grit sand paper or no. 000 or
no.
0000 fine steel wool. The surface may also be wiped with a
liquid surface etch cleaning product such as “No Sand” or
“Pasceo.” These items should be available at most paint product
stores. It should be noted that the more conscientiously this prepa
-
ration is done, the more effective it will be.
After this preparation is accomplished, the factory finish should
provide excellent adhesion for a variety of air-dried top coats.
Enamel will give a more durable, higher gloss finish, while latex
will not adhere as well and will give a dull, softer finish. Top coats
involving an exothermic chemical process between two compo
-
nents, such as epoxies and urethanes, should be avoided.
Factory aerosol touch-up paint may require a number of light
“dust coats” to isolate the factory-baked enamel finish from the
quick drying touch-up paint.
Step 7 — Cut Out Openings for Grilles and
Thermostats
On all units with optional supply-air or return-air grilles, dampers,
thermostats, and switch plates, cut out openings where specified
on the job plans. Be careful not to cut wires, piping or structural
supports.
For remote-mounted thermostats, use a steel thermostat shield ring
to protect drywall from thermostat wiring where applicable.
If not included on the unit or furnished from the factory, supply
and return grilles should be provided as recommended in the prod
-
uct catalog.
Step 8 — Make Final Preparations
1. Turn off power to the unit (open unit electrical disconnect)
and install lockout tags on all power supplies to unit.
2. Install thermostats and perform any other final wiring as
applicable. Ensure all electrical connections are tight.
3. Perform a final visual inspection. All equipment, plenums,
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 paper 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 and clean, if necessary.
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. Adjust if necessary.
5. Install filter in frame at front of coil. If field-supplied filters
are used, be sure size is as specified in Table 4.
6. Ensure all panels and filters are installed before checking fan
operation. Turn on power to the unit.
7. Check the fan and motor operation.
8. Verify drain line is properly and securely positioned and that
the line is clear. Pour water into drain to check operation.
START-UP
General
Before beginning any start-up operation, the start-up personnel
should familiarize themselves with the unit, options and accesso
-
ries, and control sequence to understand the proper system opera-
tion. All personnel should have a good working knowledge of
general start-up procedures and have the appropriate start-up and
balancing guides available for consultation.
The building must be completely finished including doors, win-
dows, and insulation. All internal walls and doors should be in
place and in the normal position. In some cases the interior deco
-
rations and furniture may influence overall system performance.
The entire building should be as complete as possible before
beginning any system balancing.
The building breaker will be used as the disconnect switch. An ad-
ditional service switch may be installed on the unit.
The initial step in any start-up operation should be a final visual
inspection. All equipment, plenums, duct-work, 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 paper or drink cans are left in the units or other areas.
Each unit should be checked for:
• Free blower wheel operation
• Loose wires
• Loose or missing access panels or doors
• Clean filter of the proper size and type
Except as required during start-up and balancing operations, no
fan coil units should be operated without all the proper ductwork
attached, supply and return grilles in place, and all access doors
and panels in place and secure. Failure to do so could result in
damage to the equipment or building and furnishings, and/or void
all manufacturer's warranties.
Maximum operating altitude for units is 13,400 ft (4 km). All units
are IPXO rated.
Cooling/Heating System
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, 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 material from entering the units
during normal operation.
During system filling, air venting from the unit is accomplished by
the use of the standard, manual air vent fitting, or the optional, au-
tomatic air vent fitting installed on the coil. Manual air vents are
basically Schrader valves. To vent the air from the coil, depress the
valve until the air has vented the coil. When water begins to es
-
cape through the valve, release the valve. Automatic air vents may
be unscrewed one turn counterclockwise to speed initial venting,
but should be screwed in for automatic venting after start-up oper
-
ations. Refer to Fig. 86-87.
CAUTION
Proper safety procedures should be followed regarding venti-
lation and safety equipment during touch-up and repainting
since materials may pose a health hazard. The manufacturer's
directions should be followed for the products being used.
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, independently. In addi-
tion, some systems may require repeated venting over a period
of time to properly eliminate air from the system.
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