Bryant 581J-17-28, Инструкции по обслуживанию и техническому обслуживанию

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Before changing pulleys to increase fan wheel speed,
check the fan performance at the target speed and airflow
rate to determine new motor loading (bhp). Use the fan
performance tables or use the Packaged Rooftop Builder
software program. Confirm that the motor in this unit is
capable of operating at the new operating condition. Fan
shaft loading increases dramatically as wheel speed is
increased.
EQUIPMENT DAMAGE HAZARD
Failure to follow this CAUTION can result in equipment
damage.
Drive packages cannot be changed in the field. For
example: a standard drive cannot be changed to a high
static drive. This type of change will alter the unit’s
certification and could require heavier wiring to support
the higher amperage draw of the drive package.
CAUTION
!
NOTE
:
Drive packages cannot be changed in the field.
For example: a standard drive cannot be changed to a high
static drive. This type of change will alter the unit’s
certification and could require heavier wiring to support
the higher amperage draw of the drive package.
To reduce vibration, replace the motor’s adjustable pitch
pulley with a fixed pitch pulley (after the final airflow
balance adjustment). This will reduce the amount of
vibration generated by the motor/belt-drive system.
To determine variable pitch pulley diameter, perform the
following calculation:
1.
Determine full open and full closed pulley diameter.
2.
Subtract the full open diameter from the full closed
diameter.
3.
Divide that number by the number of pulley turns
open from full closed
This number is the change in pitch datum per turn
open.
EXAMPLE:
–
Pulley dimensions 2.9 to 3.9 (full close to full open)
–
3.9 - 2.9 = 1
–
1 divided by 5 (turns from full close to full open)
–
0.2 change in pulley diameter per turn open
–
2.9 + 0.2 = 3.1” pulley diameter when pulley closed
one turn from full open
CONDENSER COIL SERVICE
ROUND TUBE PLATE FIN (RTPF)
CONDENSER COIL
The condenser coil is fabricated with round tube copper
hairpins and plate fins of various materials and/or coatings
(see the Model Number Nomenclature in Appendix 1 to
identify the materials provided in this unit). The coil may
be one
− row or composite − type two − row. Composite
two − row coils are two single − row coils fabricated with a
single return bend end tubesheet.
Recommended Condenser Coil Maintenance
and Cleaning
Routine cleaning of coil surfaces is essential to maintain
proper operation of the unit. Elimination of contamination
and removal of harmful residues will greatly increase the
life of the coil and extend the life of the unit. The
following maintenance and cleaning procedures are
recommended as part of the routine maintenance activities
to extend the life of the coil.
Remove Surface Loaded Fibers
Surface loaded fibers or dirt should be removed with a
vacuum cleaner. If a vacuum cleaner is not available, a
soft non − metallic bristle brush may be used. In either
case, the tool should be applied in the direction of the fins.
Coil surfaces can be easily damaged (fin edges can be
easily bent over and damage to the coating of a protected
coil) if the tool is applied across the fins.
NOTE : Use of a water stream, such as a garden hose,
against a surface loaded coil will drive the fibers and dirt
into the coil. This will make cleaning efforts more
difficult. Surface loaded fibers must be completely
removed prior to using low
− velocity clean water rinse.
Periodic Clean Water Rinse
A periodic clean water rinse is very beneficial for coils
that are applied in coastal or industrial environments.
However, it is very important that the water rinse is made
with a very low − velocity water stream to avoid damaging
the fin edges. Monthly cleaning as described below is
recommended.
Routine Cleaning of Coil Surfaces
Periodic cleaning with Totaline environmentally sound
coil cleaner is essential to extend the life of coils. This
cleaner is available from Bryant Replacement
Components Division as
p/n: P902- 0301 for one-gallon
(3.8L) container, and P902- 0305 for a 5-gallon (18.9L)
container
. It is recommended that all coils, including
standard aluminum, pre − coated, copper/copper or
E − coated coils be cleaned with the Totaline
environmentally sound coil cleaner as described below.
Coil cleaning should be part of the unit’s regularly
scheduled maintenance procedures to ensure long life of
the coil. Failure to clean the coils may result in reduced
durability in the environment.
Avoid use of:
coil brighteners
acid cleaning prior to painting
high pressure washers
poor quality water for cleaning