5
BEARINGS
This fan system uses bearings featuring concentric split lock-
ing collars. The collars are tightened through a cap screw
bridging the split portion of the collar. The cap screw has a
Torx T25 socket head. To tighten the locking collar: Hold the
locking collar tightly against the inner race of the bearing and
torque the cap screw to 65 to 70 in.-lb (7.4-7.9 Nm). See Fig. 7.
Fig. 7 — Tightening Locking Collar
MOTOR
When replacing the motor, also replace the external-tooth lock
washer (star washer) under the motor mounting base; this is
part of the motor grounding system. Ensure the teeth on the
lock washer are in contact with the motor’s painted base.
Tighten motor mounting bolts to 120 ± 12 in.-lb.
Changing fan wheel speed by changing pulleys:
The horsepower rating of the belt is primarily dictated by the
pitch diameter of the smaller pulley in the drive system (typi-
cally the motor pulley in these units). Do not install a replace-
ment motor pulley with a smaller pitch diameter than provided
on the original factory pulley. Change fan wheel speed by
changing the fan pulley (larger pitch diameter to reduce wheel
speed, smaller pitch diameter to increase wheel speed) or select
a new system (both pulleys and matching belt(s)).
Before changing pulleys to increase fan wheel speed, check the
fan performance at the target speed and airflow rate to deter-
mine new motor loading (bhp). Use the fan performance tables
or use the Packaged Rooftop Builder software program. Con-
firm that the motor in this unit is capable of operating at the
new operating condition. Fan shaft loading increases dramati-
cally as wheel speed is increased.
To reduce vibration, replace the motor’s adjustable pitch pulley
with a fixed pitch pulley (after the final airflow balance adjust-
ment). This will reduce the amount of vibration generated by
the motor/belt-drive system.
COOLING
Condenser Coil
The condenser coil is fabricated with round tube copper hairpins
and plate fins of various materials and/or coatings (see Model
Number Format in Appendix A to identify the materials provid-
ed in this unit). The coil may be one-row or composite-type two-
row. Composite two-row coils are two single-row coils fabricat-
ed with a single return bend end tubesheet.
Condenser Coil Maintenance and Cleaning Rec-
ommendation
Routine cleaning of coil surfaces is essential to maintain proper
operation of the unit. Elimination of contamination and remov-
al 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-metal-
lic 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 wa-
ter 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 ve-
locity 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 Carrier Replacement Components Division as
part number P902-0301 for a one gallon container, and part
number P902-0305 for a 5 gallon container. It is recommended
that all coils, including standard aluminum, pre-coated, copper/
copper or e-coated coils be cleaned with the Totaline environ-
mentally 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
WARNING
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this warning could result in personal injury,
death, and/or equipment damage.
This system uses Puron
®
refrigerant which has higher
pressures than R-22 and other refrigerants. No other
refrigerant may be used in this system. Gage set, hoses, and
recovery system must be designed to handle Puron
refrigerant. If unsure about equipment, consult the equipment
manufacturer.
Содержание Puron R-410A
Страница 29: ...29 Fig 44 RTU Open Overlay for Economizer Wiring ...
Страница 30: ...30 Fig 45 VFD Overlay for W2770 Controller Wiring ...
Страница 50: ...50 Fig 63 50KC Typical Unit Wiring Diagram Power 06A 208 230 3 60 ...
Страница 51: ...51 Fig 64 50KC Unit Wiring Diagram Control A06 ...
Страница 76: ...76 Fig B Unit Wiring Diagram Controls for Sizes A04 A06 208 230 1 60 208 230 3 60 460 3 60 575 3 60 ...
Страница 77: ...77 Fig C Unit Wiring Diagram Power for Sizes A04 and A06 208 230 1 60 ...
Страница 78: ...78 Fig D Unit Wiring Diagram Power for Size A05 208 230 1 60 ...
Страница 79: ...79 Fig E Unit Wiring Diagram Power for Sizes A04 A06 208 230 3 60 460 3 60 575 3 60 ...
Страница 80: ...80 APPENDIX F MOTORMASTER SENSOR LOCATIONS Fig F 50KC A04 Outdoor Circuiting Fig G 50KC A05 Outdoor Circuiting ...
Страница 81: ...81 Fig H 50KC A06 Outdoor Circuiting ...