McQuay RoofPak RAH 047C, Руководство по установке и обслуживанию

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106 McQuay IM 487-4
Maintenance
preventive compound. Pay close attention to fan shafts,
sheaves, bearings, and bearing supports,
Cabinet Sections
Once a month, open a door on each section and verify that no
moisture or debris is accumulating in the unit.
Cooling circuits
The steps below are necessary only if the unit has been started.
1
Provide that each circuit is properly pumped down.
2
Pull the fuses to each compressor (store them in the control
cabinet)
3
Close all the refrigerant service valves on each circuit
4
Tag the valves as a warning for the technician who restarts
the units
Gas Furnace
If the unit is equipped with a gas furnace, close the gas shutoff
valve and open furnace control switch S3.
Control Compartment
1
McQuay International recommends that the electronic
control equipment in the unit be stored in a 5% to 95% RH
(non-condensing) environment.
2
It may be necessary to put a heat source (light bulb) in the
main control panel to prevent the accumulation of
atmospheric condensate within the panel.
3
The location and wattage of the heat source is dependent on
local environmental conditions.
4
Check the control compartment every two weeks to provide
that the heat source is functional and is adequate for current
conditions.
Restart
After extended storage, perform a complete start up. Inevitable
accumulations of dirt, insect nests, etc. can contribute to
problems if not cleaned out thoroughly prior to start up. In
addition, thermal cycling tends to loosen mechanical and
electrical connections. Following the startup procedure helps
discover these and other issues that may have developed
during the storage interval.
Gas Furnace
For information on maintenance of the gas furnace, refer to
Bulletin No. IM 684 or IM 685.
Bearing Lubrication
Motor Bearings
Supply and return fans —Supply and return fan motors
should have grease added after every 2000 hours of operation.
Use one of the greases shown in Table 16 on page 106. Using
the following procedure, relubricate the bearings while the
motor is warm, but not running.
1
Remove and clean upper and lower grease plugs.
2
Insert a grease fitting into the upper hole and add a small
amount of clean grease with a low pressure gun.
3
Run the motor for five minutes before replacing the plugs.
Note:
Specific greasing instructions are located on a tag
attached to the motor. If special lubrication instructions
are on the motor, they supersede all other instructions.
Fan Shaft Bearings
Relubricate fan shaft bearings periodically. Relubricate
according to the schedule shown in Table on page 106. If the
bearings are exposed to wet conditions, wide temperature
variations, or other severe atmospheric conditions, relubricate
more frequently. Use one of the greases shown in Table 16.
While the bearing is at normal operating temperatures, rotate
the fan by hand and add only enough grease to purge the seals.
The seals bleed slightly when this occurs. Do not
overlubricate.
CAUTION
Bearing overheating potential. Can damage the equipment.
Do not overlubricate bearings.
Use only a high grade mineral grease with a 200°F safe
operating temperature. Refer to Table on page 106 for specific
recommended lubricants.
Table 16: Recommended greases
Manufacturer Product name Temp. range (°F)
Texaco Lubricants Co. Premium RB -30 to 300
Keystone Ind. Lubricants 84EP-2 -40 to 200
Mobil Oil Corporation Mobilith AW2 -40 to 325
Chevron U.S.A. Inc. SRI-2 -20 to 325
Exxon Company. U.S.A. Ronex MP -40 to 300
Shell Oil Company Alvania No. 2 -20 to 240
Table 17: Recommended fan shaft bearing lubrication
intervals
Operating duty
Bearing ambient temperature
To 130°F To 150°F Over 150°F
Continuous 6 months 4 months 2 months
12 Hrs./Day 12 months 12 months 6 months
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