McQuay IM 987
107
Maintenance
Cabinet Sections
Once a month, open a door on each section and verify that no
moisture or debris is accumulating in the unit.
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.
Using the following procedure, relubricate the bearings while
the motor is warm, but not running. Use one of the greases
shown in
Table 16
.
1
Remove and clean upper and lower grease plugs.
2
Insert a grease fitting into the upper hole and add clean
grease (
Table 16
) 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.
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. See below for specific recommended
lubricants.
Table 16: Recommended Lubricants and Amounts for Fan
Motor Bearings
Mfr. Grease
NEMA Size
Amount to
Add (oz.)
Texaco,
Polystar
or
Polyrex EM
(Exxon Mobile)
or
Rykon
Premium #2
or
Penzoil Pen 2
Lube
56 to 140
0.08
140
0.15
180
0.19
210
0.30
250
0.47
280
0.61
320
0.76
360
0.81
400
1.25
440
2.12