York YPAL 050 User Manual

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JOHNSON CONTROLS
FORM 100.50-NOM6 (1207)
Disconnect and lock-out power from 
the unit anytime service is being per-
 formed on the fan sec tion. Failure to 
do so could result in serious in ju ry or 
death due to the fan turning on while 
work is in progress.
Fan Motor
  1. Shut off unit power and lock out.
  2. Disconnect and tag power wires at motor 
   terminals.
 3. Loosen motor base-to-mount ing-rail at tach ing 
bolts.
 4. Mark belt as to position. Re move and set aside 
belts.
  5. Remove motor bracket hold down bolts.
  6. Remove motor pulley and set aside.
 7. Remove motor.
  8.  Install  new  motor.  Re as sem ble  by  re vers ing  steps 
1 - 6. Be sure to re in stall  mul ti ple  belts  in  their 
orig i nal po si tion. Use a complete new set if re-
 quired. Do not stretch belts over sheaves. Re view 
the sec tions on motor and sheave in stal la tion, 
sheave align ment, and belt tensioning discussed 
pre vi ous ly.
  9. Reconnect motor leads and restore power. Check 
fan for proper ro ta tion as described in Start-Up 
Check List.
Fan Shaft Bearings
General – When removing and replacing the bearings, 
care should be taken to en sure that the area where the 
bear ings  fi t on the shaft does not be come scored or 
dam aged. The shaft in this area should be thoroughly 
cleaned before the bearing is removed and again be fore 
the new bear ing is installed.
Mounting Details –
  1. Check the shaft - it should be straight, free of burrs 
and full size. Be sure the bearing is not seated on 
a worn section of shafting.
 2. Make certain any set screws are not ob struct ing 
the bearing bore.
  3. Align the bearing in its hous ing and slide the bear-
 ing into position on shaft - never hammer the ends 
of the inner race. If nec es sary, use a brass bar or 
pipe against the inner race to drift bearing into 
place - never hit the housing, as bearing dam age 
may re sult. Make sure there is lu bri cant  between 
the bear ing outer ring and the hous ing.
  4. Fasten the bearing housing to the unit mount ing 
sup port with hex head cap screws, wash ers, new 
lock wash ers and hex nuts before se cur ing  the  bear-
ing to the shaft. This permits the bearing to align 
itself in po si tion along the shaft and eliminates any 
pos si bil i ty  of  cramp ing loads.
  5. Rotate the shaft to make cer tain it turns free ly.
 6. Bearings may employ one of several different 
meth ods to lock the bear ing to the shaft.
Shaft should be free from burrs. If old 
shaft is used, be sure a ball bearing is 
not seat ed on worn section and shaft 
is not bent.
There are various degrees of self-alignment in bear ings 
of the same man u fac tur er.  The  force  required  for  the 
self-alignment of the bear ings used in JOHNSON 
CONTROLS man u fac tured units has been spec i fi ed 
and is close ly monitored at the fac to ry. If it is nec es sary 
to purchase a bearing locally, be sure it can be worked 
around in the housing with a short shaft made of wood 
or other soft material placed in the bearing.