Evaporator Fan Service and Replacement -- _e
48PC units feature a slide-out fan deck for easy servicing of the
indoor-fan motor, pulleys, belt, and beatings. To service com-
ponents in this section, perform the following procedme:
1. Tumoffunit powel:
2. Open file fan section access dooc
3. Remove two no. 10 screws fit fiont of slide-out fan deck.
Save screws. See Fig. 27.
4. Disconnect the electrical wires connected to the slide-out
fan deck (supply air thermistor and fan status switch if
installed). Wires may be &tmaged if not disconnected.
5. Fan deck can now be slid out to access serviceable
components.
7. Return fan deck back into operating position.
8. Restore power to unit.
Condenser-Fan Adjustment (Fig. 29)
1. Shut off unit power supply.
2. Remove condenser-fan assembly (grille, motor, motor
cover, and fan) and loosen fan hub setscrews.
3. Adjust fan height as shown in Fig. 29.
4. Tighten setscrews and replace condenser-fan assembly.
5. Turn on powerto unit.
MOTOR
FAN DECK
STOP
DO NOT SLIDE FAN DECK OUT PAST THE FAN
DECK STOR If further access is required, the fan deck
must be supported. Make sine plugs and wiring are not
pinched between fan housing find unit sheet metal post.
Damage to unit may result.
6. To replace fan deck to operating position, slide fan deck
back into the unit. Secure with the two no. 10 screws re-
moved in Step 3.
7. Re-attach electrical wires.
8. Close fan section access dool:
9. Restore power to unit.
Evaporator Fan Performance Adjustment
(Fig. 27 and 28) -- Fan motor pulleys fu'e factory set
for speed shown in Table 33.
To change fan speeds:
1. Shut off unit power supply.
2. Loosen nuts on the 4 carriage bolts in the mounting base.
Using adjusting bolts and plate, slide motor find remove
belt.
3. Loosen movable-pulley flange setscrew (see Fig. 28).
4. Sclew movable flange toward fixed flange to increase
speed and away from fixed flange to decrease speed.
Increasing fan speed incleases load on motol: Do not ex-
ceed maximum speed specified in Table 33.
See Table 31 for air quantity limits.
5. Set movable flange at nemest keyway of pulley hub find
tighten setscrew. (See Table 33 for speed change for each
full turn of pulley flange.)
6. Replace belts.
7. Realign fan find motor pulleys:
a. Loosen fan pulley setscrews.
b. Slide fan pulley along fan shaft.
c. Make angular alignment by loosening motor from
mounting plate.
8. Tighten belts.
9. Restole power to unit.
Evaporator Fan Belt Tension Adjustment -- To
adjust belt tension:
1. Turnoffunit powel:
2. Slide out fan deck to service position as shown in Evapo-
rator Fan Selwice and Replacement section above.
3. Loosen motor mounting plate bolts.
4. Move motor mounting plate to adjust to proper belt ten-
sion. Motor adjuster bolts may be used to tighten belts.
See Fig. 27. Do not overtighten belt.
5. Check for proper belt fflignment. Adjust if necessmy.
6. Tighten motor mounting plate bolts to lock motor in
proper position.
MOUNTING
BASE
SCREW
(HIDDEN)
FAN
PULLEY
PULLEY
SCREW
SLIDE-OUT
FAN DECK
Fig. 27 -- Evaporator-Fan Motor Adjustment
PULLEY
PULLEY
STRAIGHTEDGE MUST
WITH BELT
MOTOR AND FAN
SHAFTS MUST BE
PARALLEL
MOVABLE
FLANGES
SETSCREWS_
FIXED FLANGES
SINGLE-GROOVE
Fig. 28 -- Evaporator-Fan Alignment and
Adjustment
Fig. 29 -- Condenser-Fan Adjustment
39
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