Trane GRCA - Page 26

PROBLEM
PROBABLE CAUSE SOLUTION
3.
Motor runs and then
Partial loss of line voltage. Check
for
loose
connections.
dies down.
Determine
adequacy
of
main power supply.
4 .
Motor
does
not
come up to speed .
M oto r unders i zed f o r
application.
Voltage too l
o
w
a
t m
o
t
o
r terminals.
Line wiring to motor
is t
oo
small.
Replace with larger motor.
Check across AC
line
and
correct if possible.
Install larger line wiring.
5. M o t o r t akes t oo l ong
E
xce
s
sive l
oa d .
R eplace
with
l arge r
mo t or.
to acce l
erate.
L oose connec
ti
o
n . C hec k con n
ectio
n s a
nd t ig h te n whe r e n ecessary.
6.
Wr ong R otatio n (3 P hase) Improperly
wired t
o
AC line (wrong Chec k u ni t wiring
diagra
m . R
everse
a
n y t wo line
sequence o
f phases). voltage co n
nections.
7. M otor Ove r hea
t
s
8 .
Motor
Vibrates
Motor
overloaded. Replace
with
larger
motor.
Motor
ventilation clogged. Clean
motor.
M oto
r (
3 p
h
ase)
m
ay
h
a
ve open phase. Ch ec k t o insure
that al l con n ectio n
s
are tight.
Li n e vol t age too high or t oo l ow. Chec
k across AC line and co r rect if p
ossib l
e.
Worn blower bearings.
Replace blower bearings.
Motor mounting bolts loose. Tighten mounting
bolts.
Driven equ
ip
ment u
n
ba
l
anced.
B
a
lanc
e d
riven
eq
uipment.
Worn motor bearings. Replace motor.
3 phase Motor
running
on
single
phase.
Check for open circuit and
correct.
B en t
motor
shaf t .
Replace motor.
9.
R apid Motor B
ea r in g
Excessive overhung l
oa d due
t o ove r R ed u ce belt
tensio
n .
W ear t ensioned belt.
TROUBLESHOOTING GUIDE
FAN ASSEMBLY
PROBLEM
PROBABLE
CAUSE SOLUTION
1. Sho r t
Belt
Li f e Spin b urns from belt slip p age. T ens
i
on belt.
High ambient temperature. Use Gripnotch
belts.
Grease or o
i l
on be
lt
s. C
l
ea
n
be
l t
s a
n
d pu
lley
s.
W or n pu
l
leys. R e p lace pu
ll
eys.
B
el
t M isalign m en t . R eal i g n drive.
2. Belts turn
over in grooves Damaged belt.
Excessive vib r
a
ti
o
n.
Worn pulleys.
Pulley
Misalignment.
Replace belt.
Tension belts. Replace
belts if damaged.
Replace pulleys.
Realign
drive.
3.
B
elt Squeal Excessive l
oad.
Hig
h s
t
a
rting
load.Retension
drive.
4. Belt Breakage
Foreign material in drive. Provide drive guard.
Belts damaged during installation. Replace
be
lt
s.
E x t reme Overload. E li m inate over l oad.
5. E xcessive V
i b
ratio
n Damaged be l t cord section. R ep l ace b e
l ts.
L oose belts. T e n s i o n drive.
Belts improperly tensioned.
Tension drive
with slack of each belt on the
same side of drive.
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