A
PD MANUAL
IOM-39
33 of 36
Aug 99 R1
HEATING
Follow
maintenance
procedures
for
applicable
Pack,
DJ(E),
DG,
RT,
HE
,
LM
‐
K
electric
heat
section
etc.
REFRIGERATION
Seasonal
Maintenance
1.
On
semi
‐
hermetic
and
screw
compressors,
check
compressor
oil
level
and
add
refrigerant
oil
if
necessary.
2.
Check
operating
temperature
and
pressures.
3.
On
units
with
sight
glasses,
check
for
leaks.
There
should
be
no
foaming
under
steady
state
operation.
Condensing
Section:
Water
Cooled
‐
With
time,
condensers
can
foul
with
mineral
deposits
from
the
water,
resulting
in
a
reduced
heat
transfer
capacity
and
increased
refrigerant
head
pressure.
Should
this
condition
occur,
the
condenser
coil
should
be
chemically
cleaned
or
replaced.
Air
Cooled
–
The
external
surface
of
finned
coils
can
be
cleaned
using
a
low
pressure
water
spray
and
a
brush.
Coil
fins
are
easily
damaged.
Do
not
use
high
pressure
steam
or
water
to
clean
coils;
it
will
permanently
damage
the
coil.
When
using
cleaning
additives
or
solutions
they
must
be
compatible
with
the
coil
materials
or
coatings.
Use
a
fin
comb
to
straighten
any
damaged
or
bent
fins.
1.
Inspect
refrigerant
lines
for
evidence
of
oil
leaks.
2.
Check
condenser
fans
and
tighten
set
screws.
NOTE:
Air
flow
is
restricted
by
dirty
coils,
dirty
filters,
slipping
fan
belts
etc.
This
will
reduce
cooling
capacity
and
coil
frosting
can
occur.
