23
Remedy
In case there is leakage of refrigerant from the system ,do not hurry to
recharge it with refrigerant ,manage to find out leak points immediately ,and
make a note of from where it leaks ---welding points and parts .After having
them repaired ,recharge refrigerant .
There
are
so
many
joints
and
sealed
surfaces
in
a
refrigerator
,accordingly
,quite
a
lot
potential
leak
points
do
exist in the
system .In
troubleshooting
,pay
attention
to
those
parts
that
are
liable to
leak ,check
main
connection
points
for
oil
seepage
and
tubing
for
cracks .If
there is no
severer
leak
point
,charge
the
system
with
nitrogen
and detect
leak
points
with
the
commonly
adopted
method
,repair
them ,evacuate
,charge
the
system
with
refrigerant
,and
then
turn on the
refrigerator to make a test run .
2) Too much refrigerant charged into the system
Analysis of Trouble
a) In
case
the
amount
of
refrigerant
charged
into
the
system
exceeds
its nominal
capacity
,the
superfluous
refrigerant
will
of
course
take some
space of
the
evaporator
,thus
reducing
its
heat-dissipation
area
and hence
the refrigerating
efficiency
of
the
system
.The
abnormal
phenomena
caused by
this
reason
are
as
follows
:the
gas
suction
and
exhaust
pressures
are
generally
higher
than
their
respective
normal
values ,the
temperature
of
its
condenser
is
higher
and
the
electric
current of the
compressor
rises
,loose
frost
forms
on
the
evaporator
,the
refrigerator
temperature drops slowly
,and frost appears on the gas return tube .
b) In
case
excessive
refrigerant
has
been
charged
,the liquid
refrigerant
that
cannot
evaporates
in
the
evaporator
will
return to the
compressor
,and
thus
a
phenomenon
of "liquid
striking
will
occur .The
liquid refrigerant
evaporates
and
affects
as
soon
as
it
flows
into the
refrigerating
oil
at
the
bottom
of
compressor
.If
the
condition is
severe ,foams
will
fill
all
over
inside
the compressor housing
and
be sucked
by the piston ,causing damage to the components
of compressor .
Remedy
According
to
the
operating
procedures
,it
is
mandatory
to
turn the
machine
OFF
,and
several
minutes
later
,open
the
refrigerant
charging tube
and let the
refrigerant
escape from
it
,replace
the
dry
filter
,recharge
refrigerant after evacuating ,and then seal the charging port .
3) There is air left in the refrigerating system
Analysis of Trouble
Residual
air
in
the
refrigerating
system
will
reduce
its
refrigerating
efficiency .The prominent phenomena are the increase in its gas suction
and exhaust pressures (however ,the gas exhaust pressure will not exceed
its rated value ),obvious increase in temperature in the segment from the
compressor outlet to the condenser inlet .Because there is air in the
system ,both the gas exhaust pressure and temperature will rise ,and
Summary of Contents for HRB-271
Page 15: ...CIRCUIT DIAGRAM 14 ...
Page 36: ...36 ...
Page 37: ...37 ...
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