5. Maintenance
1110
5.1 Precaution
of
maintenance
for
units
with
flammable
refrigerant
1)
Requirement
about
service
area
and
person
Service persons and all other people at site should be well awared about character of maintenance to
be carried out
.
Make sure the service area is not inclosed and keep good ventilation
(
opening doors and
windows
).
Service area should be properly isolated
.
And
ensure the safety of working conditions in
service area by controlling the combustible materials.
Monitor
status
of
refrigerant
Before or during the service operation
,
monitoring device is required to keep checking status of
refrigerant so that service persons can keep awared about existing combustible gas
.
2)
3)
Storage
of
fire
extinguishers
When
hot-working
treatment
is
needed
for
heat pump system or related components, ensure
fire
extinguisher
is
placed
nearby.
The
proper
fire
extinguisher
should
be
type
of
dry powder or carbon
dioxide.
4)
Conduct safety inspections at service area
to
ensure
that
there
is no flames and potential ignition
sources (including smoke)
and
keep strict
control
in isolating
combustible
materials.
Prohibition of fire
Inspection
of
equipment
If electrical components are to be replaced, they should be installed in accordance with intended
use and correct operating regulations.
5)
6) Inspection of electrical elements
The service on
electrical
components
should
include
general
security
check
and
inspection of
electrical elements.
If
a defect that
could
threaten
personal
safety
is
found,
power
off
the
appliance
until
the
defect
is
properly
solved.
If
the
defect
can
not be completely eliminated while it ism a must
be continue the operation,
appropriate
temporary
solutions
should
be
well
adopted. Please report
the situation to owner of equipment
and
warn
all
relevant
personnels.
7) Inspection of cables
Check the status of cables and verify if any defects happen
because of abrasion,
corrosion,
overpressure,
vibration, cut
by
sharp
edges
or
other
reasons.
This
inspection
should
also
consider
the
effects
because
of cable aging and continuous vibration of compressor
and
the
fans.
8) Inspection of flammable refrigerants
Inspection of refrigerant leakage should be carried out in service area without fire or any other
potential ignition source
.
And this inspection should not be done by detectors working with ignition
,
such as halogen probe
.
If a leak is suspected, all flames should be removed from service area or
extinguished.
If soldering is required at leakage point
,
it is a must to recover all refrigerant or isolate it at somewhere
not close to leakage point
(
by service valve
).
Before or in process of soldering
,
oxygen-free nitrogen
(OFN)
should
be
used
in
order
to
purify
the
system.
