Midea MPPB-14CRN7, Instruction Manual

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exposed while charging, recovering or purging the system;
That there is continuity of earth bonding.
7.Repairs to sealed components
1)During repairs to sealed components, all electrical
supplies shall be disconnected from the equipment being
worked upon prior to any removal of sealed covers, etc. If it
isabsolutely necessary to have an electrical supply to
equipment during servicing, then a permanently operating
form of leak detection shall be located at the most critical
point to warn of a potentially hazardous situation.
2)Particular attention shall be paid to the following to ensure
that by working on electrical components, the casing is not
altered in such a way that the level of protection is affected.
This shall include damage to cables, excessive number of
connections, terminals not made to original specification,
damage to seals, incorrect fitting of glands, etc.
Ensure that apparatus is mounted securely.
Ensure that seals or sealing materials have not degraded
such that they no longer serve the purpose of preventing the
ingress of flammable atmospheres. Replacement parts shall
be in accordance with the manufacturer's specifications.
NOTE: The use of silicon sealant may inhibit the
effectiveness of some types of leak detection
equipment. Intrinsically safe components do not have to
be isolated prior to working on them.
8.Repair to intrinsically safe components
Do not apply any permanent inductive or capacitance
loads to the circuit without ensuring that this will not
exceed the permissible voltage and current permitted for
the equipment in use. Intrinsically safe components are
the only types that can be worked on while live in the
presence of a flammable atmosphere. The test apparatus
shall be at the correct rating. Replace components only
with parts specified by the manufacturer. Other parts may
result in the ignition of refrigerant in the atmosphere from
a leak.
9.Cabling
Check that cabling will not be subject to wear, corrosion,
excessive pressure, vibration, sharp edges or any other
adverse environmental effects. The check shall also take
into account the effects of aging or continual vibration
from sources such as compressors or fans.
10.Detection of flammable refrigerants
Under no circumstances shall potential sources of ignition
be used in the searching for or detection of refrigerant
leaks. A halide torch (or any other detector using a naked
flame) shall not be used.
11.Leak detection methods
he following leak detection methods are deemed
acceptable for systems containing flammable refrigerants.
Electronic leak detectors shall be used to detect flammable
refrigerants, but the sensitivity may not be adequate, or
Other tips
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