About The Product - Fujitsu AIR CONDITIONER Installation Manual

Outdoor unit with r32 refrigerant
Hide thumbs Also See for AIR CONDITIONER:
Table of Contents

Advertisement

8.Removal and evacuation
When breaking into the refrigerant circuit to make repairs – or for any other
purpose –conventional procedures shall be used.
However, it is important that best practice is followed since flammability is a consid-
eration.
The following procedure shall be adhered to:
remove refrigerant
purge the circuit with inert gas
evacuate
purge again with inert gas
open the circuit by cutting or brazing
The refrigerant charge shall be recovered into the correct recovery cylinders.
The system shall be "flushed" with OFN to render the unit safe.
This process may need to be repeated several times.
Compressed air or oxygen shall not be used for this task.
Flushing shall be achieved by breaking the vacuum in the system with OFN and
continuing to fill until the working pressure is achieved, then venting to atmosphere,
and finally pulling down to a vacuum.
This process shall be repeated until no refrigerant is within the system.
When the final OFN charge is used, the system shall be vented down to atmos-
pheric pressure to enable work to take place.
This operation is absolutely vital if brazing operations on the pipe work are to take
place.
Ensure that the outlet for the vacuum pump is not close to any ignition sources and
there is ventilation available.
9.Charging procedures
In addition to conventional charging procedures, the following requirements shall be
followed.
- Ensure that contamination of different refrigerants does not occur when using
charging equipment.
- Hoses or lines shall be as short as possible to minimize the amount of refrigerant
contained in them.
- Cylinders shall be kept upright.
- Ensure that the refrigeration system is earthed prior to charging the system with
refrigerant.
- Label the system when charging is complete (if not already).
- Extreme care shall be taken not to overfill the refrigeration system.
Prior to recharging the system it shall be pressure tested with OFN.
The system shall be leak tested on completion of charging but prior to commission-
ing.
A follow up leak test shall be carried out prior to leaving the site.
10.Decommissioning
Before carrying out this procedure, it is essential that the technician is completely
familiar with the equipment and all its details.
It is recommended good practice that all refrigerants are recovered safely.
Prior to the task being carried out, an oil and refrigerant sample shall be taken in
case analysis is required prior to re-use of reclaimed refrigerant.
It is essential that electrical power is available before the task is commenced.
a) Become familiar with the equipment and its operation.
b) Isolate system electrically.
c) Before attempting the procedure ensure that:
mechanical handling equipment is available, if required, for handling refriger-
ant cylinders;
all personal protective equipment is available and being used correctly;
the recovery process is supervised at all times by a competent person;
recovery equipment and cylinders conform to the appropriate standards.
d) Pump down refrigerant system, if possible.
e) If a vacuum is not possible, make a manifold so that refrigerant can be removed
from various parts of the system.
f) Make sure that cylinder is situated on the scales before recovery takes place.
g) Start the recovery machine and operate in accordance with manufacturer's
instructions.
h) Do not overfill cylinders. (No more than 80 % volume liquid charge).
i) Do not exceed the maximum working pressure of the cylinder, even temporarily.
j) When the cylinders have been filled correctly and the process completed, make
sure that the cylinders and the equipment are removed from site promptly and
all isolation valves on the equipment are closed off.
k) Recovered refrigerant shall not be charged into another refrigeration system
unless it has been cleaned and checked.
11.Labelling
Equipment shall be labelled stating that it has been de-commissioned and emptied
of refrigerant.
The label shall be dated and signed.
Ensure that there are labels on the equipment stating the equipment contains flam-
mable refrigerant.
R32_outdoor_2版_01_EN.indd
3
12.Recovery
When removing refrigerant from a system, either for servicing or decommissioning,
it is recommended good practice that all refrigerants are removed safely.
When transferring refrigerant into cylinders, ensure that only appropriate refrigerant
recovery cylinders are employed.
Ensure that the correct number of cylinders for holding the total system charge are
available.
All cylinders to be used are designated for the recovered refrigerant and labelled for
that refrigerant (i.e. special cylinders for the recovery of refrigerant).
Cylinders shall be complete with pressure relief valve and associated shut-off valves
in good working order.
Empty recovery cylinders are evacuated and, if possible, cooled before recovery
occurs.
The recovery equipment shall be in good working order with a set of instructions
concerning the equipment that is at hand and shall be suitable for the recovery of
flammable refrigerants.
In addition, a set of calibrated weighing scales shall be available and in good work-
ing order.
Hoses shall be complete with leak-free disconnect couplings and in good condition.
Before using the recovery machine, check that it is in satisfactory working order, has
been properly maintained and that any associated electrical components are sealed
to prevent ignition in the event of a refrigerant release.
Consult manufacturer if in doubt.
The recovered refrigerant shall be returned to the refrigerant supplier in the correct
recovery cylinder, and the relevant Waste Transfer Note arranged.
Do not mix refrigerants in recovery units and especially not in cylinders.
If compressors or compressor oils are to be removed, ensure that they have been
evacuated to an acceptable level to make certain that flammable refrigerant does
not remain within the lubricant.
The evacuation process shall be carried out prior to returning the compressor to the
suppliers.
Only electric heating to the compressor body shall be employed to accelerate this
process.
When oil is drained from a system, it shall be carried out safely.
Explanation of symbols displayed on the indoor unit or outdoor unit.
This symbol shows that this equipment uses a flammable
refrigerant.
WARNING
If the refrigerant is leaked, together with an external igni-
tion source, there is a possibility of ignition.
This symbol shows that the Operation Manual should be
CAUTION
read carefully.
This symbol shows that a service personnel should be
CAUTION
handling this equipment with reference to the Installation
Manual.
This symbol shows that there is information included in the
CAUTION
Operation Manual and/or Installation Manual.
2. ABOUT THIS PRODUCT
2.1. Special tools for R32 (R410A)
Tool name
Change from R22 to R32(R410A)
Pressure is high and cannot be measured with a conven-
tional (R22) gauge. To prevent erroneous mixing of other
Gauge manifold
refrigerants, the diameter of each port has been changed.
It is recommended to use gauge with seals -0.1 to 5.3 MPa
(-1 to 53 bar) for high pressure.
-0.1 to 3.8 MPa (-1 to 38 bar) for low pressure.
To increase pressure resistance, the hose material and base
Charge hose
size were changed.(R32/R410A)
A conventional vacuum pump can be used by installing a
Vacuum pump
vacuum pump adapter.
(Use of a vacuum pump with a series motor is prohibited.)
Special gas leakage detector for HFC refrigerant R32 or
Gas leakage detector
R410A.
Copper pipes
It is necessary to use seamless copper pipes and it is desirable that the amount of residual
oil is less than 40 mg/10 m. Do not use copper pipes having a collapsed, deformed or
discolored portion (especially on the interior surface). Otherwise, the expansion value or
capillary tube may become blocked with contaminants.
As an air conditioner using R32(R410A) incurs pressure higher than when using R22, it is
necessary to choose adequate materials.
Thicknesses of copper pipes used with R32(R410A) are as shown in Table1. Never use
copper pipes thinner than 0.8 mm even when it is available on the market.
Thicknesses of Annealed Copper Pipes
Nominal diameter (in.)
Outer diameter (mm)
1/4
6.35
3/8
9.52
1/2
12.70
Thickness (mm)
0.80
0.80
0.80
En-3
2013/07/05
20:50:05

Hide quick links:

Advertisement

Table of Contents
loading

Table of Contents