Heat Pump
Unitherm 3 R32
49
Malfunctions
Reasons
Troubleshooting
Poor efficiency of hot water
heating
Poor heat insulation of water system.
Poor heat exchange of evaporator.
Poor refrigerant of unit.
Blockage of heat exchanger at water
side.
Enhance heat insulation efficiency of the
system.
Check if air in or out of unit is normal and
clean evaporator of the unit.
Check if refrigerant of unit leaks.
Clean or replace heat exchanger.
21.1 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 working 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.
21.2 Decommissioning
Before carrying out this procedure, it is essential that the technician is completely familiar with the equipment
and all its detail. 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 refrigerant 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.
