Air-to-water Heat Pump
31
MONOBLOC
TYPE
Pressure Meter
Vacuum pump
Connection Pipe
Note
when vacuuming is nished, pressure inside the unit should be kept lower than 80Pa for at least 30 minutes to 
make sure there is no leak. Either charging valve 1 or charging valve 2 can be used for vacuuming.
Charging
: when vacuuming is nished and it is certain that there is no leak, charging can be done.
Leak Detection Methods
:
The following leak detection methods are deemed acceptable for systems containing ammable refrigerants.
Electronic leak detector shall be used to detect ammable refrigerant, but the sensitivity may not be adequate,
or may need re-calibration(Detection equipment shall be calibrated in a refrigerant-free area).
Ensure that the detector is not a potential source of ignition and is suitable for the refrigerant used.
Leak detection equipment shall be set at a percentage of the LFL of the refrigerant and shall be calibrated to the
refrigerant employed and the appropriate percentage of gas (25% maximum) is conrmed.
Leak detection uids are suitable for us with most refrigerant but the use of detergents containing chlorine shall 
be avoided as the chlorine may react with the refrigerant and corrode the copper pipe-work.
If a leak is suspected, all naked flames shall be removed / extinguished. If a leakage of refrigerant is found 
which requires brazing, all of the refrigerant shall be recovered from the system, or isolated (by means of shut off 
valves) in a part of the system remote from the leak. Oxygen free nitrogen (OFN) shall then be purged through the 
system  both before and during the brazing process.
Note
Before and during operation, use an appropriate refrigerant leak detector to monitor the operation area and 
make sure the technicians can be well aware of any potential or actual leakage of inammable gas. Make sure the 
leak detecting device is applicable to inammable refrigerant. For example, it should be free of sparks, completely 
sealed and safe in nature.
16. Installation of Insulated Water Tank 
16.1 Installation measure
The insulated water tank should be installed and keep levelly within 5m and vertically within 3m from the indoor 
unit. It can be installed in the room.
Standing water tank must be installed vertically with the bottom on the ground, never suspended. Installation 
place must be rm enough and the water tank should be xed on the wall with bolts to avoid vibration, as shown in 
the following gure. Weight capacity of water tank during installation should also be considered.