Leak Detection and Automatic Refrigerant Pump Down

Improving Safety and the Environment
Panasonic has developed an innovative solution to detect refrigerant leaks that offer complete assurance and protection for end users, building occupiers and the environment. Panasonic’s Pump Down System is ideal for hotels, offices and public buildings where safety for occupants and the building owners is of utmost importance.
The system monitors refrigerant leakage continually and provides a warning before refrigerant leaks, preventing major refrigerant loss and potentially damaging the system’s efficiency.  The new system can improve potential refrigerant loss to approximately 90%.
As well as ensuring safe and reliable operation, Panasonic’s Pump Down System contributes to a building qualifying for additional BREEAM points and enables compliance with current EN378 2008 standards, covering applications where refrigeration concentration levels exceed practical safety limits of 0,44 kg/m³.
Panasonic has developed two detection methods that can operate simultaneously to offer complete protection for owners, building occupiers and the environment.
Pump Down System
This innovative pump down system can be connected in two ways:
  • With sensor leakage
  • Without sensor leakage, using only the innovative algorithme.

Basic pump down function:
  • Detect the leakage
  • Activate pump down process
  • Collect the gas on the tank
  • Close the valves to isolate the gas

Key points:
  • Comply with legislation
  • Protect personnel
  • Protect the environment
  • Save on operating costs
Panasonic offers a purposely engineered solution which allows for a quick and simple installation. The unit contains 5 actuating ball valves, a 30l storage vessel and PLC all housed in an IP54 rated container. Terminals on the front of the unit allow for easy wiring to the alarm terminal, high / low pressure transducers and discharge temperature sensor(s) of the condensing unit(s).
Direct Leak Detection Method: The Safest Solution for Small Rooms
This option should be implemented in any area in non-compliance with BS EN 378:2008. The leak detector is connected directly to the indoor unit via the dedicated PAW-EXCT connector and the Pump Down System is directly connected to the outdoor unit PCB.
The Pump Down System will activate when a leak is detected in the room and initiate a refrigerant reclaim operation immediately, the refrigerant will be collected inside the outdoor units’ heat exchanger and optional receiver tank for larger systems.
This immediate reaction and large refrigerant storage capacity offers very high level of safety for end users, building occupiers as well as being environmentally friendly.
Due to the exclusive ECOi software the leak detection sensors are able to communicate directly via the P-link which means no additional communication panels, cabling or software is required.

1. Signal. 2. Leakage! 3. Room 1. 4. Room 2. 5. Leak detector.

In-Direct Leak Detection Method: Unique PLC Algorithm to Determine Refrigerant Leakage

Pressure and temperature sensors constantly monitor the low / high pressure and discharge of the condensing unit to protect against potential leakage in areas not covered by leak detectors. If low pressure decreases and compressor discharge temperature increases at pre-defined values according to a pre-set algorithm then the unit will trigger a pump down sequence.
The new innovative algorithm is able to detect leakage of R410A based on abnormal changes in the following conditions, high pressure, low pressure and compressor discharge temperature.
Once initiated via either direct or in-direct detection, the unit will immediately close the liquid / discharge actuating ball valves close the alarm terminals on the Pump Down PCB allowing an alarm to be raised at any nominated location.
Reclaim of the refrigerant is via the suction line to the heat exchanger(s) of the outdoor unit(s), any surplus refrigerant is collected in the 30l receiver tank. Once fully pumped down the suction line is closed and the unit awaits a ‘Reset’ and ‘Recharge’ command.
Due to the simplistic installation and control interfacing, shown in Fig 1, Panasonic’s ECOi Pump Down System can provide dramatic reduction in capital cost and installation time when compared to a standalone leak detection system, shown in Fig 2. This option is ideal for hotels, offices and public buildings where safety of building occupiers is a must and is extremely cost effective, savings of 40% can be easily achieved.
ECOi 2-Pipe
PAW-PUDME1A-1: Pump down for 1 outdoor unit system
PAW-PUDME1A-2: Pump down for 2 outdoor units system
PAW-PUDME1A-3: Pump down for 3 outdoor units system
PAW-PUDME1A-1R: Pump down for 1 outdoor unit system + Receiver Kit 30l
PAW-PUDME1A-2R: Pump down for 2 outdoor units system + Receiver Kit 30l
PAW-PUDME1A-3R: Pump down for 3 outdoor units system + Receiver Kit 30l
ECOi 3-Pipe
PAW-PUDMF2A-1: Pump down for 1 outdoor unit system
PAW-PUDMF2A-2: Pump down for 2 outdoor units system
PAW-PUDMF2A-3: Pump down for 3 outdoor units system
PAW-PUDMF2A-1R: Pump down for 1 outdoor unit system + Receiver Kit 30l
PAW-PUDMF2A-2R: Pump down for 2 outdoor units system + Receiver Kit 30l
PAW-PUDMF2A-3R: Pump down for 3 outdoor units system + Receiver Kit 30l

Accessory (common)
PAW-PUDRK30L: Receiver Kit 30l