VRV-WII – Water-Cooled Condensing Unit

The Water-cooled VRV (VRV-WII) offers an energy-saving alternative to traditional centralized equipment. The VRV-WII is used extensively worldwide in skyscrapers where the use of a cooling tower and boiler are necessary. Its remarkable compact and lightweight structure makes installation of VRV technology in large buildings possible. At only 330 lbs. and less than 40” high, the VRV-WII can take a ride up the elevator to be installed in a machine room. It is a perfect fit for hotels and conference facilities, offices and universities, especially in urban-packed areas.

vrv-w2-01

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A water loop is necessary between the VRV-WII condensing units installed and a cooling tower and/or boiler.

The VRV-WII design is based on a “modular design” concept. It is composed of unified condensing units that require simply to connect a 2-Pipe Refrigerant Network for Heat Pump Applications or a 3-Pipe for Heat Recovery Applications. All Water Cooled Condensers are in the same cabinet, but are available in a variety of capacities (5-Ton, 6-Ton & 7-Ton). A simple system that allows manifolding together up to 3 Condensers to form one system of 21-Ton (252MBH). The condensers are designed for Internal mounting only.

Why selecting a VRV-WII system? The top 4 reasons that make the solution a perfect fit

  1. The efficiency and capacity of air cooled systems reduces with extreme ambient conditions causing systems to be oversized and increasing first cost.
  2. Extreme piping lengths cause a capacity reduction; positioning VRV-WII floor by floor can reduce the capacity reduction and improve the efficiency of the system. Also, long piping lengths cause a capacity reduction, positioning VRV-WII floor by floor can reduce the capacity reduction and improve the efficiency of the system
  3. Utilizing an existing condenser loop and associated heat rejection/injection will reduce first cost
  4. Where the building has diverse loads and energy can be recovered through the VRV-WII system and/or the water loop
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New construction

The VRV-WII provides an energy efficient solution anywhere that could use a water cooled chiller or replacing Water Source Heat Pump design by enabling them to afford the “water cooled chiller” benefits. It is especially true for high rise buildings such as:

  • Condos
  • Offices
  • In the northern climates, the VRV-WII eliminates the low ambient heating concern and the low ambient cooling concern
  • Large building tenant fit outs: with VRV-WII, the floors can now be leased as they are being completed in sequence.
  • Geothermal applications
  • Add on new build to existing campuses

Retrofit

The thought process seems to be Water Cooled is only suitable for large projects. Well, that’s not true anymore with the VRV-WII. The VRV-WII reveals itself very competitive when replacing noisy Water Source Heat Pump or rooftop with VAVs, allowing the owner to upgrade to a VRV-WII.Adding on to an existing water cooled system or to solve problem areas with VRV-WII becomes very easy, cost effective solutions for applications such as hospitals, Large business campus, universities, office buildings and factories.

Also, the VRV-WII can take advantage of an application with an existing 2 pipe chiller/boiler system on condenser water loop.

Strong advantage in large commercial job: Tenant fit out base build

  • VRV-WII Unified Condensing Unit – Heat Recovery or Heat Pump from One Unit.
  • Connect two pipes = Heat Pump
  • Connect three pipes + BS-boxes = Heat Recovery
  • The water loop can be designed for maximum anticipated installed load.

Benefits:

  • Lower initial cost for the developer/builder.
  • More flexibility for letting the building if the water loop is designed on the basis of a call center on each floor.
  • Client or developer can add air conditioning to match required load requirements.
  • No rebalancing of water systems if commissioning valves are installed on each floor.

 

SpecificationApplication Rules
Water Flow Rate13.2-39.5 gpm (49.9-149 l/m)
Water Temp Range Cooling60-113°F (15-45°C)
Water Temp Range Heating60-113°F (15-45°C)
Water Temp Range Stimultaneous Cooling & Heating60-113°F (15-45°C)
Glycol Allowance0-40%
Glycol Type Propylene/Ethylene
Connection Ratio
50(60)-130%

VVRV-WII connects to a closed loop cooling tower and boiler or in a Geothermal configuration

The VRV-WII (unified heat pump or heat recovery condensing unit) allows for continuous operation even in cold climate delivering comfortable heating performance with no defrost. The system’s brazed plate heat exchanger can tolerate water pressure up to 285 psi (or 640ft. of head) and has modular units that can be interconnected to make combinations of up to 21 tons. It is originally designed to operate with a closed loop cooling tower, dry cooler and boiler solutions.

SpecificationApplication Rules
Water Flow Rate21-26.4 gpm (80-100 l/m)
Water Temp Range Cooling50-113°F (10-45°C)
Water Temp Range Heating24.8-113°F (-4-45°C)
Water Temp Range Stimultaneous Cooling & Heating50-113°F (10-45°C)
Glycol Allowance20-40%
Glycol TypePropylene
Connection Ratio50(60)-130%

With addition of the newly developed VRV-WII geothermal control logic, the operation range can now be extended to as low as 24.8°F (-4°C) entering water temperature (EWT) in heating, This is achieved with the addition of a field installed replacement condenser control board.