27 May
Uncategorized

VARIABLE SPEED CHILLER – PICV CONTROL

Variable Speed Chiller – Plant Room

with PICV control

Function

The variable speed chillers are connected to the controller, which controls the flow through each chiller by the PICV.

The controller measures the inlet and outlet temperatures to maximize Delta T and regulate the variable speed pump to maintain the required pump pressure.

For optimal chiller efficiency, the use of multiple chillers at lower capacity or cascade control at part load shall be selected, depending on the chiller design and control philosophy.

Benefits

  •         The PICV ensures balancing of the flow and eliminates the use of both static balancing valves and differential pressure control valves.
  •         Simple installation as only the PICV is required with no need for additional pressure or flow balancing valves.
  •         Low total pressure loss in the system due to simple design.
  •         The flow can be set directly on the PICV without the need of a manometer or a commissioning unit.
  •         The differential pressure only needs to be checked at the PICV to set the required flow.

Considerations

  •         A metering station can be placed on main line if additional flow verification is required by the witnessing authority.
  •         A minimum bypass flow can be required by the chiller to secure instant cooling or circulation of chemicals in the system. This should be placed at the most appropriate place in the system.
27 May
Uncategorized

BOILER – PICV CONTROL

Condensing Boiler – Plant room

with PICV control

Function

The fully modulating boilers are connected to the controller which controls the flow through each boiler by the PICV.

The controller measures the inlet and outlet temperature to maximize Delta T and regulates the variable speed pump to maintain the required pump pressure.

For optimal boiler efficiency, the use of either cascade or unison control is recommended.

Benefits

  •         The PICV ensures balancing of the flow and eliminates the use of both static balancing valves and differential pressure control valves.
  •         Simple installation as only the PICV is required with no need for additional pressure or flow balancing valves.
  •         Low total pressure loss in the system due to simple design.
  •         The flow can be set directly on the PICV without the need of a manometer or a commissioning unit.
  •         The differential pressure only needs to be checked at the PICV to set the required flow.

Considerations

  •         A metering station can be placed on the main line if additional flow verification is required by the witnessing authority.
27 May
Applications

STAND-ALONE TERMINAL UNIT – PICV CONTROL

Stand-alone Terminal Unit

with PICV control

Function

The room temperature in different applications, such as Fan Coil Units, Chilled Beams, Chilled Ceilings, Trench Heaters, is controlled by a room controller.

The room controller has a built in temperature sensor and delivers an output signal to the PICV actuator.

The control signal can either be modulating or on/off depending on the system layout.

Benefits

  •         The PICV ensures balancing of the flow and eliminates the use of both static balancing valves and differential pressure control valves.
  •         Simple installation as only the PICV is required with no need for additional pressure or flow balancing valves.
  •         Low total pressure loss in the system due to simple design.
  •         The flow can be set directly on the PICV without the need of a manometer or a commissioning unit.
  •         The differential pressure only needs to be checked at the PICV placed at the index point, or at the end of every branch.

Considerations

  •         Minimum differential pressure required for the PICV must be available at design flow.
  •         A metering station can be placed on the branch if additional flow verification is required by the witnessing authority.
27 May
Applications, Applications, Applications

STAND-ALONE TERMINAL UNIT – PICV CONTROL AND SELF ACTING THERMOSTAT

Stand-alone Terminal Unit

with PICV control and Self Acting Thermostat

Function

The room temperature in different applications, such as Fan Coil Units, Radiators and Trench Heaters, is controlled by a self-acting room thermostat.

The room thermostat has a remote sensor and can be directly connected to the PICV.

Benefits

  •         The PICV ensures balancing of the flow and eliminates the use of both static balancing valves and differential pressure control valves.
  •         Simple installation as only the PICV is required with no need for additional pressure or flow balancing valves.
  •         Low total pressure loss in the system due to simple design.
  •         The flow can be set directly on the PICV without the need of a manometer or a commissioning unit.
  •         The differential pressure only needs to be checked at the PICV placed at the index point, or at the end of every branch.

Considerations

  •         Minimum differential pressure required for the PICV must be available at design flow.

A metering station can be placed on the branch if additional flow verification is required by the witnessing authority