Diagram 3 Way Valve In Chilled Water System

Both 3 way and 2 way valves can serve many purposes.

Diagram 3 way valve in chilled water system. Variable primary chilled water pumping system with some 3 way valves single chiller single variable speed pump 3 way valves for some chilled water coils to maintain minimum flow required for chiller. As the temperature from the terminal unit or coil is satisfied the flow rate is reduced in the coil and the flow is diverted to the bypass. This is a low d p application. Chilled water schematics in this video we look at how to read a chilled water schematic for central plant chilled water system covering chillers cooling to.

Chilled water schematic and condenser water schematic how to read and understand the engineering drawings with real world examples illustrations animations and video tutorial. In the heating mode the return line from the room terminal units typically fan coils or unit ventilators bypasses the chiller and goes to a header that feeds the boilers. As in two way valves if the three way valve selected is less than line size don t forget the fp factor. A schematic of a generic system is shown in figure 2.

Fcu ahu applications of 2 way and 3 way valves. A chilled water system is a cooling system in which chilled water is circulated throughout. System flow below chiller min flow 250 gpm variable primary flow at 25 system load two way valves control capacity by varying flow of water in coils per chiller system load 50 tons 176kw 50tons 176 kw primary bypass flow 250 gpm 95 l s 150 gpm 9 5 l s delta t 12 of 6 7 oc 100 gpm 44 ºf 6 3 l s 6 7 ºc 56 ºf 13 3 ºc 150. Resize the valve applying the fp factor to find the new cv.

The three way valve immediately above the chiller at the bottom of the diagram switches the system s mode of operation. The sketch below shows a three way diverting valve system. They are both employed in chilled water systems as previously mentioned. Chillers have minimum flows that are typically higher than their associated vfds and pumps.

The 3 way valves restrict water supply to the cooling coil allowing some chilled water 44 f to bypass directly into the return line water stream temperature of 56 f. The decision over whether to use a 2 way or 3 way valve is made at the design stage based on application specific design and cost considerations. Covering chillers pump sets ahus risers primary and secondary systems cooling towers and bypass lines. Three way control valves may be diverting or mixing depending on how they are ported and controlled.