Issue
The V321 globe valve is described as a "Mixing valve", but a diverting application is required.
Environment
Valves
Actuators
Diverting application.
V321
VTRE
Cause
The incorrect positioning of the V321 globe valve in the flow pipe work will lead to water hammer. Water hammer can lead to bad vibration and potential damage to the valve and pipe work.
Resolution
The V321 is a globe valve, and this style of valve must be fitted so that the water flows proportionally across the valve seats. This is achieved when the valve is fitted into the system return pipe work.
In the above drawing, it can be seen that the valve is fitted in the system return with its common port (AB) connected directly to the main system. Port A of the valve is connected to the heat load, and port B of the valve is connected to the bypass connection. This means that water will flow through ports A - AB if the valve is open, of ports B - AB if the valve is closed.
I must fit my valve in the system flow, what can I do?
If the valve must be located in the system flow, then this valve type is not suitable, and a different valve must be chosen.
The most logical choice of valve suitable for location in either the flow or return is the VTRE
It must be noted that this valve only has a rating of PN6 as opposed to the V321 which is rated PN16.
For the VTRE data sheet please click HERE.
Suitable actuators for the VTRE are either the M9B or EM9.
For the data sheet for the 24 volt / 230 volt M9B click HERE.
For the data sheet for the 0-10v DC EM9 click HERE.
