Four-way valve symbol
A four-way valve has four ports and switches flow between two pairs of them. It is used to reverse flow or swap between two units.
What the four-way valve symbol means
A four-way valve has four ports and switches flow between two pairs of them. It is used to reverse flow or swap between two units.
How it is drawn
Four triangles meeting at their points in the middle, one on each port.
The four-way valve symbol in each standard
Drawn as on most US-style legend sheets.
ISO 10628-2 has no separate symbol for this. Check the project legend sheet.
German (DIN): Vierwegeventil. See DIN P&ID symbols.
Where you see it on a P&ID
On flow reversal duties, switching filter beds and some hydraulic systems.
Tag codes
The four-way valve is commonly tagged:
- HV
Tag formats follow the project numbering procedure. For instruments, the letters follow ISA 5.1, explained on the instrument symbols page.
Related symbols
Frequently asked questions
What does the four-way valve symbol look like on a P&ID?
Four triangles meeting at their points in the middle, one on each port.
What is a four-way valve used for?
A four-way valve has four ports and switches flow between two pairs of them. It is used to reverse flow or swap between two units. You will find it on flow reversal duties, switching filter beds and some hydraulic systems.
What tag does a four-way valve have?
It is commonly tagged HV. The exact tag format comes from the project numbering procedure and the legend sheets.
Is the four-way valve symbol the same in ISA and ISO?
ISO 10628-2 has no separate symbol for this. Check the project legend sheet. Companies vary the details, so always check the legend sheets at the front of the P&ID set.
What is the four-way valve called in German?
Vierwegeventil. On a German R&I-Fließschema it is drawn to DIN EN ISO 10628-2.
- In production since 2014
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