EMERY Expansion Vessel

Install on iPad: open this hosted page in Safari → Share → Add to Home Screen → turn on Open as Web App → Add.

Quick vessel sizing

Uses the current EMERY quick method unchanged. Enter known system volume or estimate at 12 L/kW.

Total system water volume

Maximum flow / design temperature

Don't know the exact water volume?

Estimate from Total boiler output

Litres per kW

Estimate: 2,340 L

Height to highest point

Cold fill / pre-charge pressure

bar

Safety valve / PRV

bar

Existing vessel size

Existing / stated vessel charge

bar

Recommended next standard vessel

— L

Enter the system water volume.

System volume

— L

Expansion volume

— L

Acceptance factor

—

Final design pressure

— bar

Show workings & guidance

Enter system water volume to calculate.

Commercial system water content

Build actual system volume from boilers, components and measured pipework, or enter a known total.

Number of boilers Output each

Water content each

Known total system water volume (overrides component total)

Radiators / emitters / AHUs

Buffer / low-loss header

Other components

Pipework sections

Use actual internal bore, not nominal pipe size.

Internal Ø (mm)

Length (m)

System water volume used by engine

0.0 L

Pipework: 0.0 L • Total boiler duty: 195 kW

Commercial pressure & vessel check

Maximum temperature Height to highest point

Cold fill / design pre-charge

bar

Safety valve / PRV

bar

Existing vessel

Existing / stated charge

bar

Recommended next standard vessel

— L

Add system water content.

Show full engineer calculation

Add system water content to calculate.

Method & safety note

This release changes deployment and iPad compatibility, not the current sizing method. Quick and Commercial modes use the same EMERY-EV-QUICK-1.0 acceptance-factor engine: expansion volume = system volume × expansion factor; final design pressure = PRV − 0.3 bar; acceptance factor = 1 − (Pi+1)/(Pf+1); vessel = expansion volume ÷ acceptance factor; then +10% heating reserve and round up. Manufacturer/project requirements take precedence. Water systems only; glycol/antifreeze requires fluid-specific data.