Post-Purge Pressure Check
Use the PacWizz completion pressure, current tank pressure, and timers to estimate pressure loss and assess the tank before beverage transfer.
What happens after purging?
Once the purge is complete, PacWizz records the pressure at completion and the time the purge took. It continues showing current tank pressure and total elapsed time.
These readings help you judge whether the assembled tank is holding pressure before transferring beverage into it. This is a pressure-hold check, not a certified tank pressure test.
Read the four values
| Display value | Meaning |
|---|---|
| Finish pressure | Actual tank pressure recorded immediately after the purge finished |
| Purge time | How long the purge took |
| Current brite pressure | Tank pressure now |
| Total elapsed time | Time since the purge began, including the time after completion |
The actual recorded finish pressure may differ slightly from the value you selected in Purge SetUp. Use the recorded value when comparing readings.
Estimate pressure loss per hour
First calculate the time since completion, not the entire time since the run began:
Hold time = Total elapsed time − Purge time
Pressure loss = Recorded finish pressure − Current pressure
Pressure loss per hour = Pressure loss / Hold time in hours
If you work in minutes, multiply the loss per minute by 60 to get psi per hour.
Worked example from the manual
- Pressure drop: 0.57 psi.
- Time since the purge finished: 13 hours 42 minutes.
- Hold time in minutes:
(13 × 60) + 42 = 822. - Pressure loss per hour:
(0.57 / 822) × 60 ≈ 0.0416 psi/hour.
The manual rounds this to about 0.041 psi/hour. These values illustrate the calculation only; they are not an acceptance limit or a recommended hold duration.
Do not leave a tank actively purging overnight. The long elapsed-time example in the manual is not an instruction to run an unattended overnight purge. Follow your facility's supervision and pressure-hold procedures.
Interpret the result carefully
- A falling pressure may indicate a leak, but temperature changes also affect pressure.
- A very short observation interval or small pressure change may be difficult to distinguish from normal measurement variation.
- There is no universal pass/fail pressure-loss threshold in the supplied manual. Use your facility's requirements and ask BrewWizz for advice if the loss is unexpected.
- The oxygen estimate does not establish that the tank is leak-free.
If the tank loses pressure unexpectedly, check the assembly and connections under your facility's safe isolation/depressurization procedure before transfer. Record the pressures, timers, settings, and any temperature change when contacting support.
Next steps
- Troubleshooting — pressure and connection problems.
- Specifications — sensor limits and measurement characteristics.
- Running a Tank Purge — review the operating sequence.