Check 6 — Leak Testing
Test the arm circuit for leaks using the gloved finger pressure-hold test and the separator decay test — Health Check Idents U and V.
Check 6 — Leak testing
Verify the arm circuit holds pressure with two leak tests — a sealed-port pressure hold and a separator-equipped decay test. These are the most sensitive tests in the Health Check, and the ones most likely to reveal a slow fault that has not yet caused an obvious symptom.
Preconditions
Step 6: Reconnect CO₂ to CO₂_In
Disconnect from ARM
Disconnect the push-to-connect from the ARM connection.
Reconnect to CO₂_In
Re-attach it to the CO₂_In port.
Allow to settle
Wait 2 minutes for pressure readings to stabilize before starting either test.
Do not rush the settling time. Starting either test before readings are stable is the most common cause of a false failure here.
Check 6.1 — Gloved finger test (Ident U)
Using a gloved hand, cover and plug the ARM connection to seal the arm circuit. Observe the Brite pressure reading for 30 seconds.
Plug the ARM connection with a gloved finger and watch the Brite pressure.
| Ident | Criterion | Pass |
|---|---|---|
| U | Brite pressure should not increase by more than 0.10 psi over 30 seconds | Increase < 0.10 psi |
What the gloved finger test looks for
With CO₂ on the CO₂_In port, the Head_Transfer solenoid should be closed and the sealed arm circuit should hold steady. A rising Brite pressure means gas is seeping past the Head_Transfer solenoid.
Documentation discrepancy
The Health Test Procedure specifies a pressure increase of no more than 0.10 psi, and the troubleshooting guide agrees. "Pressure increased on finger test" indicates a leaking Head_Transfer solenoid. However, the Results Form records this row as Start − Finish, which computes a pressure drop. Record Finish − Start for this row until the form is corrected, so a positive value indicates the pressure rise the test is looking for.
If U fails
Replace the Head_Transfer solenoid — it has a small leak past the seat.
Check 6.2 — Arm hose and separator test (Ident V)
Connect arm hose with separator
Attach the arm hose with the separator fitted to the ARM connection.
Close swiffer valve
Ensure the swiffer drain valve on the separator is closed.
Press Up for one pulse
Briefly press the Up button to pressurize the arm circuit with one pulse of CO₂.
Observe for 30 seconds
Watch the Brite pressure for 30 seconds. It should not drop by more than 1.5 psi.
The arm circuit under test, with typical before and after pulse readings.
| Ident | Criterion | Pass |
|---|---|---|
| V | Brite pressure should not drop by more than 1.5 psi over 30 seconds | Drop ≤ 1.5 psi |
Recording V results
Record the start pressure, finish pressure, and the difference, Start − Finish, on the Results Form. In the example readings, one pulse took the circuit from 0.001 to 13.277 psi — the absolute value is not important, the rate of decay is.
If V fails
- Check the swiffer valve. An unclosed or worn swiffer valve is the most common cause.
- Remove the separator and recheck. If the leak disappears, the separator is at fault.
- Suspect a leak in the arm hose or separator itself — check fittings and connections along the whole run.
- Check the vent solenoid. A vent solenoid stuck open will bleed the circuit — see Ident M in Troubleshooting by Symptom.
Next step
Check 7 — Stone/Isolation Valve
Verify the stone isolation valve in Carbonation mode — the final check.