Pillar guide
Gas Proving Systems & Pressure Proving Panels
A gas proving system tests the downstream pipework for soundness before releasing gas. If an appliance tap has been left open or a joint is leaking, the sequence fails and the solenoid valve stays shut.
- Proves pipework soundness at every start-up
- Detects appliance taps left open overnight
- Often combined with ventilation interlock in one panel
System architecture
The proving sequence
- Operator presses START; ventilation proof is confirmed
- The panel pressurises the test section via the proving valve
- A pressure switch monitors decay over a fixed test period
- Pass: the main solenoid valve is energised and gas is released
- Fail: the panel alarms with a proving fault and gas remains isolated
Installation and commissioning
- Correct test volume and switch set point for the pipework size
- Proving valve, main valve and vent line positioned per manufacturer data
- Recorded test period, set pressures and pass/fail thresholds
- Operator training on start-up and reset
Proving faults and what they mean
| Panel indication | Meaning | Action |
|---|---|---|
| Proving fail on start-up | Downstream leak or open appliance tap | Close all taps and repeat; if it fails again, tightness test |
| Proving times out | Test volume too large or proving valve restricted | Review commissioning settings |
| Passes then trips in service | Ventilation proof dropping, not a proving fault | Investigate fan/pressure switch |
Frequently asked questions
Do I need proving as well as an interlock?
Proving is required where a risk assessment or IGEM/UP/19 design identifies the possibility of gas being released into an unattended space — commonly in kitchens with multiple appliance taps and in plant rooms.
Why does proving fail every morning?
The most common cause is an appliance isolation tap left open at close-down; the second is a weeping joint or gas tap gland.
Related guides
Gas Interlock Systems
Installation, servicing, testing and fault-finding for kitchen ventilation interlocks.
Gas Solenoid Valves
Normally closed automatic shut-off valves and diagnostics.
Gas Safety Control Panels
Interlock and proving panels, indicators and diagnostic codes.
Sensors & Controls
Air pressure switches, airflow sensors, current monitors, e-stops.
Plant Room Gas Detection
Boiler house detection, automatic isolation and ventilation.
Commercial Kitchen Gas Safety
Ventilation interlock, airflow proving and CP42 compliance.
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