A principle-level commissioning sequence that proves the safety devices and discharge before handover.
Commissioning an unvented cylinder is where the safety design is proven in practice. A principle-level sequence is:
- Confirm the installation matches the design and the unit is suitable for the supply.
- Fill the system, vent trapped air, and check there are no leaks before any heat is applied.
- Confirm the cold-water controls and the expansion provision are correct, including the vessel charge or built-in air gap as applicable.
- Energise the heat source and confirm the control thermostat holds the set temperature in normal operation.
- Confirm the independent over-temperature protection is present and functions as intended.
- Check the temperature relief valve and the discharge pipework, including that the discharge route is continuous, correctly sized and terminates safely where any discharge can be seen but cannot scald anyone.
- Complete the commissioning record, hand over to the user and explain the system and any discharge they might see.
The work and any servicing of unvented systems sits within a regulated competence, so commission to the current standards and the manufacturer instructions and only work within your qualifications.
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