Why Commissioning Data Matters
The commissioning sheet is one of the most important documents in your handover pack. It proves that the system has been installed and set up correctly, and it provides a baseline for future servicing.
A poorly completed commissioning sheet undermines the credibility of the entire installation and can cause warranty issues if the manufacturer disputes whether the system was commissioned properly.
The Essential Measurements
Pressure Readings
- Suction pressure: Measured at the service port on the suction line
- Discharge pressure: Measured at the service port on the discharge line
Both should be compared against the manufacturer's commissioning data for the ambient conditions at the time of testing.
Temperature Readings
- Evaporating temperature: Derived from suction pressure using a PT chart
- Suction superheat: The difference between suction line temperature and evaporating temperature
- Subcooling: The difference between condensing temperature and liquid line temperature
Superheat and subcooling are the two values most commonly recorded incorrectly. Always use a properly calibrated digital thermometer and take readings at the correct locations.
Electrical Readings
- Supply voltage: Measured at the outdoor unit terminals
- Running current: Measured with a clamp meter on the supply cable
Compare running current against the manufacturer's rated value. Significant deviation may indicate a problem with the installation or the system itself.
Pre-Commissioning Checks
Before recording commissioning data, always complete these checks:
- Nitrogen pressure test: Pressurise the system with dry nitrogen and hold for the manufacturer's specified duration (usually 24 hours). Record the test pressure and duration.
- Vacuum: Evacuate the system to below 500 microns and hold. Record the duration and final vacuum level.
- Refrigerant charge: If additional refrigerant has been added (beyond the factory charge for the pipe length), record the quantity added.
Tips for Professional Documentation
- Record every value, even if you think it's minor
- Use the correct units (MPa, bar, K, degrees C, V, A)
- Note the ambient temperature and conditions at the time of testing
- Take clear photographs of the nameplates before and after installation
- Keep the manufacturer's commissioning sheet alongside your own records
Let Us Handle It
If you've measured your commissioning values on site, you can enter them directly into the AirCon Docs project form. We'll incorporate them into a professional commissioning certificate that matches the manufacturer's format and includes all the data your customer needs.
If you skip the commissioning section, we'll still prepare your pack with the values marked as pending for completion at the first service visit.