First Start-Up & Commissioning Checklist – South-Tek Systems

Applies to: STS Series (5–100HP) · STSH Series · STSD · STSP · STSP2
The first operation of any South-Tek compressor must be performed by an authorized South-Tek service provider.

Pre-Startup Environment Check

Before energizing the unit, verify the installation environment meets the following conditions:

Ambient temperature: +33.8°F to +104°F (+1°C to +40°C)
Altitude: Not more than 3,280 ft above sea level
Humidity: Not to exceed 80%
Air quality: Clean, low-humidity, dust-free, with adequate ventilation
Hot air discharge: Hot exhaust air must be ducted away from the intake. Duct air resistance must not exceed 50 Pa (5 mm H₂O)
Floor: Level, vibration-free, sufficient load capacity for the compressor weight
Clearance: Sufficient space around all sides for maintenance access

▲ Attention If ambient temperature is at or below 32°F (0°C), the compressor control system will enter self-protection mode and prevent startup. The compressor room must be heated in cold weather conditions.

Compressed Air Line Connection

Connect piping from the compressor outlet to the dryer, air tank, and distribution network per the installation diagram.
Use a flexible hose or compensator at the compressor air outlet to absorb vibration and stress. Rigid connections that transfer stress to the air/oil cooler will cause cooler damage.
All pipe connections downstream of the compressor outlet must be tension-free and unstrained.
All hoses, fittings, and piping must be rated for the compressor's maximum operating pressure.

Note — STS Tank-Mounted Models: For STS-T series (tank-mounted), verify the integrated tank connections, drain valve, and safety valve are correctly installed and functional before proceeding.

Electrical Connection

⚠ Warning All electrical work must be performed by a qualified, licensed electrician. Verify available plant voltage matches the compressor nameplate before connecting power.

Check mains voltage at all three phases with a voltmeter. There must be no voltage fluctuation between phases.
Select cable cross-section accounting for voltage drop losses over the cable run length.
Install an appropriately rated circuit breaker in close proximity to the compressor.
Protect the mains panel against short circuit.
Verify all terminal connections are tight throughout the wiring and the compressor electrical panel.
Confirm proper grounding. The ground connection must comply with applicable standards.
Check motor thermal settings.
The compressor electrical panel requires L1, L2, L3/N and PE mains connections.

Note — Electrical Panel Certification: South-Tek screw compressor electrical panels are UL certified (file NITW.E532921 & NITW7.E532921) and built to UL 508A and CSA C22.2 No. 14 standards. The AirMASTER FORM controller display is also UL certified.

Oil Level Check

⚠ Warning Oil may be lost during shipping, installation, or handling. If the compressor runs out of oil, the screw assembly rotors can seize within seconds. Always verify oil level before the first start.

Check the oil level sight glass on the separator tank. Read the level with the compressor stopped, the system fully depressurized, and the oil allowed to drain back (at least 20–25 minutes). At this static condition the oil should sit between the middle and near the upper (MAX) limit of the sight glass.
If the level is low, add the correct oil type (S-Tek 46 or S-Tek 46 FG; see the label on the compressor) until the static level sits in the middle-to-MAX band of the sight glass. Initial filling and pre-start checks use this static level.
Never mix different brands or types of oil.

ℹ Note Read the oil level only with the compressor stopped. While the compressor runs, air-oil separation in the tank causes foaming and swirling, so the level seen during operation is not reliable and must not be used as a reference.

Water Line Connection (Heat Exchanger / Water-Cooled Models Only)

▲ Attention Before first start on any water-cooled or heat recovery model, establish and activate the water line circuit first. Operating with only the oil circuit active will damage the heat exchanger.

First Start Sequence

Remove the suction hose at the suction control valve. Open the suction flap and add 1–5 liters of the correct compressor oil into the airend inlet depending on airend size. Rotate the airend 1–2 turns by hand in the direction of rotation so oil fills the rotor pockets. Reinstall the suction hose and clamp securely.
Open the air outlet valve.
Energize the compressor. Run it briefly, then stop immediately. Verify the fan and main motor are rotating in the correct direction (match the rotation arrow on the airend/motor). If the controller displays a Phase Sequence Fault, the unit will not start — swap any two supply phase connections and recheck.
Check all AirMASTER FORM controller parameters for correct configuration.
Restart the compressor and allow it to run. Monitor for any abnormal vibration, noise, or leaks.
After running under load for several minutes, stop the compressor, allow the oil to drain back (at least 20–25 minutes), then recheck the static oil level and top up if needed.
Check all air line, water line (if applicable), and oil line connections for leaks.

ℹ Note On units rated 188 PSI and above, the recommended control air operating pressure is 6 bar (87 psi); the pressure regulator at the suction control valve is pre-set to this value. Do not adjust it. Verify this setting while running.

ℹ Note — Powering Down Before powering down or disconnecting the main breaker, let the compressor unload and the cooling fan stop (about 180 seconds). Powering down before the unit has vented and the fan has stopped can leave the airend pressurized and hot.

Commissioning Data to Record

During the commissioning run, record the following for the project file:

Supply voltage at full load and at no load, across all three phases
Motor amperage at full load and no load (T1/T2/T3), and voltage drop across the starter (L1/L2/L3)
Total package amperage at full load
Ambient temperature, and full-load air discharge, oil discharge, and oil injection temperatures (°F)
Measured flow (CFM) versus the dataplate rating (within ±5%)
Pressure setpoints (start/stop)
Total, loaded, and unloaded hours (controller P02)

Post-Commissioning Verification

Motor rotation direction confirmed correct
Fan rotation direction confirmed correct
No phase sequence fault on controller
Oil level within the middle-to-MAX band of the sight glass (checked static)
No air, oil, or water leaks detected
No abnormal vibration or noise
Control air pressure confirmed at 6 bar at suction control valve (units rated 188 PSI and above)
AirMASTER FORM controller parameters verified
Compressor loads and unloads at correct set pressures
Automatic stop (idle timer) functioning correctly
For water-cooled units: water flow confirmed, exchanger and lines leak-free
Mounting and piping bolt connections tight
All cabinet doors closed and latched

Need help? South-Tek Systems Service — Phone: (910) 415-1880 · Open a support ticket at support@southteksystems911.zendesk.com or through the Help Center.