This article covers all scheduled maintenance tasks, filter and membrane service procedures, and troubleshooting for the most common fault conditions. Always power down and unplug the system before opening the cabinet or servicing any component.
Maintenance Schedule
| Component / Task | Deployable (Hard Case) | Standalone / NM400 | Part Number |
|---|---|---|---|
| All 3 filter elements (inspect) | Every 500 hours or 6 months | Every 125 hours or 2 months | — |
| All 3 filter elements (replace) | Every 1,000 hours or 12 months | Every 250 hours or 4 months | FRP-001 |
| Membrane elements (replace) | Contact South-Tek Systems — service at South-Tek facility | 400-129 (×2) | |
| Air compressor (replace) | Contact South-Tek Systems — service at South-Tek facility | Contact South-Tek | |
Filter Replacement Procedure
The N2-GEN™ 4 contains three filter elements that must be replaced together as a set (part FRP-001). Replacing only some filters and not others is not recommended — replace all three at the same time.
Filter Locations
| Filter | Location | Identification |
|---|---|---|
| Pre-compressor (air intake) | Top of the air compressor | Twist-on cap; no bowl |
| General purpose (particulate) | Right side of cabinet, closer to the rear | Clear bowl; pink/white filter element |
| Coalescing | Right side of cabinet, closest to the front | Clear bowl; green filter element |
Replacement Steps
- Turn the power switch to Off and unplug the power cord from the outlet.
- Remove the six (6) 10×32 screws from the cabinet cover and set the cover aside.
- Relieve all internal pressure before proceeding.
- Pre-compressor filter: Twist the filter cap clockwise to remove. Pull out the old filter cartridge and insert the new one. Reinstall the cap.
-
General purpose and coalescing filters: Remove each filter bowl by pushing up on the bowl and twisting counterclockwise one-eighth of a turn — it will then pull straight down.
- A rubber O-ring may come out with the bowl. If it does, reseat it in the housing before reinstalling the bowl.
- Unscrew the filter cartridge from inside the housing and replace with the new element. Pink/white element goes in the rear (general purpose) filter; green element goes in the front (coalescing) filter. Do not swap them.
- Before reinstalling the bowls, confirm the auto-drain float is seated all the way to the bottom of each bowl. The float must be in place — the system will not function correctly without it.
- Reinstall both filter bowls by reversing the removal steps.
- Reinstall the cabinet cover and all six screws.
- Plug in the power cord and turn the system on.
- If the storage tank is already full and the system does not restart, relieve a small amount of pressure by pulling the safety relief ring located in the upper left corner inside the cabinet, until pressure drops and the system cuts back on.
- With the system running, listen and feel around all filter connections for leaks. Confirm the pressure gauge on the filter assembly reads 110–120 PSIG. If pressure is lower, a leak is present — power off, depressurize, and inspect all fittings before resuming.
Membrane Elements
The two hollow-fiber membrane elements (part 400-129) are located at the rear of the generator cabinet — two long grey tubes mounted vertically. Membranes have a service life that depends heavily on filter maintenance. Running the system with overdue filters is the primary cause of premature membrane failure.
Membrane replacement requires opening the cabinet, disconnecting all push-on fittings, cutting and replacing cable ties, and carefully reconnecting all tubing in the correct orientation. The membrane tuning valve is factory-set and must not be adjusted during this process or at any other time. If membrane replacement is needed, contact South-Tek Systems at (910) 415-1880 for guidance or to arrange service.
Troubleshooting
System Will Not Power On
| Probable Cause | Corrective Action |
|---|---|
| No power supply | Confirm the power cord is fully plugged into a live 110 VAC / 20 Amp outlet; verify the circuit breaker has not tripped |
| Blown 8-amp fuse | Replace the 8-amp inline fuse on the control panel; investigate the root cause if the fuse blows again (part 400-133) |
System Powers On But Compressor Does Not Run
| Probable Cause | Corrective Action |
|---|---|
| Storage tank already at cut-out pressure | System is in normal Standby mode — the Standby (amber) light should be illuminated. No action required; compressor will restart automatically when pressure drops. |
| BlastOff™ alarm active (if equipped) | Find and correct the leak; cycle power to reset. See BlastOff™ troubleshooting below. |
Compressor Runs But System Never Enters Standby
| Probable Cause | Corrective Action |
|---|---|
| External leak in gas lines or fittings | Perform the external leak check procedure from the Installation & Startup article; repair any leaks found |
| Internal leak | If no external leak is found, open the cabinet and carefully feel around all internal hoses and push-on fittings by hand; repair any disconnected or damaged connections |
| Pre-compressor filter severely clogged | Replace the pre-compressor filter element; check if filter pressure gauge reads 110–120 PSIG after replacement |
| Pressure switch malfunction | If no leaks are found and filter pressure is correct, the cut-out pressure switch may be faulty — contact South-Tek Systems |
Low or No Nitrogen Output Pressure
| Probable Cause | Corrective Action |
|---|---|
| Storage tank outlet valve closed | Open the storage tank outlet valve fully |
| Downstream leak | Check all downstream fittings and hose connections; repair leaks found |
| Compressor output pressure low (filter gauge below 110 PSIG) | Replace all three filter elements; if pressure remains low after filter change, check for internal leaks and contact South-Tek Systems |
Low Nitrogen Purity
| Probable Cause | Corrective Action |
|---|---|
| Filter elements overdue or saturated | Replace all three filter elements immediately using FRP-001; allow system to run through a full pressurization cycle before testing purity again |
| Ambient temperature too high | Confirm ambient temperature is within the rated range for your configuration (40–90°F Deployable / 35–90°F Standalone). Membrane performance degrades in high ambient temperatures. |
| Membrane elements degraded or damaged | If purity remains low after a confirmed fresh filter change with correct pressure and temperature, membranes may be at end of life — contact South-Tek Systems |
Filter Service Light Illuminated
The Filter Service light (red) illuminates when the Electronic Service Indicator detects that a filter element is saturated. Replace all three filter elements immediately using FRP-001. The light will reset the next time the system is powered on after the filter change.
BlastOff™ Alarm Repeating (if equipped)
| Probable Cause | Corrective Action |
|---|---|
| Leak not yet corrected | Perform a thorough external and internal leak check per the Installation & Startup article; do not use power cycling as a permanent fix |
| BlastOff™ sensor sensitivity | If no leak can be found after a thorough inspection, contact South-Tek Systems — the sensor may need calibration or replacement |
When to Contact South-Tek Systems
- Low nitrogen purity that does not recover after a confirmed fresh filter change
- Internal leaks that cannot be identified or repaired with factory parts
- Filter assembly pressure gauge consistently reading below 110 PSIG with fresh filters installed
- Fuse blows repeatedly after replacement
- System never enters Standby with no leaks found
- Any membrane replacement or compressor service
- Any condition that cannot be resolved using this article
Related Articles
- N2-GEN™ 4 Deployable / NM400 — Overview & Specifications
- N2-GEN™ 4 Deployable / NM400 — Installation & Startup
- N2-GEN™ 4 Deployable / NM400 — Operation & Controls
- N2-GEN™ 4 Deployable / NM400 — Safety Guidelines
Contact South-Tek Systems
Phone: (910) 415-1880
Email / Ticket: support@southteksystems911.zendesk.com