Atlas Copco MAS GA 18
Oil-filled screw compressor
Single-stage oil-filled screw compressor Atlas Copco MAS GA 18 with air cooling and Elektronikon Graphic controller (series MAS GA 15–26, marine version). Air passes through an air filter and intake valve, is compressed in the screw unit, oil is separated in an oil‑separator tank, air exits via the minimum‑pressure valve and cooler. Manual includes: operating principle and regulation, controller menu, installation and electrical connection, start/stop, maintenance schedule, oil, filter and separator replacement, cooler cleaning, safety valve check, fault diagnosis, technical data.
Click a part on the model to see its number and purpose.Open the 3D trainer
Maintenance procedures
Oil inspection and topping up
- Press Stop button (9) and wait 5 min for foam to settle in oil tank. p. 81
- If level not visible in sight glass (Gl) – press emergency stop (S3), close discharge valve and open manual condensate drains. p. 81
- Release pressure: turn fill-neck plug (FC) one turn anticlockwise and wait a few minutes. p. 81Do not unscrew the plug completely while system is pressurised
- Remove plug and top up oil until sight glass is full; reinstall and tighten plug. p. 81
- Unlock emergency stop, select STOP icon on display and press reset before start-up. p. 81
Oil and oil-filter change
- Warm up compressor, stop, close discharge valve and disconnect power. p. 89
- Release pressure via manual drains, after a few minutes turn plug FC one turn. p. 89
- Open plug FC and drain oil through valve at bottom of oil tank; also remove drain plug at screw-compressor outlet. p. 89Drain oil from all points – residual old oil reduces new oil service life
- Close valve, reinstall plugs, tighten upper oil-cooler connection; dispose of oil. p. 89
- Remove oil filter (OF), clean mounting seat, lubricate new filter gasket with oil and hand-tighten. p. 89
- Fill oil through neck to middle of sight glass (Gl), keep out contaminants; tighten plug. p. 89Oil volume 12.2 L
- Run under load for a few minutes, stop, let oil settle. p. 90
- Release pressure with plug FC (one turn), top up oil to full sight glass, tighten plug. p. 90
- Clear service warning in Service menu. p. 90Do not mix oils of different brands or types
Oil-separator element replacement
- Warm up compressor, stop, close discharge valve, disconnect power. p. 90
- Wait a few minutes and release pressure by turning plug FC one turn. p. 90
- After 5 min remove oil separator (OS), clean mounting seat on collector. p. 90
- Lubricate new separator gasket with oil, mount and hand-tighten. p. 90
- Reset service timer in Service menu. p. 90
Air-filter element replacement
- Stop compressor and disconnect power. p. 88Never remove filter element while compressor is running
- Remove side panel. p. 88
- Remove air-filter cover (AF) by turning counter-clockwise; extract element, clean cover if needed. p. 88
- Install new element and cover. p. 88
- Clear air-filter warning in Service menu. p. 89
Cooler cleaning (air cooling)
- Stop compressor, close discharge valve, disconnect power. p. 90
- Cover all units under the coolers. p. 90
- Remove dirt with a non-metallic fibre brush. p. 90
- Blow air opposite to normal flow direction. p. 90If required up to 6 bar
- For chemical cleaning – consult Atlas Copco. p. 90Do not wash compressor with high-pressure water
Decommissioning
- Stop compressor and close discharge valve. p. 83
- Open manual condensate drain. p. 83
- Disconnect power and isolate from network. p. 83
- Turn plug FC one turn to release pressure. p. 83
- Isolate and depressurize the air system section, disconnect the discharge pipe. p. 83
- Drain the oil, drain the condensate circuit and disconnect the drainage pipe. p. 83
Maintenance intervals
| Item | When | Action | Manual |
|---|---|---|---|
| Daily | Daily | Check oil level and display readings, drain condensate under load, purge condensate, check DD/PD filter indicators | p. 85 |
| Every 3 months | 3 months (more often in dusty environment) | Inspect and clean coolers; blow out and examine air‑filter element; cable‑tray filter; on Full‑Feature – dryer capacitor and mesh | p. 85 |
| Annually | 1 yr | Replace DD and PD filters; inspect receiver (minimum wall thickness) | p. 85 |
| Service plan 4000 h | 4000 h or 1 yr | Tighten electrical connections, replace oil‑separator element and air filter element, clean coolers, check pressures/temperatures, test LED/display, check for leaks, suction hose, perform temperature protection test | p. 86 |
| Service plan 8000 h | 8000 h or 2 yr | Replace oil and oil filter, oil return line check valve, minimum‑pressure valve and thermostatic valve; wear kit and unloading valve kit; check safety valve | p. 86 |
| Gaskets and seals | At each maintenance | Replace all removed gaskets, O‑rings and washers | p. 85 |
Faults and what to do
Compressor starts but does not loadFaulty solenoid valve / stuck intake valve / leak in control lines / non‑sealing minimum‑pressure valveCompressor does not unload, safety valve tripsFaulty solenoid valve or intake valve does not closeCondensate does not drain under loadDrain line cloggedPerformance or pressure below normalFlow exceeds capacity, air filter clogged, solenoid valve faulty, leaks, intake valve not fully open, safety valve chokedElevated oil consumption, oil carried into the lineIncorrect oil (foaming), over‑filling, oil separator faulty, oil return line defectiveSafety valve trips after loadFaulty intake valve, minimum‑pressure valve or safety valve itself; oil separator cloggedHigh temperature at block outlet or air outletLow oil, insufficient cooling air, oil or air cooler clogged, bypass (thermostatic) valve faultyCompressor does not start, engine overload displayed on screenIncorrect phase sequence
Technical specifications
| Nominal operating pressure | 6.9 bar (max.) | p. 97 |
|---|---|---|
| Maximum unload pressure (Pack) | 7.4 bar (max.) | p. 97 |
| Minimum operating pressure | 6 bar | p. 97 |
| Engine power | 18.5 kW | p. 97 |
| Engine shaft speed | 3560 rpm (60 Hz) | p. 97 |
| Oil volume | 12.2 L | p. 97 |
| Thermostatic valve setting | 60 °C | p. 97 |
| Ambient temperature, min./max. | 0 / 46 °C | p. 97 |
| Screw unit outlet temperature (normal) | 55–65 °C above cooling air temperature | p. 94 |
| Thermal relay F21 setting, MAS 18 440/460 V 60 Hz | 23.1 / 22.1 A | p. 96 |
| Noise level | 67 dB(A) | p. 97 |
| Oil (replacement interval, Roto Synthetic Fluid Xtend Duty) | 8000 h / 2 yr (up to 40 °C); 6000 h above 40 °C | p. 86 |
Spare parts and catalogue numbers
| Part | Number | Qty | Manual |
|---|---|---|---|
| Air filter (AF) | 1 | p. 88 | |
| Oil filter (OF) | 1 | p. 89 | |
| Oil separator element (OS) | 1 | p. 90 | |
| Filling neck plug (FC) | 1 | p. 81 | |
| Minimum pressure valve (Vp) | 1 | p. 14 | |
| Inlet valve (IV) | 1 | p. 14 | |
| Load solenoid valve (Y1) | 1 | p. 14 | |
| Unload/dump valve (UV) | 1 | p. 14 | |
| Safety valve (SV) | 1 | p. 91 | |
| Engine temperature relay (F21) | 1 | p. 96 |
Source: manufacturer's manual “MAS18P-100 APB 440-460V 60 FM - ITJ396636 - Instruction Book”, 104 pages. Page numbers refer to the original. Check against the manual on board before work.
This page was translated automatically from the manual summary. Part numbers, codes and page numbers are as in the original.