30 – 45 kW screw compressors
Mid-size plant room machines with full remote monitoring.
Technical data
- Free air delivery
- 1.3 – 9.3 m³/min
- Working pressure
- 5 – 13 bar g
- Motor power
- 30 – 45 kW
- Weight
- 887 – 1,075 kg
- Noise level
- 66 – 70 dB(A)

Overview
At this size the compressor stops being a piece of equipment and starts being a utility. If it stops, the plant stops. That changes what matters: not peak flow on a datasheet, but how predictable the machine is over ten years.
Every GAC-S unit from 30 kW upward ships with the Green Air controller and a connectivity module. You get running hours, load percentage, discharge temperature and service countdown on your phone, and so does our service team, which is usually how a problem gets caught before it becomes a breakdown.
Key benefits
Monitored from day one
Free remote monitoring for the first three years. Alerts go to you and to the engineer who covers your area.
Serious heat recovery
Up to 76% of the electrical input can be recovered as hot water at 70 °C: real money back in plants that need process hot water.
Low starting current
Star-delta as standard, full soft start optional. Important on generator supply or a weak grid connection.
Quiet enough for the shop floor
68 – 72 dB(A) in a standard canopy. No separate compressor house required in most plants.
How it is built
At thirty kilowatts and above the compressor stops being equipment and starts being a utility. It is built accordingly. A heavier airend running at a lower speed, a larger oil charge, and a cooler with enough margin that the machine is not living at the top of its temperature range.
Heat recovery is designed in rather than bolted on. Up to seventy six per cent of the electrical input comes back as hot water at seventy degrees, which in any plant that needs process hot water is real money rather than a marketing line.
Vibration is low enough that a level concrete slab is all the foundation these machines need. We supply the drawings and the loadings with the order so the civil work is done once.
- Heavier airend at a lower running speed
- Cooler with margin for high ambient
- Heat recovery up to seventy six per cent
- Level slab foundation, no special base
- Star delta standard, soft start optional
- Sixty eight to seventy two dB(A) in the canopy
- Air cooled or water cooled
- Variable speed across the band
What the controller does
Full colour screen with the machine's state on the home page. Pressure, load percentage, running hours, discharge temperature and how long until the next service.
A real time clock starts and stops the compressor to your shift pattern instead of leaving it loaded through the night. A second pressure setting covers the hours when the plant does not need full pressure, and those two settings together are the cheapest saving on any compressed air system.
The connectivity module sends the same data to your phone and to our service team. That is usually how a problem is caught early, because somebody is looking at the trend even when nobody in the plant is.
- Colour screen with the machine state at a glance
- Real time clock for shift scheduling
- Second pressure setting for quiet hours
- Discharge temperature and load trends
- Remote monitoring free for three years
- Sequencing for multiple machines
- Fault history log
- Automatic restart after a power failure
Parts and service kits
A service kit holds every wear part for that interval in one box, so nothing is found missing halfway through and the machine goes back together the same day.
Kits are made up by interval. Air and oil filters with an oil sample at two thousand hours, the separator and oil change with a cooler clean at four thousand, and a full performance check with a motor regrease at eight thousand.
At this size the arithmetic on genuine parts is straightforward. A separator with a higher pressure drop costs more in electricity in one year than the saving on the part, and the machine gives no sign that it is happening.
- Two thousand hour consumable kit
- Four thousand hour separator and oil kit
- Eight thousand hour major service
- Motor regrease included at eight thousand
- Oil analysis with every consumable kit
- Genuine fluid to the tested specification
- Confirmed against your serial number
- Fixed price under a service plan
Model range
Fixed speed
- 7.5 bar g
- 5.75 m³/min
- 10 bar g
- 5.01 m³/min
- 13 bar g
- 4.27 m³/min
- Noise level
- 67 dB(A)
- Weight
- 887 kg
- Dimensions L x W x H
- 1722 × 920 × 1659 mm
- 7.5 bar g
- 7.00 m³/min
- 10 bar g
- 6.17 m³/min
- 13 bar g
- 5.30 m³/min
- Noise level
- 68 dB(A)
- Weight
- 912 kg
- Dimensions L x W x H
- 1722 × 920 × 1659 mm
- 7.5 bar g
- 9.30 m³/min
- 10 bar g
- 8.30 m³/min
- 13 bar g
- 7.40 m³/min
- Noise level
- 70 dB(A)
- Weight
- 1,075 kg
- Dimensions L x W x H
- 1448 × 968 × 1806 mm
Variable speed
- 5 – 10 bar g
- 1.33 – 5.53 m³/min
- Noise level
- 66 dB(A)
- Weight
- 925 kg
- Dimensions L x W x H
- 1722 × 920 × 1659 mm
- 5 – 13 bar g
- 1.44 – 6.90 m³/min
- Noise level
- 67 dB(A)
- Weight
- 952 kg
- Dimensions L x W x H
- 1722 × 920 × 1659 mm
- 6 – 10 bar g
- 2.50 – 9.25 m³/min
- 6 – 13 bar g
- 2.50 – 9.10 m³/min
- Noise level
- 69 dB(A)
- Weight
- 990 kg
- Dimensions L x W x H
- 1448 × 968 × 1806 mm
FAD measured to ISO 1217 Edition 4, Annex C and E at 1 bar a intake, 20°C, 0% humidity. Noise measured to ISO 2151 in free field conditions, tolerance ± 3 dB(A). Water-cooled versions of every model are available. Ask us for their sheet.
Frequently asked questions
At what size does a compressor become plant infrastructure?
Around here. Above 30 kW, if it stops the plant stops, so what matters is not peak flow on a datasheet but how predictable the machine is over ten years.
What does remote monitoring actually give me?
Running hours, load percentage, discharge temperature and service countdown on your phone, and on our engineer's. That is usually how a problem gets caught before it becomes a breakdown.
Is heat recovery worth it at 45 kW?
If you already buy hot water, yes. Up to 76% of the electrical input comes back as water at around 70 °C, which on two shifts is enough to pre-heat boiler feed water for a small plant.
How much heat will it put into my plant room?
Almost all of the input power. A 45 kW machine needs roughly 6,000 m³/h of ventilation air to stay within its rating. Under-ventilation is the main cause of summer trips.
Why does starting current matter at this size?
Because on a weak grid or a generator it decides your supply sizing. Star-delta is standard. Full soft start is an option and a variable speed machine effectively removes the problem.
How noisy is a 45 kW machine?
68–72 dB(A) in a standard canopy. That is quiet enough to sit on the shop floor in most plants without a separate compressor house.
Air-cooled or water-cooled at this size?
Air-cooled is normal up to 90 kW. Water cooling only becomes the sensible answer here if the plant room genuinely cannot shed the heat.
What is the airend life?
40,000 hours or more with correct oil and filtration. We assess it at that point and offer a rebuilt exchange unit rather than a repair that keeps the machine down.
Should I buy fixed speed or variable at 37 kW?
Log first. Two shifts with varying demand almost always favours variable speed. A continuously loaded process line usually does not.
What is included in commissioning?
Positioning, pipework connection, electrical checks, a performance test against the quoted flow and power, controller setup and operator handover, with the measured figures written down.
Related products

Direct driven screw compressors
Motor coupled straight to the airend. 55 to 250 kW, nothing to slip.
- Free air delivery
- 7.8 – 43.0 m³/min
- Working pressure
- 7 – 13 bar g
- Motor power
- 55 – 250 kW

Variable speed screw compressors
The motor follows the demand. 7.5 to 280 kW, 8 to 13 bar g.
- Free air delivery
- 0.3 – 50.0 m³/min
- Working pressure
- 8 – 13 bar g
- Motor power
- 8 – 280 kW

Two stage screw compressors
Compression in two steps. 45 to 500 hp, 4.5 to 12.5 bar g.
- Free air delivery
- 6.6 – 101.3 m³/min
- Working pressure
- 5 – 13 bar g
- Motor power
- 45 – 355 kW

Permanent magnet screw compressors
IE4 and IE5 class motors with variable speed built in. 20 to 500 hp.
- Free air delivery
- 0.3 – 109.0 m³/min
- Working pressure
- 7 – 30 bar g
- Motor power
- 8 – 55 kW
Not sure which model you need?
Send us your air demand, working pressure and running hours. Our engineers will size the machine and send a written recommendation, no cost, no obligation.