Medical/Dental Air Plant

The compressed air systems consists of 2, 3 or 4 separate compressors, with accordingly to calculated plant capacity pressure tanks, filter systems, compressed air compressors, dryer and pressure reducer stations. This enable maintenance and repairs possible without interruption of the air supply, offering additional operational security. Also, the system function is continuously monitored automatically, malfunctions are displayed immediately and can be transmitted to the hospital Building Management System (BMS).
As each installed system consists of many separate components, only proven components of the highest quality are selected which conform to all relevant regulations and standards. The compressed air supply systems built by Schönn, not only meets the requirements of the ISO 7396-1, HTM 02-01 and HTM 2022 standards, thanks to its particularly effective pressure conditioning unit with 5 filter phases and an adsorption dryer, the systems also comply with the standards set by the European Pharmacopeia. Each system has been tested and got CE certificated.


  • Proven design based on established technology
  • Flexible design allows compact installations in existing and new plant rooms.
  • Duplex heatless desiccant air dryer including economy circuit.
  • Electronic controls and monitoring ensure reliable plant operation.
  • Plant controls are configured to minimise running costs.
  • Controls include connections for medical gas alarm system and BMS.
  • Oil injected screw compressors for quiet and vibration free operation (Other type compressors are also available)
  • Use for patient’s breathing – Medical Air, surgical instrument, other medical equipment.
  • Medical Air Plant complies with: Medical Device Directive MDD 93/42/EEC, EN ISO 7396-1 and ISO 14971, Health Technical Memorandums HTM 02-01 and HTM 2022


All Medical Air Plants are equipped with a duplex set of carefully selected filters, to ensure maximum air quality, and extended service life of the desiccant.
1st Pre-filter – to remove airborne dirt particles, dust and water / oil droplets, from the compressed air.
Activated Carbon filter – to remove by adsorption, hydrocarbon vapours, and odours.
Bacterial Filter – to ensure that the delivered air is free of bacterial contamination.
All filters are provided with differential pressure gauges to indicate when a new element is require and due to the full duplex assembly, elements can be c.hanged without the need for a system shut down.
All filters provide, dirt, dust, oil, water vapor and bacteria free breathable air to Hospital Medical Air System.

Air Receiver

One or more air receivers will be supplied manufactured and tested to BS EN 286-1:1998. Other standards such as ASME, and third party designs / inspection are available upon request.
The receiver(s) is supplied with inspection access panels and automatic drain with manual by-pass.
Each receiver is also supplied with a pressure gauge, safety relief valve and fusible plug, and is complete with lifting lugs and mounting feet.


Atlas Copco Air compressors are used in Medical Air Plants to supply compressed air. The compressor which takes the purified air in, sends it to the Air Receiver at the required pressure. The compressors are generally oil type or oil free type;capacities vary from 2,1 1/s.(126 lpm) to 31.7 1/s(1902 lpm).Power consumptions are in a range of 1,5 KW to 15 KW,and there are types with or without silencers. 

Besides the types mentioned above,there are oil lubricated screw type comlpressors to be used in hospitals which require high capacity. Their capacities will be in a range of 8 l/sec (480 Ipm) to 222 l/sec (13320 Ipm) at 10 bar pressure with a power consumption of 7,5 kW to 75 Kw.

Air Dryer

  • Valve for minimization of regeneration air.
  • Continuous dew point measurement in the outgoing air on digital control panel
  • Control system with valve monitoring and emergency switching
  • Visual display and collecting malfunction alarm for dew point and system operation
  • Air quality according to the European Pharmacopoeia
  • Space-saving, packaged design
  • Simple modification of existing plants without additional control panels

Touch Screen Control Panel


  • Colourful and easy-to-use display.
  • The system has automatic and manual operation feature.
  • Adjustable working system up to 4 compressors.
  • Audio-visual status display and fault display.
  • Fault alarm statuses are designed according to HTM standards.
  • Synchron Aging work system.
  • Remote access with Modbus-RTU and connection to Hospital BMS.
  • Compressor temperature can be adjusted as PT100 and dry contact.
  • Pressure measurement units: mbar, kPa and Psi
  • The compressor information is displayed both on the touch screen and by the LED signals on panel: “cut in”, “cut out”, “defective”
  • The compressor transition times are preset at the factory, but these transition times can be adjusted according to the tank reserve, capacity required by the hospital etc. (While one compressor is running, reserve compressor starts if the running compressor does not meet the required capacity.)
  • Compressor start-stop value can be adjusted.
  • Display tank pressure and dryer pressure value.
  • Display dew point value.
  • Display power failure, thermic failure of the compressors.
  • The compressor can be deactivated when necessary.


  • System detects deactivated compressor(s) and reserve compressor(s) will be activated.
  • The operation and failure status of the compressors and dryers are animated on the touch screen.
  • Compressor, dryer and alarm status are displayed on the panel by LED signals according to HTM standards.
  • The PCB system can operate on its own when any fault condition occurs on the panel.
  • The transit times of the dryer can be set by the user.
  • The dryer transition times are preset at the factory, but these transition times can be adjusted by user.
  • Display dryer status: defective and humid.
  • The tube group operates alternately according to interval time.
  • Group cylinder transitions automatically switch to higher dew point values. (right group from left group, left group from right group)
  • When the cylinder is defective, the other cylinder automatically cut in.
  • The system can be operated on touch screen or computer hardware when requested.
  • If all the cylinders are defective, automatic flow is provided by the by-pass system.
  • By-pass system provides automatic flow even during power cuts.
  • Language selection (German-English)
  • Authorized person access by password.