Air dryer — Mattei MD20

Refrigerated air dryer that removes moisture from the compressed air system. It cools the air so water condenses and drains away, then reheats it before it leaves.

Mattei MD20 in the compressor room

Mattei MD20 in the compressor room




Location

Compressor room, beside the storage room

Access

Maintainers only

Serial number

220010311

Installed

May 2022

Operation

  • The dryer runs whenever the air supply is in use. Keep the air inlet and hot-air outlet clear.

  • After a full shutdown, start the dryer first, wait a few minutes, check the dew-point indicator and drainage, then start the compressor.

  • Leave it off for at least 5 minutes before restarting it.

  • Report a high dew-point reading, water downstream, leaks, abnormal noise or a drain that isn't working.

  • A flashing srv is a service reminder. Do the service rather than just clearing the reminder. One was reported on 31 May 2026; it has not been recorded as done.

Maintenance

Follow §6.1 of the manual: daily dew-point, drain and condenser checks; cleaning every 200 hours or monthly; annual service. Isolate power and air first and let hot parts cool. Clean the condenser with air at max. 2 bar, without bending the fins. Refrigerant and electrical work need qualified personnel.

Specifications

From the MD range catalogue:



Air throughput

2 m³/min at 7 bar, 25 °C ambient, 35 °C inlet

Pressure dew point

+3 °C

Power

0.31 kW, 3.1 A, 230–240 V single phase

Refrigerant

R134a

Connections

G 1″ BSP female

Size, weight

420 × 350 × 740 mm, 40 kg

Max. ambient / inlet temp

45 °C / 55 °C

Max. inlet pressure

14 bar

The older 2008 manual lists a different MD20 revision (430 W, 36 kg). Check the nameplate before relying on electrical or refrigerant data.

Documents

History

  • May 2022: installed, with the FM-0018C2 filter, replacing the failed Ceccato DLX22.

  • Autumn 2024: moved with the rest of the system to the current compressor room.

Not yet documented

  • Photo of the nameplate and controller

  • Which manual revision applies

  • Whether the srv service from May 2026 has been done