Experts in fire protection


As a rule, the sprinkler pipe network is usually backfed through a compressed air water tank which is filled halfway with water. A compressed air cushion is situated above it. The container is exposed to regular oxygen entry, which is why the interior walls are protected with a coating against corrosion.

If the coating is faulty or damaged, corrosion can set in at this point and reduce the wall thickness. When this happens, the water line represents a particularly sensitive area from inside and the safety of the whole tank may be compromised. Moist ambient conditions can also corrode the containers from outside. In addition, flaking of the coating can clog the sprinklers in case of fire.


Compressed air reservoirs are subject to safety regulations. These require an inspection every five years by an approved inspection body. We will be happy to take on coordination with the inspectors for you. 

So that the test can be done correctly, the tank must be completely drained. This is then checked from the inside and completely cleaned. Should deficiencies be identified, these can be removed by the competent Minimax Service staff. 

By performing the legally required checks you are meeting your duty of care and duty as an operator and also increasing the operational reliability of your sprinkler system. In addition you are securing your investment and avoiding additional costs, because damage can be detected and corrected early on.

Scope of service

Audit accompanied by an accredited body

  • Appointment coordination with the inspectors
  • Draining and cleaning the inside of the pressure tank
  • Provision of a temporary compressor for filling the tank quickly
  • Renewal of the manhole cover seal
  • Filling and commissioning of the compressed pressure tank after the inspection has been carried out

Scope of service

After any detection of defects by the inspector

  • Shut-down and draining of the pressure tank
  • Replacement of defective components
  • Renewal of the inner coating of the tank as necessary
  • Any necessary welding in the tank
  • New acceptance as necessary by a recognized body (e.g. TÜV or DEKRA)
  • Filling and recommissioning of the pressure tank