To maintain the desired gas volume in a surge vessel it is necessary to periodically top-up the gas charge. This is normally supplied from an air cooled reciprocating air compressor.

Raw or waste water and sewage systems are normally equipped with conventional lubricated machines. Potable water systems require contaminate free air which is achieved either by using multiple inline filters to treat the discharge of lubricated machines or by use of intrinsically oil-free compressors.

Reciprocating compressors have electric motor V-belt drives and are of the single or multi stage type depending on design conditions.

Unloading arrangements to facilitate starting, cooler(s), safety valve(s), delivery non-return valve and anti vibration mounts are normally supplied.

Special arrangements can be made to meet particular client specifications.