Condensate drains are a commonly overlooked and forgotten component in a compressed air system, nevertheless they play a critical role in ensuring an efficient and reliable system. No matter how much investment is made in efficiency boosting features like Variable Speed Drive (VSD), correctly sized air receivers or lowering system pressure for example, neglecting to install and manage condensate drains correctly will offset some or all of your efficiency gains and cause ongoing headaches due to poor system reliability and increased operating costs.

Contaminants such as oil, metal, particles, rust and pipe scale are separated out of the system when separators and filters are working correctly. Condensate drains play a major role in the function of separators and filters and if they do not operate effectively these contaminants can carry downstream in the system and cause piping, instrument and tool damage as well as product spoilage.

Condensate drains improve efficiency by ensuring moisture and contaminants are drained from the system enabling filters and separators to operate at maximum efficiency avoiding carry over and system complications. Condensate that is not drained will carry through the system causing premature wear and tear which will reduce the lifespan of components leading to higher maintenance costs. Condensate can cause catastrophic damage to certain types of dryers and other equipment.

Condensate drains can be found on the intercooler, aftercooler, filter, dryer, receiver or at the point-of-use. There are numerous types and variants of condensate drains, but in most cases each type can be classified in one of two groups:

1)    Manually Controlled

2)    Automatic, No-Loss (Zero Air Loss)

1)   Manually Controlled

Valves are opened manually in these types of drains to remove condensation. As a manual drain it requires human resources to open the valve and drain the condensate at required intervals.

Commonly manual drains are left partially open which is effective at ensuring condensate is continuously removed but the negative is that it will also constantly leak compressed air as well. The resultant air leak leads to a significant drop in efficiency and will be reflected in excess energy usage required to cover the leak.

Alternatively if manual drains are not released at appropriate intervals then moisture and contaminants will carry over and cause damage and complications.

Manual drains are generally not recommended as determining required intervals to open the drain are complicated due to use and environmental factors which are constantly changing and requires a high level of planning to ensure it is managed correctly.

2)   Automatic, No-Loss Drains

Automatic drains continuously measure the amount of condensate present and open to release the condensate at set levels and durations. Automatic, Zero-loss drains also do not expel any compressed air, therefore do not cause any reduction in efficiency which maintains the integrity of the system. As condensate is removed thoroughly when required and without air loss, air quality is maximised as peak efficiency is maintained. The only disadvantage to some automatic drains is in lubricated systems, if not sized properly they can be susceptible to water/oil mixtures that can sludge and jam internal floats causing them to cease to open.

There are numerous types of automatic condensate drains that suit specific applications and operating conditions, these include:

  • Float Type
  • Electronic/Sensor Controlled
  • Timer Controlled
  • Motorised ball drain valve

The drain suited to a particular piece of equipment will depend on a number of variables such as system pressure, hours of operation, human resources to inspect and monitor equipment, temperatures and humidity to name just a few.

It is recommended a compressed air specialist is consulted when selecting condensate drains for your compressed air system as they can assist you in selection of the most appropriate condensate drain for your application. This will ensure efficiency and reliability are maintained and operating costs are minimised long-term.

If you would like assistance or advice on your current condensate drains or selecting the best condensate drains for your application don’t hesitate to contact Southern Cross Compressors on 1300 098 901 or simply complete the ‘Enquire Now’ form on this page.