Condensation Control In Electrical Enclosures

Electrical enclosures are used to protect delicate electronic equipment from water and dust but also for safety. As the components inside the enclosure are live, they need protection to prevent electrical shocks.

Condensation In Enclosures Axair FansCondensation, caused by warm moist air coming into contact with cooler surfaces causes electrical equipment housed within enclosures to fail prematurely. Condensation will only form at, or close to Dew point (65% humidity), but oxidation / rusting can take place at medium levels of relative humidity at 60% depending on the type and levels of contaminants in the air /water mixture. Outdoor equipment is particularly prone to condensation given the change in temperature as daytime warmth turns to the cold of the night. Condensation may also form in indoor enclosures when humidity levels are too high and temperatures vary.

By keeping an enclosure at a temperature of as little as 5 degrees higher than that of the ambient temperature, condensation can be eliminated. The warmer the air, the more water vapour it can contain. When air is cooled it can no longer hold the water vapour and reaches its dew point – this is where condensation arises.

The most effective solution to prevent condensation included heaters, hygrostats and thermostats. Heaters are typically applied to enclosures to ensure they stay above the minimum operating temperature and to control condensation formation.

Enclosure Solutions:

For many years, Axair has operated in the thermal management market, supplying high quality enclosure solutions from Italian manufacturer, Fandis, including heaters, lights, thermostats and switches to protect and equip as required by our customers. Effective thermal management is essential for ensuring the reliability of electronic components within an enclosure. Our enclosure accessories will meet customer needs for climate control and prevent the premature failure of equipment.

anti_condensation_heaters Axair fans enclosures

Axair heaters have a self regulating PTC element and are made from a black anodised aluminium. Heaters should be used in circumstances where there is a change in temperature in the enclosure or cabinet that may result in condensation.


Axair Fans offer 2 variants of thermostats : normally-closed and normally-open.

–          Normally-closed thermostats are used with anti-condensation heaters to maintain a pre-set minimum temperature that will prevent condensation.

–          Normally-open Thermostats are used to switch the cabinet fan on at a pre-set maximum temperature, replacing the warm air with cooler ambient air. These can also activate an alarm to indicate high internal temperature.

Enclosures Thermostat Axair FansA change-over version is available, which combines Normally-open and normally-closed, controlling both heaters and fans.

Using a thermostat can offer many benefits. They will save energy, only switching the fan/heater on when required and therefore extending the life of the fan/heater as a result. Furthermore when used with a fan filter they will reduce the need to replace or clean the filter media and therefore save on maintenance costs.

To buy thermostats and heaters online, visit our e-commerce website:



More Enclosure Ventilation News >> Enclosure Ventilation & Cabinet Cooling >> 

Comments are closed.