Condair is the leading manufacturer and provider of complete solutions in the areas of humidification and evaporate cooling, with a comprehensive portfolio including products, services, experience and know-how. This enables them to create the ideal indoor climate while keeping energy consumption low and reducing impact on the environment. This holistic approach becomes more important with every day.
Whether you have experience in humidification or if this is your first time, AAQ will help you every step of the way, from exploring the potential for improved productivity, reduced waste or energy consumption, through a correct sequence of processes – from exploration, design, product selection, selection, installation, commissioning, training & familiarization and maintenance.
Together with Condair, AAQ provides a service you can trust.
The right humidity makes a decisive contribution in a variety of situations encountered in day-to-day life in the business environment as well as in private premises. The importance of humidity is so significant that clear directives exist in many countries for the operation and maintenance of humidification systems. It is scientifically proven that a real sense of well-being can only be achieved in a narrowly defined humidity range between 40 – 60 %. These values are often difficult to maintain under day-to-day conditions. This is why they provide a comprehensive range of different humidification systems embodying a variety of technologies to ensure optimal air humidification in every situation.
Two different processes exist and can be applied to increase the percentage of moisture of the air:
In isothermal humidification, water is carried until boiling to be dispersed in the air. This process requires a source of energy, however as the mass of the steam is lower than that of the air, the temperature of the air remains stable.
Fogging systems use compressed air to atomize water and create a stream of microscopic water particles which appear as fog. The water particles quickly change from liquid to gas as they absorb heat from the surrounding air. It is constant enthalpy process and air decreases its temperature. This evaporative cooling can provide energy benefits for systems with high internal heat loads.
Electrode and resistive are the two main types of electric steam humidifier a HVAC contractor will buy and install. Both are versatile and come in a variety of sizes for either in-room or in-duct applications.
From a contractor's perspective the main considerations when selecting a unit are often purchase cost and ease of installation. For a customer or end-user the initial cost is also important but so are on-going operating costs and maintenance requirements.
The main differences between electrode and resistive technologies are how they heat the water to create steam and how they control steam output.
The electrode boils water by passing electrical current through it. The more current passes through the water, the greater the steam production. So output increases with a higher water level or when higher mineral levels make the water more conductive.
To maintain an accurate output, the concentration of minerals in the water is regulated through drainage and replacement with fresh water. This typically allows for humidity control of around +/-5%RH.
Resistive humidifiers create steam through the transfer of heat from the resistance heater elements to the water. Steam output is controlled by applying more or less heat to the water rather than controlling water level or conductivity. This results in more accurate humidity control of around +/-2%RH with mains water.
As the mineral content of the water has no impact on steam output, resistive humidifiers can also operate on RO water. As the mineral content of the water is very low, this virtually eliminates scale build-up, significantly reducing maintenance requirements.
It also improves humidity control by removing the need for fresh (cold) water to be regularly introduced to reduce mineral levels. A consistent water temperature results in a consistent steam output and enables a resistive humidifier operating on RO water to control humidity to +/-1%RH.
Electrode humidifiers tend to have the lowest capital cost of the two technologies. Installation costs for both electrode and resistive are comparable plus both are simple to install as they require connection to power, water mains supply and drain only.
The cost of operating a steam humidifier is largely determined by two things. The energy required to turn water from a liquid to a gas and the cost of dealing with what's left behind in the humidifier after this has happened.
When run on mains water, the energy costs are the same for both humidifiers, as they use the same amount of electricity to create the steam. However, if the resistive unit is run on RO water, electrical consumption is less as very little hot water is sent to drain. Although energy consumption is improved by the use of RO water, water consumption is increased as 50% of the water is sent to drain as part of the initial filtration process.
With an electrode boiler, as steam is produced, any minerals in the water build-up within the plastic cylinder as limescale. When these cylinders are full of limescale they are replaced, which is straightforward and offers the benefit of very rapid maintenance and minimal downtime for the humidification system. The disadvantage is that cylinders can be expensive and represent an on-going spares cost.
As resistive steam humidifiers do not pass current through the water they can operate with stainless steel boiling chambers that can be cleaned rather than replaced. This avoids the expense of disposable cylinders reducing spares costs. So much so, that the initial cost of the more expensive resistive unit can be recouped within 18 months.
So although on-going operating costs can be less with a resistive humidifier, servicing takes longer as the unit needs to be emptied of scale. However, some advanced systems, such as the Condair RS resistive steam humidifier, reduce this service burden through innovative scale management features. An external scale collector allows limescale to be removed quickly and easily without needing to open the main body of the humidifier, greatly reducing service time.
As we've seen, both technologies have advantages and disadvantages and the choice of system largely depends on the end-user's needs. If very close humidity control is needed resistive humidifiers with or without RO water could be the best option.
If close humidity control isn't important, but simple maintenance with minimal downtime is, an electrode boiler with its replaceable cylinders could suit. But if a customer wants the lowest whole life cost across capital, service and consumables, then a resistive humidifier will provide this.
This electric steam humidifier delivers accurate humidity control without the expense of plastic disposable boiling cylinders and simplifies maintenance with its patented scale management system.
Scale that forms on the heating elements breaks off under normal operation and falls into the externally located scale collector tank. Scale removal is a simple process of draining the scale collector tank with the push of a button, allowing the unit to cool then disconnecting the tank and emptying it.
The Condair RS can operate with mains water to provide ±3%RH control or on reverse osmosis (RO) water to offer ±1%RH control. When operating on RO water, scale build-up is virtually eliminated, significantly reducing the unit's required maintenance.
By locating the water inlet and drain between the twin walls of the outer cylinder wall and an inner cylinder liner, the temperature is kept at a level that inhibits scale formation in this area. This "cold water pool" prevents blockages of the inlet and drain by scale to further enable extended periods between servicing.
An advanced touch screen controller provides intuitive control over operation and very detailed reporting, including downloading performance, fault and service history into Excel for advanced diagnostics. BMS connectivity is standard with BACnet and Modbus protocols.
The Condair EL electrode boiler steam humidifier provides reliable steam humidification and is easy to install, use and service. It can be used with steam lances to humidify an air handling unit or duct, or with a fan unit to directly humidify a room.
The steam cylinders of the Condair EL last up to three times longer than similar models due to advanced water quality management. The mineral content of the water is precisely monitored and managed. Water with high mineral content is drained and fresh water added only as required, thus minimising scale build-up and reducing the energy needed to heat fresh water.
When servicing is needed, the Condair EL's design makes it easy to drain, remove and replace the disposable steam cylinders, keeping downtime to a minimum. Cleanable cylinders are also available.
An advanced touch screen control panel makes operation simple while providing detailed diagnostic reporting. A USB connection allows performance data to be downloaded into Excel and the humidifier's software to be easily updated.