Johnson Controls’ new light commercial ACTIVA Rooftops HVAC range - smarter, smaller, more efficient

The latest generation of Johnson Controls’ ACTIVA Rooftops, a range of light commercial packaged HVAC (heating, ventilation and air conditioning) products, is still smart, but now these units are also smaller (by about 37%), quieter, more efficient (by 31%), and can converse with the building management system. In addition installation and maintenance is breeze.

Neil Cameron, General Manager of Johnson Controls Systems & Services South Africa says “A strong feature of our packaged ACTIVA Rooftops, which comes in a range of capacities from 17kW to 90kW, is the ease and simplicity built into these units. They are small-footprint all-in-one solutions that include both air handling and cooling units. And this new version of the product offers richer features with improved efficiency - a Eurovent Energy Efficiency Rating (EER) of 3.0, beating out the majority of competing solutions that have ratings of only 2.5.”

Smaller form factor, greater efficiency

The refrigerant circuit layout of the ACTIVA Rooftop product has been redesigned and high efficiency exchangers used to reduce the footprint, improving the transport and handling of the units. Adds Cameron: “Beyond improved form factor, this packaged HVAC solution offers increased energy efficiencies for users -- typically hotels, retailers, corporates, etc -- lowering the energy bill in two ways: a smart control manages the compressor and fans, allowing the unit to achieve and maintain the required level of comfort in the most efficient way; and an enthalpy wheel enables energy recovery. The last is known as ‘free cooling’, with the enthalpy wheel allowing re-use of heated exhaust air that would normally be discarded to warm the ventilated air for use within the building.”

In addition, an EC Return Fan does away with the functional challenges associated with keeping air moving through long pieces of ducting. Located in a special roof curb underneath the rooftop, it works simultaneously with the indoor fan in order to balance the amount of air supplied to and removed from the space. It is best suited for systems with high return path static pressures. The fan also incorporates EC technology and a differential pressure gauge to enable easy set up and automatically maintain the required working point in the installation.

Low noise

For hotels, corporate buildings and other structures where silent functioning of facility management equipment is desired, the low noise levels of the ACTIVA Rooftop chillers are particularly attractive. Ultra quiet fans and optimised airflow reduce the noise level, increasing comfort. Says Cameron: “New condenser fans with high technology blades and an outdoor bell reduce turbulence in the air, increase efficiency and improve noise level performance. To further reduce noise levels, compressors are mounted on shock absorbers and anti-vibration springs can be installed to avoid vibration transmissions into the building.”

N2open protocol on board

And there is one other significant change: the addition of a new Panel Control Board (PCB) board using the open standard N2open protocol enables the integration of the ACTIVA Rooftops range to the larger building management system (BMS). Notes Cameron: “The new control board keeps the same features and benefits as YKlon V3, the PCB board used previously on the larger ACTIVA Rooftop units, and adds new logic to control the tandem circuit, the new options (heat recovery, return fan) and enable communication with a BMS.”

Concludes Cameron: “Whether replacing, upgrading or installing a solution for the first time, the ACTIVA Rooftops range is a smart, eco-friendly and cost effective option for light commercial applications. It comes in a range of capacities that would suit most entry level applications and its rich features make it very attractive and highly competitive in this class of solutions.";