Nortek Global HVAC has introduced the Reznor ZQYRA Series, a low cost, high efficiency dedicated outdoor air system (DOAS) for adding outdoor air requirements in educational, healthcare, office, retail and other light commercial spaces.
The patented ZQYRA–8 (500 to 1,100-CFM) and ZQYRA–12 (900 to 1,500-CFM) units combine control design with modulating heat pump and enthalpy wheel technology. They have among the industry’s smallest DOAS footprints and are well suited for adding outdoor air ventilation in smaller spaces for new and retrofit VRF or conventional DX air conditioning projects.
Reznor’s Z-Series Selection software expedites specification as simply as selecting an off-the-shelf system, because inputs require only basic project parameter data. Combined with the proprietary software’s capabilities, specifiers now have a choice for ventilating smaller spaces with pinpoint temperature/humidity that were previously less efficient and more costly with the industry’s predominantly oversized DOAS sizes.
The ZQYRA Series incorporates unique control functions and components in its design:
- Supplemental electric heat control uses an SCR time-proportioned modulation controller (zero to 100% control) for optimizing efficiency and pinpoint temperature control;
- Extended heat pump operational time during extremely low ambient temperatures to eliminate coil freezing and subsequent energy-intensive defrost modes;
- Z-Series Selection software calculates unit performance expectations as per inputted CFMs and the facility’s geographical temperature/humidity ranges;
- A refrigerant charge compensator that allows minimized and optimized refrigerant usage for both heating and cooling modes.
The ZQYRA Series surpasses AHRI Standard 920’s dehumidification efficiency minimum 5.2 ISMRE rating. Although both models are 3.5-tons, their silica gel, high performance enthalpy wheels’ dehumidification benefit effectively equals that of a 7-ton air conditioner. The Series also surpasses minimum requirements for ASHRAE Standards 62.1, 90.1, 189.1 and LEED project mandates for 30% more ventilation air while using 30% less building energy.
Unlike large capacity DOAS systems with options that complicate the specification process, the ZQYRA design offers a simplified approach with only basic options.
Specifiers need only to choose MERV 8 or MERV 13 filtration; corrosion-resistant coil coatings for salt water locations; and activation control options ranging from CO2, occupancy, and VOC sensors, or a manual on/off override switch; power requirements of 208/230 or 460V power. The ZQYRA Series also outperforms larger, more expensive DOAS, because of its high efficiencies– greater than 9.0 COP and greater than 17.0 EER.
Other features include:
- Functions as a stand-alone, self-contained DOAS or can be combined with packaged air conditioning systems for outdoor air supply and/or recover up to 80% exhaust air energy;
- Reznor’s durable design,pre-painted gloss-90 steel cabinets with double-wall insulation in the wet areas to minimize moisture harboring biological growth;
- Compatibility with all Building Management Systems (BMS);
- EC motor/direct drive fans;
- Heat pump’s heating mode offers a 56% energy savings versus similar sized gas-fired DOAS;
- Z-Series Selection software’s data sheet is printable for client specification presentations;
- Doesn’t require energy-inefficient defrost modes.