—— Product Description ——
Improve indoor air quality with a DOAS providing the ventilation, heat recovery and dehumidification that your system needs.
Withair® Integrated Outdoor Air System combines a dedicated outdoor air system (DOAS) with chilled-water, sensible-cooling terminal units to deliver a flexible, energy efficient solution to provide comfortable spaces and simplify maintenance.
DOAS are designed to provide ventilation for the most demanding applications. All series 100% outdoor air units feature high capacity DX coils and efficient scroll compressors, making them ideal for schools, hotels, offices and other buildings that require efficient and reliable ventilation.A DOAS is a special HVAC system in which its purpose is to treat outside air for ventilation of air in a space or to an ancillary cooling and heating system. A common application is for the use of exclusively treating outside air in order to achieve a high indoor air quality. Poor indoor air quality can lead to negative impacts on the building occupants, indoor components, and overall condition of the building.
Withair® DOAS is a factory-assembled packaged unit that can operate within a broad range of ambient conditions and introduce ventilation air into a building at neutral conditions. The unit can be configured to utilize straight cooling, gas/electric/hot water heating, or an air/water source heat pump. It consists of matched refrigeration and air moving components (system controls, compressor(s), evaporator section, condensing section and fan(s)) designed to cool, heat, and/or dehumidify 100% outside air and/or mixed air. The unit may be provided with several different options and controls to meet various application requirements including optional hot gas reheat and liquid subcooling, energy recovery wheel, and supplemental heat (gas, electric, or hot water) with variable air volume delivery.
—— The Key Advantages Include ——
● All model sizes share a common, compact cabinet in a single footprint for on-site flexibility.
● Installation time and costs are reduced by easy power and control wiring. All units are factory-wired, charged and tested prior to shipment.
● Delivers clean, dehumidified outside air in all weather and climate conditions.
● Compressor is internally protected against high pressure and temperature.
● Units are engineered and built to be among the quietest models.
● Up to 100% outside air.
● Elliptic tube high efficiency heat exchanger and without air stripping, the heat transfer can be maximized.
● Convertible airflow design means no panel cutting is required, and no accessory panel is necessary.
● Heat exchangers are corrosion-resistant, with aluminized steel tubular construction for durability and long service life.
● Post-purge induced draft combustion exhausts combustion products from the heat exchanger to prolong heat exchanger life.
● Secured service access ports are protected, externally mounted and reusable on both high and low lines.
● Complete line of field-installed accessories, including propane and high altitude conversion kits, economizers, single- and dual-enthalpy sensors and more.
● Heat exchangers are built in and with filter design, corrosion-resistant, with aluminized steel tubular construction for durability and long service life.
● Evaporator coils are constructed with grooved copper tubes and enhanced for construction to improve heat transfer.
● Condenser coils are constructed of MicroChannel aluminum tubing and aluminum fins for durability and long-lasting efficient operation.
● Control terminal board facilitating simple safety circuit troubleshooting and simplified control box arrangement.
● Access panels with easy grip handles and tool-less filter access door.
● Strong heat capacity in winter,because of the use of exhaust heat recovery, the heat system is guaranteed at -12.5℃, supply air temperature can be up to 20.5℃.
● Belt drive evaporator-fan motor and pulley combinations available on all three phase models to meet any application.
● Dependable time/temperature defrost board and logic.
● The unit adopts centrifugal fan as the exhaust fan, low noise and high efficiency.
● No cross contamination- No cross contamination- because it is completely separate structure, unit is absolutely no cross contamination, and other heat recovery unit, plate heatexchanger and heat recovery wheel, due to the influence of structure will produce cross-contamination, so unit is particularly suitable for hospital use.
● Flexible Design- The DOAS unit and its associated ductwork are typically sized for only the minimum ventilation airflow required, in turn requiring less ceiling plenum height and allowing for more usable space inside the building. Reconfiguring a zone often requires moving only the downstream flex duct and supply-air diffusers; the sensible-cooling terminal units and water piping often do not need to move. And, the sensible-cooling terminal units can be equipped with either a hot-water coil or electric heater, if necessary.
● Comfortable Spaces- Each terminal unit is controlled by a zone temperature sensor, and contains its own cooling coil and (optionally) either a hot-water coil or electric heater, allowing each zone to receive cooling or heating as needed. Dehumidification is provided by the centralized, DOAS unit; and, when equipped with a humidity sensor, the terminal unit actively adjusts dehumidified airflow from the DOAS unit to limit space humidity, ensuring a comfortable environment..
● Low Maintenance- No condensation occurs at the zone-level terminal units, meaning no drain pans to clean and no condensate drain traps and piping to install and maintain. And, since the cooling coil in each terminal unit operates dry, an optional upstream filter is available, but not required.
● Unique product structure design- In Summer, the cool condenser is cooled by cold return air in summer, and there is no overheating phenomenon; In Winter, the evaporator is heated through the hot return air, without the risk of frost crack and frosting at low temperature.
Ceiling type (air flow:350~5000m³/h)---Indoor location
Floor type (air flow:1200~10000m³/h)---Indoor location
Floor type (air flow:1500~15000m³/h)---Outdoor location
1.Cooling condition: outdoor air inlet dry bulb temperature 33℃, wet bulb temperature 28℃, return air (exhaust air) dry bulb temperature 27℃,wet bulb temperature 19.5℃.
2.Heating condition: outdoor air inlet dry bulb temperature 7℃, wet bulb temperature 6℃, return air (exhaust air) dry bulb temperature 20℃,wet bulb temperature 13.8℃.
3.Wet film humidifier, heat recovery and filter are for options.
4. All specifications are subject to change without prior notice, please refer to nameplates for the most accurate specifications
Packaging & Transportation
● Four steps of pakacges, plastic film, foam, carton and plywood for stable transporation.
Withair® provides two styles package for different transporation modes:(1). St andard package(free of charge): unit is wrapped with plastic film, foam and carton, which is suitable for container shipment & a few transshipment cargo;