Compact AHU OPTIMAX
Coming across our customers' expectations, Juwent has developed a new series of types of air handling units conforming with higher and higher European Union requirements for energy efficiency and environmental protection. The basic goals of the new series of types is to minimize costs of electric energy consumption and costs related to heat energy production. Use of the most recent solutions in heating technology as highly efficient rotary heat exchangers enables heat energy to be recovered from air being exhausted with the capacity conforming with Regulation of the Commission (UE) no. 1253/2014 on implementation of Directive of the European Parliament and and the Council 2009/125/EC regarding setting of eco-design requirements for ventilation systems.
Series of types includes 5 sizes of units within the capacity from 500 up to 18,000 m3/h. Designed for use in ventilation and air conditioning systems, both in public utility and residential as well as industrial buildings.
The applied subassemblies enable:
filtering of the fresh air and the air being removed from the handled rooms;
- all year long energy recovery which allows for fresh air pre-heating in winter, and fresh air pre-cooling in summer;
- heating of ventilation air in heating season;
- cooling of ventilation air in summer;
- silencing of noises generated by operating fan assemblies.
Series of types includes:
- base section;
- water heating coil section;
- common water heating and water cooling coil section;
- common water heating and freon evaporation coil section;
- silencing section.
The section has been designed as air-supply and exhaust type in double-deck configuration. The section comprises: casing, dampers, filters, fans, rotary heat exchanger, condensate tray.
Casing construction bases on the spacious frame made of aluminium profile. Wall, roof and base planes are heat insulation panels made of 45 mm thick mineral. Inside the panel special reinforcements are used thanks to which the whole structure is stiff and strong. At the service side there is hinged inspection door closed using clamps with thumb screws. In order to ensure proper tightness of the whole casing the panels are sealed with special adhesive, and inspection door is provided with double seals.
To keep tightness between base section and other sections, air supply inlets and outlets have insulation on their circuits. Additionally, in corners of the casings at air supply inlet and outlet sides steel section connectors with oblong holes are fitted. When connecting sections, this solution enables to level any slight unevenness in surface for setting the unit both vertically, and horizontally.
To ensure the units are set properly on the ground, in casings of base sections in 10, 20, 30 sizes, load-bearing feet are provided. In other sizes the casing is equipped with load-bearing base with handles for vertical transportation, made from galvanized steel section.
Base sections are equipped with 2 multi-plane dampers with seals. They are mounted inside the casing. One is located at the fresh air inlet side, and the other at the inlet of the air being exhausted from rooms. Thanks to such solutions damper actuators are also located inside the casing, and protected against the precipitation.
Base sections are equipped with fine M5 panel filters at the air supply side and the removed air side, and with very fine F7 bag filters at the air supply side. Between each filter section and along guides, special seals are applied. Number of filter sections and their size depends on the unit size.
In base sections centrifugal fan with direct drive powered by AC 3x400V motors have been used. Depending on unit size, a total of 2 or 4 fans are used. Rotors in all unit sizes, except 10, are made of plastic.
Rotary heat exchanger
In base sections, high-efficiency condensing rotary heat exchangers are applied. In order to minimize air leaks between air supply and exhaust parts, flexible circumferential seal and horizontal brush seal have been applied. The rotor is driven by a belt transmission with 3x230 V powered motor with cylindrical gearmotor.
Under the rotary heat exchanger rotor, in the casing floor a tray made of stainless steel has been used to collect condensate with condensate drains, provided outside the casing. On the tray perimeter, between the tray and the casing silicone seals are fitted.
The units must not be used when:
- the air being transferred may contain solid, pasty, fibre and aggressive substances causing corrosion or decomposition of zinc, copper, steel and aluminium;
- temperature and humidity values for external air in summer or winter are outside limits determined for Europe;
- operation in maritime or tropical climate is expected;
- the air is excessively dusted and involves very often replacement of air filters within the unit;
- power supply of water heater is unreliable for a long period of time that even operable automatic equipment would not protect the exchangers against freezing and possible resulting losses (damage to the heating coil, damages due to room flooding).