4.3 Control and safety devices
The unit is integrally managed by an electronic microprocessor control that, through the various installed temperature
and pressure sensors, keeps its operation within the safety limits.
All the parameters involved with control of the unit are shown in the "Control Manual" that is an integral part of the
documentation of the unit.
All the parameters involved with control of the unit are shown in the "Operating Manual" that is an integral part of the
documentation of the unit.
The manual fully describes the logic with which the checks of the unit take place during the various operating stages.
The control and safety devices are shown in the Technical Catalogue.
4.4 Principles of operation
The basic operation of these units uses a reverse vapour compression cycle to change the thermo-hygrometric
conditions of the air in the interior environment. The simplest configuration works in total air recirculation.
The refrigeration cycle allows heat to be transferred from a fluid at a lower temperature to a fluid at a higher
temperature. The Roof Top units are equipped with one or more refrigerant circuits; in cooling mode, air is cooled -
and if necessary dehumidified - by a finned coil (evaporator); the removed heat is rejected to the outside by another
finned coil (condenser).
In addition to this, the heat pump versions allow the evaporator and condenser roles to be reversed, thereby providing
the heating function.
In addition to air filtration, other functions are possible, which vary according to the configuration and the selected
options: partial air renewal, heat recovery from exhausted air, thermodynamic recovery, humidification, supplementary
heating by hot air generator, hot water coil or electric heaters, free cooling/free heating.
4.5 Structure
Depending on the sizes, the structure is made of galvanized sheet-iron coated with epoxy polyester powder at 180°C,
which makes it highly resistant to weather conditions, or of extruded aluminium alloy profiles connected with glass
fibre reinforced nylon joints.
The base and cover are made of thick, epoxy polyester powder coated, galvanized sheet-iron.
The panelling is made with 25mm thick sandwich panels consisting of a 0.5 mm thick externally pre-painted
galvanized sheet-iron casing filled with polyurethane foam to guarantee the thermal and acoustic insulation of the unit.
Alternatively, the panels are insulated with closed-cell insulating matting or with rock wool, for the "heat generator"
section. The surface of the panels in contact with the treated air is made of galvanized sheet-iron to facilitate cleaning
and sanitizing operations.
The non-removable panels are fixed to the structure with screws contained in nylon bushes with plug.
The removable panels are attached to the structure with nylon eccentrics or inserts and have handles to make them
easier to remove.
4.6 Specifications
Direct expansion air conditioner with hermetic compressors, evaporating coil with centrifugal or radial fans and
condensing coil with axial fans.
The unit is made in two sections that are joined together but functionally separate. One section is for transferring the
energy absorbed from the treated interior environment into the atmosphere. The other section is for air handling and
allows air conditioning of the confined environment to be treated.
In configurations where air exchange is envisaged, heat recovery and free cooling/free heating can be managed.
For heating, there may be a gas heat generator, or a hot water coil or a group of electric heaters.
Translation from original instructions
We reserve the right to make changes without any prior notice.
Packaged Rooftop
UATYA
30
4P645202-2