VENTS VUT WH

Description

Air handling units VUT WH with water heater are the complete air handling units designed to provide both supply and exhaust ventilation with air filtering and heat recovery. The exhaust air energy is used to heat up the supply fresh air through the heat exchanger. All the models are designed for connection with Ø 125, 150, 160, 200, 250, 315 mm round ducts.

Modifications

VUT WH – a range of compact energy saving air handling units (AHU) equipped with supply and exhaust centrifugal fans, cross-flow heat recovery elements, water or glycol heating coils and air filters.

Casing

The casing is manufactured from aluminum-zinc compound with 25 mm thick mineral wool heat- and sound-insulating layer.

Filter

Two incorporated G4 panel filters for extract air ventilation and F7 filters for supply air ventilation are supplied with the unit.

Fans

The units are equipped with supply and exhaust centrifugal double-inlet fans with forward curved blades and built-in thermostat with automatic restart. The electric motors and impellers are dynamically balanced in two planes. The ball-bearings used with motors are designed for at least 40 000 hours operation and are maintenance-free.

Heat exchanger

The heat exchangers have high efficiency and are manufactured from aluminium plates. The unit is also equipped with the drain pan for condensate drainage.

Heater

The water heater at outlet from the heat exchanger is designed for warming up of supply air up to the set level if heat recovery is not enough to attain the set supply air temperature. The water heaters are designed for max. operating pressure 1.0 MPa (10 bar) and max. heat medium operating temperature 95 °C.

Automation and control system

The unit incorporates an integrated automation and control system with a multi-functional control panel with LCD display. The standard delivery set includes 10 m connection cable for connection to the remote control panel. The unit has the freezing protection function to prevent the heat exchanger freezing by means of actuating the bypass damper and controlling water heater. As the temperature sensor warns of the freezing danger, the bypass air damper is opened and the intake air is directed through the air duct beside the heat exchanger. As the heat exchanger is warmed the supply air temperature rises up to the set level while passing through the heater. Meanwhile the warm extract air warms up the heat exchanger. After the freezing danger is no longer imminent, the bypass damper shuts the bypass duct and the unit reverts to the standard operation mode.

VUT WH control and protection functions

• control from the control panel: switching on/off, three-speed fan selection, selecting heating/cooling modes (if connected to duct heater); room temperature display;
• maintaining supply air temperature set from the control panel by controlling the circulation pump and actuating the heat medium regulating valve; input from the heat medium flow switch (pump alarm);
• safe start-up/ shutdown of the fans, warming up of the water heater before start-up; return heat medium temperature control when the fan is off;
• freezing protection of the water heating coils by the exhaust temperature sensor and the return heat medium temperature sensor;
• control of the compressor and condensing unit of the water cooler by the room temperature sensor (for the models equipped with a duct air cooler);
• actuating the external air dampers with a return spring;
• unit operation according to week schedule (set at the system setup);
• unit shut down at signal from the fire alarm system;
• smooth bypass damper control in the bypassing mode to prevent the heat exchanger freezing.

Accessories for air handling units:

SF

Mounting

The unit is designed for indoor mounting. While mounting the unit provide the correct condensate collection and drainage. Access for the unit servicing and filter cleaning is from the side panels on the left from supply air side.

Access for the unit servicing for VUT 1500 WH and VUT 2000 WH is available from the left or right side panels depends on order code.

Options

For attenuation of sound generated by the fans it is recommended to install the duct silencer (refer SR) from inside before the unit. For vibration absorbing it is recommended to install the flexible antivibration connectors (refer VVG) on both sides of the unit. The mixing units USWK are recommended for smooth supply air temperature regulation in the units equipped with water heaters. The mixing unit USWK with three-way heat medium regulating valve and circulation pump provides smooth heating capacity regulation and minimizes the water heater freezing danger.