VENTS VUT EH Series Heat Recovery Air Handling Unit

Introduction

This user's manual is intended for technical, maintenance, and operating staff. It contains essential information regarding the purpose, technical details, operating principle, design, and installation of the VUT 350/500/530/600/800/1000/1500/2000 EH units and their modifications. Personnel must possess theoretical and practical training in ventilation systems and adhere to workplace safety rules and applicable construction norms and standards.

The Company reserves the right to modify product specifications and design at any time. Reproduction or transmission of any part of this publication without prior written permission is prohibited.

Safety Requirements

• Please read the user's manual carefully before installing and operating the unit.
• Observe all manual requirements and applicable local/national construction, electrical, and technical norms and standards.
• Pay close attention to warnings in this manual, as they contain vital personal safety information.
• Failure to follow safety precautions may result in injury or unit damage.
• Keep the manual for the unit's entire service life.
• Transfer the manual to the new operator when transferring unit control.

Unit Installation and Operation Safety Precautions

• [Disconnect power] Disconnect the unit from power mains prior to any installation operations.
• [Unpack with care] Unpack the unit with care.
• [Grounding required] The unit must be grounded.
• [Follow tool safety] While installing the unit, follow the safety regulations specific to the use of electric tools.

• [Do not alter cable] Do not change the power cable length, bend, damage, or place foreign objects on it.
• [Use safe equipment] Do not use damaged equipment or cables when connecting to power mains.
• [Dry hands] Do not touch unit controls or perform maintenance with wet hands.
• [Child safety] Do not allow children to operate the unit.
• [No flammables] Do not store explosive or highly flammable substances near the unit.
• [Do not open during operation] Do not open the unit during operation.
• [Do not block ducts] Do not block the air duct when the unit is switched on.
• [No objects on unit] Do not sit on the unit and avoid placing foreign objects on it.

• [Keep cable from heat] Do not lay the power cable near heating equipment.
• [Respect temperature limits] Do not operate the unit outside the specified temperature range or in aggressive/explosive environments.
• [Water protection] Do not wash the unit with water; protect electrical parts from water ingress.
• [Disconnect for maintenance] Disconnect the unit from power mains prior to any technical maintenance.
• [Report issues] If the unit generates unusual sounds, odor, or smoke, disconnect it from power supply and contact the Seller.
• [Fire safety] Do not direct airflow towards open flame or ignition sources.
• [Check mounting] Periodically check mounting security during continuous operation.
• [Intended use only] Use the unit only for its intended purpose.

[Disposal] The product must be disposed of separately at the end of its service life. Do not dispose of the unit as unsorted domestic waste.

Purpose

The unit is designed for continuous mechanical air exchange in various spaces like houses, offices, hotels, cafes, and conference halls. It recovers heat energy from extracted air to warm the incoming fresh air stream, contributing to energy efficiency. The unit is not intended for spaces with high humidity such as swimming pools or saunas.

The unit is a component part and requires integration into a larger system; it is not designed for stand-alone operation. It is rated for continuous operation.

Transported air must not contain flammable or explosive mixtures, chemical vapors, sticky substances, fibrous materials, coarse dust, soot, oil particles, or environments conducive to hazardous substances (toxic substances, dust, pathogenic germs).

Important Safety Warnings:

• The unit should not be operated by children or persons with reduced physical, mental, or sensory capacities, or those without appropriate training.
• Installation and connection must be performed only by properly qualified personnel after appropriate briefing.
• The unit installation location must prevent unauthorized access by unattended children.

Delivery Set

Designation Key

The unit model designation, e.g., VUT 350 E H, is interpreted as follows:

• VUT: Heat recovery air handling unit
• 350: Rated air flow in m³/h
• E: Indicates the presence of an electric heater
• H: Spigot orientation (Horizontal)

Technical Data

The unit is designed for indoor application with ambient temperatures ranging from +1 °C to +40 °C and relative humidity up to 80%. To prevent condensation on internal walls, the casing surface temperature must be 2-3 °C higher than the dew point temperature of the transported air.

The unit is rated as a Class I electrical appliance.

Hazardous parts access and water ingress protection rating:

• IP22 for the unit connected to the air ducts.
• IP44 for the unit motors.

Unit design is subject to continuous improvement, so models may differ slightly from descriptions in this manual.

Overall Dimensions of the Unit [MM]

The following diagrams illustrate the overall dimensions for different model series. Specific measurements are provided in the tables below.

VUT EH 350...600 Series Dimensions

Diagram shows a rectangular unit with circular spigots on one side and a flat panel on the other. Labeled dimensions include A, B, C, D, E, F, G, H, I, K.

VUT EH 800...2000 Series Dimensions

Diagram shows a larger rectangular unit with circular spigots on one side and a flat panel on the other. Labeled dimensions include A, B, C, D, E, F, G, H, I, K, L, M.

Technical Data Table

Design and Operating Principle

The unit operates by facilitating mechanical air exchange. Warm, stale extract air from a room is drawn into the unit, filtered, and then passed through a heat exchanger. An extract fan exhausts this air outside. Simultaneously, clean, cold outdoor air is drawn in, filtered, and directed through the same heat exchanger. This process transfers heat energy from the warm extract air to the cooler intake air, pre-warming it before it is supplied to the room by a supply fan. This heat recovery system minimizes thermal energy losses and reduces heating expenses.

The unit features a frame structure constructed from six rigidly fixed sandwich panels: 25 mm thick for VUT 350-600 EH models and 50 mm thick for VUT 800-2000 EH models. These three-layer panels consist of two galvanized sheets with integrated heat and sound insulation (mineral wool).

The air handling unit is equipped with quick-detachable, specially sealed service panels for easy access during maintenance. The terminal block is located either in a terminal box (for VUT 350-600 EH) or within the control unit (for VUT 800-2000 EH). Power and ground cables connect via sealed lead-ins to the terminal block.

Diagram Description: The operating principle diagram visually depicts the airflow paths. Arrows indicate warm extract air entering from the left, passing through the heat exchanger, and exiting via the extract fan. Simultaneously, fresh intake air enters from the right, passes through a filter, then the heat exchanger, and is supplied to the room via the supply fan.

Components

The following diagrams illustrate the internal layout and key components of the VUT EH units.

VUT 350...600 EH Component Diagram

Diagram shows a side view of the unit with numbered components: 1. Supply fan, 2. Extract fan, 3. Heat exchanger, 4. Supply air filter, 5. Extract air filter, 6. Drain pipe, 7. Electric heater, 8. Bypass, 9. Wall control panel, 10. Control unit, 11. Drain pan, 12. Quick-detachable panels, 13. Terminal box (VUT 350...600 EH).

VUT 800...2000 EH Component Diagram

Diagram shows a side view and a front view of the unit with numbered components: 1. Supply fan, 2. Extract fan, 3. Heat exchanger, 4. Supply air filter, 5. Extract air filter, 6. Drain pipe, 7. Electric heater, 8. Bypass, 9. Wall control panel, 10. Control unit, 11. Drain pan, 12. Quick-detachable panels.

Basic Complete Set

• Wall control panel connected via data cable to the unit's integrated control system.
• Supply and extract fans with forward-curved blades and maintenance-free external rotor motors with built-in overheating protection.
• Plate cross-flow heat exchanger.
• Electric heater with overheating protection (two integrated thermal switches: one safety type at +50 °C with automatic reset, and one emergency type at +90 °C with manual reset).
• Supply filter (fine filtering G4).
• Extract filter (coarse filtering G4).

Mounting and Set-up

Important: READ THE USER'S MANUAL BEFORE INSTALLING THE UNIT.

The unit can be suspended on threaded rods fixed in dowels or rigidly mounted on a horizontal plane.

Mounting on a Horizontal Plane

Diagram Description: Illustrates unit mounting on a horizontal surface. An example shows a threaded rod connection with a nut, washer, vibration-absorbing rubber, and another nut and lock nut.

Ensure sufficient access for maintenance or repair work during mounting.

Safety Precautions for Mounting

• The unit must be mounted to a rigid and stable structure, considering its weight (refer to technical data). Use anchor bolts for suspension.
• Verify the mounting structure's load capacity before installation. Reinforce if necessary.
• Ensure the construction strength and surface rigidity are adequate to prevent resonance and abnormal noise/vibration.
• Provide adequate service space and an access door in the ceiling for inspection and maintenance of filters, heat exchanger, and fans.
• Install M8 anchor bolts, securing them with nuts and washers.
• Before mounting, check the casing for any foreign objects like foil or paper.

Resonance Prevention: If unit mounting bolts are too short, abnormal noise and ceiling resonance may occur. If noise is present at the spiral air duct joint, replace it with a flexible duct. Flexible anti-vibration connectors are also recommended.

For optimal performance, install a straight 1-meter duct section on both sides of the unit.

The unit must be equipped with a protective grille or device with a mesh width not exceeding 12.5 mm to prevent unauthorized access to the fans.

Condensate Drainage

Diagram Description: Shows the condensate drain pipe connected to a U-trap, which then connects to a pipe leading to the sewage system. A minimum slope of 3° is indicated for the drain line.

• Do not connect multiple drain pipes from different units to a single U-trap.
• Direct condensate drainage without connection to a drain system is not allowed.

Connection to Power Mains

Safety Warning: POWER OFF THE POWER SUPPLY PRIOR TO ANY OPERATIONS WITH THE UNIT. THE UNIT MUST BE CONNECTED TO POWER SUPPLY BY A QUALIFIED ELECTRICIAN. THE RATED ELECTRICAL PARAMETERS ARE ON THE MANUFACTURER'S LABEL. ANY TAMPERING WITH INTERNAL CONNECTIONS IS PROHIBITED AND WILL VOID THE WARRANTY.

The unit connects to 1~230 V/50 Hz or 3~400 V/50 Hz power mains using insulated electric conductors. Wire cross-section selection must be based on maximum load current, conductor temperature, wire type, insulation, length, and installation method.

The external power input requires an automatic circuit breaker (QF) in the stationary wiring for overload or short-circuit protection. The circuit breaker must be easily accessible for emergency shutdown. Its trip current should exceed the unit's maximum consumption. The circuit breaker is not included in the delivery set.

Single-phase Power Mains (VUT 350...600 EH)

Diagram Description: Shows a single-phase connection diagram for 230V/50Hz. Terminals are labeled L (Line), N (Neutral), and PE (Protective Earth). An automatic circuit breaker (QF) is shown before the connection (X1) to the air handling unit.

Three-phase Power Mains (VUT 800...2000 EH)

Diagram Description: Shows a three-phase connection diagram for 400V/50Hz. Terminals are labeled L1, L2, L3 (Lines), N (Neutral), and PE (Protective Earth). An automatic circuit breaker (QF) is shown before the connection (X1) to the air handling unit.

Technical Maintenance

Safety Warning: DISCONNECT THE UNIT FROM POWER SUPPLY BEFORE ANY MAINTENANCE OPERATIONS!

Maintenance operations are recommended 3-4 times per year.

1. Filter Maintenance (3-4 times per year): Dirty filters increase air resistance and reduce airflow. Clean filters using a vacuum cleaner or replace them. Contact the Seller for new filters. Remove filters by unscrewing the front panel.
2. Heat Exchanger Maintenance (once per year): Dust accumulation can reduce heat recovery efficiency. Clean the heat exchanger using compressed air or a vacuum cleaner after removing the front panel. Re-install after cleaning.
3. Fan Maintenance (once per year): Dust can accumulate inside fans, reducing performance. Clean fans with a soft cloth, brush, or compressed air. Avoid water, aggressive solvents, or sharp objects.
4. Condensate Drainage System Maintenance (4 times per year): Check drain line operation by filling the drain pan with water. Clean the U-trap and drain line if necessary to prevent clogging by extract air particles.
5. Supply Air Flow Control (twice per year): Check the supply duct grille for blockages (leaves, objects) that reduce performance. Clean as required.
6. Ductwork System Maintenance (once in 5 years): Even with regular maintenance, dirt can accumulate in ducts, affecting air quality and capacity. Duct maintenance involves regular cleaning or replacement.
7. Control Unit Maintenance (if necessary): Access the control unit inside the casing by removing the panel's fixing screws and lifting the lid.

Troubleshooting

Storage and Transportation Regulations

• Store the unit in its original packaging in a dry, ventilated premise with temperatures between +5...+40 °C and relative humidity up to 70%.
• The storage environment must not contain aggressive vapors or chemical mixtures that could cause corrosion or deformation of insulation and sealing.
• Use suitable hoisting machinery for handling and storage to prevent damage.
• Follow handling requirements applicable to the cargo type.
• The unit can be transported by any mode of transport in its original packaging, provided it is protected against precipitation and mechanical damage. Transport only in the working position.
• Avoid sharp blows, scratches, or rough handling during loading and unloading.
• Before initial power-up after transportation at low temperatures, allow the unit to warm up to operating temperature for at least 3-4 hours.

Manufacturer's Warranty

The product complies with EU norms and standards for low voltage and electromagnetic compatibility, including Directives 2014/30/EU, 2014/35/EU, and CE-marking Directive 93/68/EEC.

The manufacturer warrants normal operation for 24 months from the retail sale date, provided transportation, storage, installation, and operation regulations are observed. Warranty repair covers elimination of faults caused by the manufacturer during the guaranteed period, free of charge.

Warranty Repair Exclusions

• Routine technical maintenance.
• Unit installation/dismantling.
• Unit setup.

To claim warranty repair, provide the unit, user's manual with purchase date stamp, and proof of purchase. The unit model must match the manual.

Cases Not Covered by Warranty

• Failure to submit the complete delivery package or missing components.
• Mismatch of unit model/brand with stated information.
• Failure to perform timely technical maintenance.
• External damage to casing or internal components caused by the user.
• Redesign or engineering changes to the unit.
• Use of unapproved assemblies, parts, or components.
• Unit misuse.
• Violation of installation or control regulations.
• Connection to power mains with incorrect voltage.
• Unit breakdown due to voltage surges.
• Unauthorized repair or modification by the user or third parties.
• Expiration of the warranty period.
• Violation of transportation or storage regulations.
• Wrongful actions by third parties.
• Breakdown due to force majeure (fire, flood, earthquake, war, blockades).
• Missing seals.
• Failure to submit the user's manual with purchase date stamp or proof of purchase.

Adherence to stipulated regulations ensures long and trouble-free operation. Warranty claims are subject to review upon presentation of the unit, payment document, and user's manual with the purchase date stamp.

Certificates

Certificate of Acceptance

Seller Information

This is to certify acceptance of the complete unit delivery with the user's manual. The warranty terms are acknowledged and accepted.

Customer's Signature: _________________________

Installation Certificate

The VUT_____EH unit is installed pursuant to the requirements stated in the present user's manual.

The unit has been installed in accordance with all applicable local and national construction, electrical, and technical codes and standards. The unit operates normally as intended by the manufacturer.

Signature: _________________________

Seller's Stamp

Installation Stamp

Warranty Card

Seller's Stamp