MVHR Unit
The Thessla Green MVHR Units go beyond standards and have been designed to ensure your home achieves full energy efficiency, along with other important benefits.
The efficiency of a units heat recovery is reliant on balanced air flows, when this balance is achieved, the machine will work at its full potential. Control systems of most MVHR units are not performant enough to measure the actual air flows, and by setting the ventilation intensity on the control panel, the user typically sets nothing but the fan rotary speed.
Therefore, due to changes in weather conditions, wind activity, natural filter contamination and moisture condensation in the heat exchanger, the flows of supply and exhaust air constantly alter. Ventilation imbalance often exceeds 30%, therefore increasing heat losses and heating costs.
Thessla Green units avoid this issue through their Control Flow module, available to purchase separately or as part of the Energy+ and Energy++ bundles. The system reliably measures the actual supply and exhaust air flows with an accuracy of +/-3%. The results of the measurements are analysed by a processor that sets the fan rotary speed so that ventilation is balanced, regardless of the temporary atmospheric conditions and the filter load. All of the ventilation air flows through the unit where it takes part in the process of heat recovery. The indoor and outdoor air pressures are permanently equalized to ensure no air flow through leaks of the building. In this way the energy efficiency of the ventilation is always the highest possible and the heating costs are the lowest.
Thermacoustic
With Thessla Green ventilation works two times quieter. The units casing is made of 50mm closed-cell, waterproof foam, making it excellently thermally and acoustically insulated. The exposed surface area of the foam absorbs part of the acoustic wave and prevents its reflection, ultimately reducing the sound created by the ventilation system.
Thessla Green have also devised an innovative InFlow system in which there is a heat exchanger in between the fan and the supply duct. Thus, before it reaches the supply duct, an acoustic wave must pass through thousands of small ducts of the heat exchanger losing a significant part of its energy and leading to a quieter presence in your home.
Extended filter unit lifetime
CleanPadPure filters has been designed to obtain a robust, large filtration surface and the most comprehensive dust capacity. The increased number of pleats with a pre-filter use retains larger particles leading to an extension of the filter service life.
The cost of filter replacement and energy used on pumping the air through the filters are 35-50% of costs of using ventilation. Thessla Green units are equipped with M5 class two-stage filters which have 60% longer service life in comparison with the G3 and G4 class filters used in most air handling units and 5 times longer service life compared to G4 flat filters.


Season Changes – Winter
FPX Anti Freezing System
Traditionally, MVHR units limit the flow of fresh air flowing through the unit during frosty days by switching the supply fan off and significantly reducing its performance. When this happens, the premises are filled with negative pressures which cause uncontrolled inflow of cold unfiltered air through the building. Heating costs rise and the indoor air quality deteriorates.
The Thessla Green anti-freezing system invariably measures the temperature of the fresh air entering the heat exchanger. When its value drops below 1°C the FPX activates a small, precisely controlled heater which stabilises the temperature of the airflow. That is why the Thessla Green units never freeze and always function at maximum efficiency, during every season.
Summer
Bypass 100%
On summer evenings, the Thessla Green unit can completely deactivate heat recovery and use 100% of the coolness of the outdoor air to improve the thermal comfort of the building.
