Designing an MVHR System for your Home

Designing an MVHR (Mechanical Ventilation with Heat Recovery) system for your home can be a daunting task, but with careful planning and design considerations, it can be an effective way to improve indoor air quality and reduce energy consumption. In this article, we’ll explore key design considerations for MVHR systems, including system sizing, ductwork layout, ventilation rates, and more, to help you design an effective and efficient MVHR system that meets your home's needs.

System Sizing and Heat Recovery Efficiency

MVHR systems come in various sizes, and selecting the right size is critical to ensure optimal performance and energy efficiency. To determine the correct sizing, factors such as room size, insulation levels, and occupancy rates need to be taken into account. The system size also impacts heat recovery efficiency, which is the ability of the system to extract heat from stale air before it's expelled from the home. The greater the system size, the higher the heat recovery efficiency, which ultimately translates to reduced energy consumption and lower heating bills.

Ductwork Layout and Design

The layout and design of ductwork are essential considerations in designing any ventilation system, and MVHR systems are no exception. The ductwork layout should be optimized to ensure an even distribution of fresh air throughout the home while effectively extracting stale air from moisture-laden areas. Considerations such as the location of the ventilation unit, the length and diameter of ducts, and the use of trunk-and-branch vs. radial systems all need to be evaluated to ensure optimal performance.

Ventilation Rates and Indoor Air Quality

Ventilation rates play a critical role in ensuring optimal indoor air quality, so it's essential to design the MVHR system to meet the specific ventilation needs of your home. Factors such as occupancy rates, room size, and the presence of moisture-producing areas such as kitchens and bathrooms should be taken into account when determining ventilation rates. The goal is to provide enough fresh air to maintain a healthy living environment without sacrificing energy efficiency.

Filtration and Pollutant Control

Proper filtration is essential to ensure the air supplied to the home is clean and healthy. Choosing the right filter type and placement is critical in preventing pollutants such as pollen, dust, and other allergens from circulating through the home. A pre-filter designed to remove larger particles is typically the first line of defense, followed by higher-efficiency filters to capture smaller particles. Selecting the appropriate filter classification is important as well., the higher the filter classification, the better it is at removing pollutants.

Moisture Control and Humidity Levels

Controlling moisture levels in the home is essential in preventing issues such as mold growth, condensation, and subsequent damage to building materials or health concerns. MVHR systems can help to manage moisture levels by effectively extracting stale air from moisture-laden areas, such as kitchens and bathrooms. The heat recovery process also helps to reduce the risk of condensation, as preheating the incoming fresh air reduces temperature differences that can lead to condensation.

Acoustic Design and Noise Reduction

MVHR system designs should address noise considerations for optimal performance and occupant comfort. The sound levels produced by fans and ductwork can be disruptive, so acoustics and noise reduction should be key design considerations. Strategies such as insulating ductwork and using low-noise fans can help minimize noise levels, ensuring a peaceful and comfortable living environment.

Monitoring and Maintenance

MVHR system monitoring and maintenance are essential for ensuring optimal performance and avoiding potential issues. Advanced MVHR systems come with monitoring sensors that provide real-time information on air quality, energy consumption, and more. This information can be used to optimize system performance and ensure optimal energy efficiency. Maintenance requirements typically involve cleaning the heat exchanger and replacing filters, but the frequency and type will depend on the specific system design, use, and location.

In conclusion, designing an MVHR system for your home requires careful planning, evaluation of the specific home's needs, and an understanding of which features and design factors are essential to enable optimal performance and energy efficiency. By considering factors such as system sizing, ductwork layout, ventilation rates, filtration, moisture control, acoustic design, and monitoring/maintenance, you can design an effective MVHR system that optimizes your home's indoor air quality, energy consumption, and overall comfort levels.