echanical Ventilation with Heat Recovery, or MVHR, systems are widely recognized for their ability to improve indoor air quality while reducing energy loss in modern buildings. By extracting stale air from wet rooms like kitchens and bathrooms and simultaneously supplying fresh filtered air to living areas, MVHR units maintain a balanced and comfortable environment. They work by transferring heat from outgoing air to incoming air through a heat exchanger, which minimizes energy wastage. However, like any mechanical system, MVHR units are prone to faults and MVHR repairs may require repairs to maintain optimal performance. Issues can arise from worn components, blockages, or general wear and tear, and addressing them promptly is essential to prevent reduced efficiency or indoor air problems.
One of the most frequent causes of MVHR malfunction is clogged or dirty filters. Filters capture dust, pollen, and other airborne particles, and over time they become saturated. This restricts airflow, putting extra strain on fans and reducing the system’s ability to maintain temperature and humidity levels. In addition to the immediate impact on comfort, a blocked filter can accelerate wear on other components, making repairs more complex. Regular inspection and timely replacement of filters are critical maintenance practices that can prevent more serious breakdowns.
The heat exchanger core, the heart of the MVHR system, is another component susceptible to issues. Dust, moisture, and other debris can accumulate, reducing heat transfer efficiency and causing potential cross-contamination of fresh and stale air. Improper sealing during installation or after service can also allow leaks, compromising indoor air quality. Repairing a heat exchanger requires careful handling, as any damage or misalignment can significantly affect performance. In some cases, deep cleaning or replacement of the core is necessary to restore full functionality.
Fan motors in MVHR units operate continuously and can experience mechanical or electrical problems over time. Worn bearings, loose wiring, or motor failures can cause noise, vibration, or complete system shutdown. Technicians often diagnose these problems using specialized tools and may recommend motor replacement if repairs are not cost-effective. Proper fan operation is vital because it ensures that the system maintains balanced airflow throughout the building, preventing issues such as condensation or uneven heating.
Condensate management is another area where MVHR systems can require attention. As air passes through the heat exchanger, moisture is naturally extracted and must drain away efficiently. Blocked condensate pipes, poor installation, or freezing in colder climates can cause water buildup inside the unit, potentially damaging components and creating hygiene concerns. Repairs may involve clearing blockages, adjusting the drainage path, or insulating pipes to ensure proper water flow.
Modern MVHR systems often include sensors and electronic controls that regulate airflow, humidity, and boost modes based on occupancy or environmental conditions. When these sensors fail, the system may not respond correctly, leading to poor air quality or excessive energy consumption. Repairs can involve recalibrating sensors, updating software, or replacing control boards. Ensuring the electronics function properly is critical to maintain the energy efficiency and reliability of the system.
Ductwork integrity is equally important for effective MVHR operation. Flexible ducts can become crushed or disconnected, and rigid ducts may develop leaks, reducing system efficiency. Small leaks can disrupt the balance between supply and extract air, potentially allowing unfiltered air to enter the building. After any repair or adjustment, professionals typically rebalance the system to guarantee even airflow throughout the property. Properly maintained ducts, along with functional fans and heat exchangers, keep the system operating as designed.
Regular maintenance is the key to minimizing the need for major MVHR repairs. Routine cleaning, filter replacement, and inspection of fans, heat exchangers, and ducts can extend the system’s life and ensure consistent performance. While some basic maintenance can be done by homeowners, technical repairs should always be handled by trained professionals. With proper care, MVHR systems continue to provide fresh, filtered air, maintain energy efficiency, and protect the health of building occupants.