What is the Difference Between Dampers and Louvres?
Dampers and Louvres are both very important parts of the wider HVAC system. Whilst the two can look similar to the untrained eye, they do separate (but equally important) jobs. What is a Damper? A Damper is a valve that stops or regulates the flow of air inside a duct . There are a number of different types of Damper, each for specific uses. Fire Dampers, as we've discussed in our knowedge hub article about fire dampers, impede the spread of fire and smoke in the event of a fire. Volume Control Dampers help to manage the flow of air in a building as part of the HVAC system. Non return Dampers are opened by airflow, and closed by gravity, and are seen in both commercial and residential properties, these Dampers are used to permit air to flow in one direction, but not the other, therefore minimising heat loss from within a building when a system is inactive. Non-Return Dampers if set up correctly have no need for a motor, or manual input. True Volume Control Dampers are used for balancing or throttling throughflows, and can be either motorised or manual. Examples of True Volume Control Dampers can be found here S900B, S800B - an offshoot of this type of Damper is a Shut Off Damper that offers a tighter seal in a closed position, these can also be made to be manual or motorised. Examples of Shut Off Dampers can be found on our site, S900C and S800C. Unlike Fire Dampers, which are almost always made of steel in UK Volume Control Dampers, Non Return Dampers and Shut Off Dampers can be found in a much wider range of materials, such as aluminum and uPVC. Motorised Dampers are most often electrical, but can also be pneumatic. Electrical motors are available with a range of features to tailor the specific use of a Damper. Modulation as an example can allow control of positions between open and closed going beyond a simple shut off or isolation and enables precise control of the flow rate. Motorised Dampers can also be automated to be controlled by thermostats as part of a larger HVAC system. Spring Return Dampers can be used to ensure the blades return to a fail position in an instance of loss of power, or hydraulic pressure. For more detailed information on specific types of Dampers, please look to our Knowledge Hub for articles on further applications and subtypes. What are Louvres? Louvres, on the other hand, are positioned on the exterior of the building to allow fresh air through and protect the HVAC system against water, dirt and debris ingress, such as rain and leaves. Traditionally, they sit on exhausts or air intakes and have fixed blades which do not close. This means that, if air shut off is required, a secondary damper is required. For example, HVC’s NCA S800C – Heavy duty shut-off. Differences Between Dampers and Louvres Louvres are designed to prevent water, dirt and debris ingress; dampers are designed to manage airflow and impede the spread of fire and smoke (in the case of a Fire Damper). Whether controlled by gravity or motor, the blades on a damper can open or close depending on the requirements. The blades on a louvre are stationary. Contact HVC Today For more information about our external weather louvres, dampers, or any of the products in our range, get in touch with HVC today. Our dedicated and experienced team will be happy to answer any questions you may have.
What is a Sand Trap Louvre?
Sand Trap Louvres, as their name suggests, are a type of louvre designed to impede dust, sand and other aggregates from entering a HVAC system. In this article, we’ll be going over the specifics of where the Sand Trap Louvre should be installed, why they’re necessary, and how they work. Where Are Sand Trap Louvres Installed? Normally, they are installed in a similar way to other types of louvres; just like other types of louvre, their specific placement will depend on the design of your HVAC system. However, the key difference between normal louvres and Sand Trap Louvres is that Sand Trap Louvres, in addition to the mitigation of rain ingress of normal louvres, also remove larger airborne particulates from the air. This makes them appropriate for areas where there is large amounts of airborne sand or dust which could be into ventilation systems. This makes them suitable for desert areas of the world such as the Arabian gulf, but is equally valid near quarries or beaches closer to home. Why Are Sand Trap Louvres Necessary? In these areas, the specification of sand trap louvres should be considered over standard louvres. They will function as a pre-filter, preventing larger airborne particles from being drawn into the system. This will not only reduce the possibility of damage to dampers, fans etc., but also extend the life of filters, maintaining system efficiency for longer and reducing costs associated with cleaning and replacement. How Do Sand Trap Louvres Work Sand Trap Louvres work via a simple system of interlocking louvre blades. These catch up to 92.5% of dust and sand. This material falls onto a sloped cill, where it is then expelled from the louvre by gravity. Our Series STL sand trap louvre has been independently tested by BSRIA against EN 13181:2001, the test results are detailed in our product brochure and the full report can be sent on request. Depending on your needs, this type of Louvre can be further modified with a rear-mounted volume control damper installed, in order to control the amount of air that passes through the louvre. As well as this, there are a range of powder coating options available. Get in Touch With HVC Today For over fifty years, HVC have been providing our customers with high-quality HVAC components, including fire dampers, volume control dampers, and louvre doors of various sizes. Our products have all been designed with customer safety in mindm. For information on our range of Sand Trap Louvres, or any of our other products, get in touch with HVC today. Our experienced and dedicated team will be happy to answer any questions you may have.