Ongoing
economic and indoor environmental concerns require HVAC innovation. New liquid desiccant air conditioning systems offer
substantial energy savings and greatly improved humidity control in
applications where latent loads (moisture) are very high relative to sensible
loads.
Moisture in building envelopes can have serious consequences. For example, moisture in insulation reduces its insulating capability, causing heating and/or cooling losses and wasting energy. Moisture can also cause structural deterioration and foster mold growth. Thermal imaging is well suited to identifying wet spots.
Smart HVAC equipment that recognizes when it is failing or has failed, or when conditions have drifted outside its optimum range, could save substantial amounts of energy if the equipment sent useful information to the building owner or contractor. This is referred to as automated fault detection and diagnostics (FDD).
While synchronous drives do have many industrial applications, they are generally not accepted as the best option for HVAC equipment. Virtually no OEM uses or recommends synchronous drives due to cost, noise and vibration, structural design concerns, and reliable availability of replacement components.
Energy recovery ventilation (ERV) systems exchange heat (often both sensible heat and water vapor) between the outgoing exhaust air and the ventilation air being brought in. Under appropriate conditions, this allows reducing the capacity of the HVAC system and saves energy.
Conventional wisdom would have you concentrate thermal imaging on windows and doors. However, windows and doors contribute very little to total air leakage in most dwellings. In fact, the most serious leaks occur at the top and bottom of the conditioned building envelope - in attics and basements.
Advanced packaged rooftop units (RTUs) are emerging with higher efficiencies and additional features designed to save energy off-peak and improve reliability. Features include improved fans and economizers; better controls for the fan, refrigerant cycle, and economizer; and advanced monitoring and diagnostics.
V-belt drive misalignment exists when the driver and driven sheaves are not properly aligned. Misalignment can take either the form of angular or parallel (offset) misalignment, or a combination of both. Ideally, you want to have both parallel and angular harmony.
Chilled beam systems provide savings by replacing fan energy with pump energy. They use pumped chilled water instead of blowing cold air. Water has much higher heat capacity, both by mass and volume. In typical pump and fan arrangements, this has been shown to translate into a reduction in fan energy by a factor of seven.
This article, reprinted from an EXHAUSTO white paper, discusses the benefits of demand-controlled ventilation (DCV) systems in multi-story, multi-residential buildings, which include improving building energy efficiency, enhancing comfort and other key performance factors. It reviews the application of DCV in new, retrofit and renovated building projects.