This is the place to rant, rave, brag, belly-ache, crack a joke, procrastinate, and delve into the metaphysical aspects of the DIY mindset. We’re off the map, on a tangent, and frequently off topic. This is the stuff we don’t show on TV.
Fire dampers are dampers which are forced to close in the event of a fire. There are different kinds of fire dampers, and they are classified according to the following factors: how they are actuated or forced to close; the physical constraints of their installation; and the fire rating of the ceiling, floor, or wall being penetrated.
A variable-air-volume unit, or VAV box, as they are commonly called, is part of an air conditioning system. It is a device installed in the supply ductwork which regulates the volume of air being delivered to a zone. A zone is a defined space that is governed by a single thermostat or sensor, and for which there is a main supply duct that subdivides into as many ducts as are required to fully air condition the zone’s spaces. The device itself regulates the air passing through it by opening and closing a damper, and it can vary the quantity of air which passes through it. As the thermostat senses the need for more air conditioning, it signals the VAV to open the damper, and vice versa.
Particulates, which can include mold and spores, are implicated in many human illnesses. Particulate air filtration is simply the removal of intruding particles from the conditioned air steam.
A furnace is an enclosure through which air is either drawn or pushed, and it contains, at minimum, a method for filtering and heating the air. A furnace may also have a method of cooling the air (or removing heat from the air, thus leaving it cooler). Furnaces are commonly used heating and cooling devices.
Central HVAC equipment falls into many categories, including thermal storage and air-to-air energy recovery equipment. Following is a list of equipment broken down by Master Format heading.
A fan-coil unit is simply an enclosure consisting of a fan and at least one coil. These units are available with chilled water coils and they may have hot water, steam and electric heating coils for added flexibility. The unit may be designed to be concealed or visible. In either case, the units have durable, heavy gauge steel construction.
Radiant heat refers to heat that emanates from a heated element or substance. Radiant heating systems do not rely on circulating heated air via ductwork or other means. Radiant heating units are manufactured assemblies designed to provide comfort heating through radiant heat transfer. Infrared rays are radiated from an electric or fuel-fired assembly until they are absorbed by objects -- floors, people, furniture, etc., which then transfer heat to the surrounding area.
This topic covers information related to testing, adjusting and balancing of heating, ventilation and air conditioning (HVAC) systems installed during construction. Testing evaluates HVAC equipment, adjusting sets devices within an HVAC system to achieve efficient performance during operation and balancing is performed to regulate air or water flow of an HVAC system.
This topic covers information related to dampers installed as part of HVAC systems during construction. Volume control dampers can be installed inside a duct or as part of a register or diffuser. They are adjustable devices that control the volume of air provided to a specific location within a structure. Smoke and fire dampers are installed inside a duct located in a firewall. They are automated devices that close to prevent the spread of fire.
This topic covers information related to flexible ducts installed as part of HVAC systems during construction. Flexible ducts are round in shape and can be made from plastic with glass wool insulation over metal coiled wire.
This topic covers information related to HVAC fans installed as part of HVAC systems during construction. HVAC fans can be one of several types; axial, centrifugal, power ventilators or air curtains. Axial fans in construction are commonly known as ceiling fans. Centrifugal fans are commonly found in mechanical units that distribute air. Power ventilators are used to draw air from a room or portion of a structure and remove heat and/or moisture, such as attic vents and gable vents. Air curtains are stand alone devices that generate a wall of air that separates two spaces, such as an entry from the outdoors to the indoors.
This topic covers information related to air terminal units installed as part of HVAC systems during construction. Air terminal units control or modify the amount and temperature of air being distributed to a specific zone in order to achieve a desired comfort level within the space. Air terminal units are either a constant or variable volume systems.
