The HVAC industry is booming. People are becoming increasingly concerned about indoor air quality and want to know more about the systems that regulate it.
HVAC is an umbrella term for heating, ventilation and air conditioning. It includes products like furnaces, air conditioners and heat pumps as well as ductwork and thermostats. Contact Ausco Air Heating & Air Conditioning for professional help.
HVAC systems perform heating, ventilation and air conditioning functions in residential or commercial buildings. They help maintain high indoor air quality by providing fresh outdoor air to dilute airborne odors from occupants, volatile organic compounds emitted by interior furnishings, chemicals used for cleaning and other contaminants. HVAC systems also provide thermal comfort.
Most conventional HVAC setups use a gas furnace or boiler in conjunction with an air conditioner, although heat pumps are increasingly common because they can be used to both heat and cool a building. The heart of an HVAC system is its thermostat, which signals the system to turn on and off based on its temperature settings. Thermostats are available in manual, programmable and smart models, the latter offering the most convenience and efficiency.
The evaporator coil in an air conditioner contains refrigerant which absorbs and holds heat from the air. A blower fan pushes air through the evaporator coil and into a ductwork network, where it is distributed to individual rooms via vents or registers. The blower fan may be driven by electricity or a combustion engine, depending on the type of system being used.
In older HVAC systems, the thermostat senses low temperatures by detecting a change in resistance between its two exposed contacts. When the thermistor senses that the temperature has dropped, it bends a bimetallic strip element, breaking the first contact and closing the second. The system activates and begins to warm the home or office. Modern thermostats have coiled bimetallic strips sealed behind glass to prevent dirt from interfering with their operation.
Cooling
A major part of HVAC’s role is to help keep spaces cool, which is a necessity during warmer months. Air conditioners provide cooling by drawing in and circulating air through an internal evaporator coil that absorbs heat from the indoor air before discharging it outside. The evaporator coil also helps to lower the humidity levels in a space.
The evaporator coil and other components are powered by the refrigerant, which is typically a chlorine-free hydrochlorofluorocarbon (HCFC), or more recently, a non-CFC alternative known as R-410A. HCFC’s pose environmental risks and are gradually being phased out by manufacturers in favor of more eco-friendly options. It’s recommended that homeowners replace their HVAC air filters every 2-3 months or according to the manufacturer’s guidelines to ensure optimal airflow and performance.
Ventilation is another vital component of HVAC, and it works to promote thermal comfort by regulating indoor air quality. This includes removing moisture, smoke, odors, dust particles, airborne bacteria and carbon dioxide from the indoor air, as well as circulating fresh air throughout a building for oxygen replenishment.
HVAC ventilation systems often consist of ductwork, a blower system and a filter. Ductwork delivers conditioned air from an outdoor unit to the interior of a home or building, while a filter keeps unwanted particles and allergens out of the indoor air.
The blower is responsible for circulating air through the ducts, and it is driven by an electric motor. The motor is controlled by a thermostat, which is set to the desired temperature of the room or building. Most modern HVAC systems include a programmable or smart thermostat to offer greater flexibility and convenience for the homeowner.
The field of HVAC is broad and encompasses all aspects of indoor climate control in residential, commercial and industrial applications. Some common HVAC components include furnaces, air conditioners, heat pumps and ductwork, along with thermostats and other home comfort controls. Keeping these systems in good working order is crucial to ensuring optimal occupant comfort, health and productivity. Contact Petro Home Services for expert HVAC installation, maintenance and repair services.
Ventilation
Ventilation involves pulling air into the HVAC system, heating or cooling it and then pushing the conditioned air through ductwork throughout the home. A ventilation system helps to control humidity, reduce odors and eliminate harmful bacteria and other airborne pollutants. Without a proper ventilation system, these contaminants can build up and cause allergies and other health problems in school occupants.
Ventilators are an essential component of any HVAC system, and there are several different types to choose from. For example, heat recovery ventilators (HRV) and energy recovery ventilators (ERV) are designed to improve indoor air quality by circulating fresh outdoor air while reducing energy consumption. These systems also provide pre-conditioned incoming air, thereby increasing comfort and energy efficiency.
In addition, there are standalone ventilation units that are designed to improve indoor air quality by removing harmful contaminants and increasing oxygen levels in the air. These units include air cleaners or air purifiers, dehumidifiers and filtration systems.
The basic components of a ventilation system are an air handler, return vents and the blower assembly. An air handler contains a coil of refrigerant that converts liquid to vapor by absorbing heat from the indoor air that is blown across it. The vaporized refrigerant is then used to cool the indoor air, which is circulated by the blower assembly through the duct system.
Various methods can be used to evaluate ventilation effectiveness, including tracer gas testing and computational fluid dynamics. These techniques can help to determine airflow velocity, direction and the size of ducts. Another method that can be used to estimate the energy efficiency of a ventilation system is a heat loss analysis.
Regardless of the ventilation system that is chosen, it is important that the design team makes sure that the system is properly sized and installed in order to maximize comfort and energy efficiency. Additionally, it is important that the system is easy to maintain. This means that the air handling unit, controls and exhaust fans should be easily accessible and not require ladders, removal of ceiling tiles or crawling to reach.
Air Filtration
Air filters are one of the most important elements of a home HVAC system. They filter out bacteria, fungus spores and allergens from the recirculated air in your house, which can help reduce the risk of respiratory infections, dermatitis and allergies. Unlike electrostatic precipitators or ozone generators, which only remove volatile organic compounds and some bacterial and fungal particles, air filters are designed to capture larger-size biological particulates as well.
There are several types of air filters available for your heating and cooling system. A standard fiberglass filter, for example, is disposable and captures pollutants in layers of fiberglass materials that are electrostatically charged to attract contaminates. This is an inexpensive solution that may be suitable for homes with limited budgets. Pleated filters are a more efficient alternative that can be used in many residential applications. These filters have an accordion-like filtration media pile, which makes them more effective than standard fiberglass filters. These filters are more expensive than standard fiberglass filters, and they need to be replaced every two or three months.
More sophisticated filters, such as HEPA (high-efficiency particulate air) filters, are also available for use in the home. These high-efficiency filters are able to trap very small microbes, including bacteria and fungus spores. In addition to HEPA filters, there are now filter systems that incorporate antimicrobial agents or chemical coatings that kill the bacteria and fungus on contact.
It is important to note that standard HVAC systems do not typically operate properly with filters with MERV ratings higher than 16. Filters with a MERV rating higher than 16 are thick and dense, and they restrict airflow through the furnace system, which can cause equipment damage.
It is also important to note that the MERV system rates a filter’s ability to trap solid particles, but does not account for the removal of volatile household gasses such as ammonia or carbon monoxide. As a result, it is recommended that you install a stand-alone air purification appliance in addition to an HVAC filter, if you have serious concerns about indoor air quality.
