A condensing unit is a device that is used to condense a gaseous substance back into its liquid form through cooling. A condenser unit technically is a type of heat exchanger, and its size varies from an extremely small device all the way to large, industrial-size units. Condensing units also are incredibly varied in application, with uses such as cooling in refrigerators, air conditioners, chemical reactions and especially steam turbine power plants. Water typically is used as a coolant in the condensing process, but other forms of coolants also have been employed successfully.

A surface condenser is a type of condensing unit often found in steam power plants. A typical steam cycle consists of water being preheated and brought to its boiling point, at which time it is vaporized, or superheated, into high-pressure steam. This steam is delivered to a series of turbines, where after going through multiple cycles, is condensed back into water. The condensing process is an extremely important part of the steam cycle, because it allows for a steam plant to recycle steam that otherwise would have been wasted. For this reason, condensers help increase efficiency in steam power plants by reducing water demands.

Typically, surface condensers consist of a shell and tube construction. This is where cold water runs through a series of tubes within a metal shell filled with exhausted steam. The cool water brings the pipes to a relatively low temperature, which then cools the steam within the shell. After the steam is condensed, water is collected below the unit in a hot well. On smaller steam applications, the condensing unit can take a form similar to a car radiator.

Condensing units also are commonly used in chemical applications. A laboratory condensing unit, however, is far different from what one would see in a steam power plant or an air conditioner. Unlike common heat exchangers, laboratory and chemical condensers consist of a large glass tube through which water flows. In the middle of this larger tube is another smaller tube, into which a hot vapor enters. Upon entry, the cooling effect of the water surrounding it brings the vapor to a temperature at which it can condense.

Heating ventilation and air conditioning (HVAC) is a contemporary concept designed to regulate the temperature and quality of the air as well as level of humidity in commercial and residential buildings. The practical face of this technology is the HVAC pump, which performs the heating, cooling and dehumidifying functions through its two main components: the external condenser and an internal evaporator coil. Installing multiple systems in a single unit makes it a cost effective and efficient choice as compared to the traditional heating and cooling options. Apart from resulting in a significant reduction in consumer electricity bills, it also helps customize the climate within the room through insulation and constant filtering.

One of the first aspects governing the purchase of an HVAC pump is a close scrutiny of the equipment, which comes in a variety of dimensions. The size of the HVAC equipment generally determines its capacity; while a unit meant for home use would be typically small, one being purchased for industrial requirements would be much larger and bulkier.

HVAC systems can generally be categorized into four different types based on their method of operation and the design of the space in which they will be installed. An HVAC pump can be a furnace and condensing system, a heat pump and fan coil system, a zoning system, or a combination of each. Another innovation within the field is the introduction of more sophisticated HVAC system that has the added advantage of being eco-friendly as well.

For an HVAC pump to keep the occupants of a room cool in summer and warm in winter, preventative maintenance in the form of regular checks by a certified expert is a must. A routine inspection includes a complete examination of the unit, an estimate of the extent of wear and tear, cleaning the air filter, and replacing parts as required. In case of a sudden breakdown, assistance should be sought only from qualified professionals in the field. It is imperative for an HVAC owner to realize that because HVAC repair is a specialized industry, many repairmen are not licensed to diagnose or service an HVAC pump.

A ductless air conditioner is an air conditioning system that allows homeowners to enjoy the benefits of cooled air without the high cost of duct work. They are an affordable alternative to central heating, ventilating, and air conditioning (HVAC) systems, which rely on an extensive network of ducts to move air. Ductless air conditioners are considered to be more efficient and easier to maintain than window-mounted units.

Wall Split Air Conditioner. One Time Installation.

There are many advantages to using a ductless air conditioner instead of a traditional window-mounted unit. First, because the noisy compressor sits outside, the air conditioning system is much quieter inside the home. The fan itself is generally no louder than a regular ceiling fan, though “quiet fans” are available for homes where noise is a special concern. There is also no need to remove and re-install these units every summer, and homeowners are not subject to the security risk associated with removable window-mounted air conditioners.

There are many advantages to using a ductless air conditioner instead of a traditional window-mounted unit. First, because the noisy compressor sits outside, the air conditioning system is much quieter inside the home. The fan itself is generally no louder than a regular ceiling fan, though “quiet fans” are available for homes where noise is a special concern. There is also no need to remove and re-install these units every summer, and homeowners are not subject to the security risk associated with removable window-mounted air conditioners.

Residential uses for duct pipe include heating, ventilation, and air conditioning (HVAC), dryer exhaust vents, vents for cooking range hoods and gas fireplaces, and more. Typically, residential HVAC duct pipe is a flexible, insulated duct moving air from an air conditioning unit to rigid metal register boots faced with an adjustable vent plate that regulates air flow into a room. In residences where a furnace is used for heat, the duct pipe is typically rigid metal from furnace to room register or vent plate.

Other residential applications require duct work of different sizes and materials from HVAC, which might be 16 inches (about 41 cm) in diameter or larger. Dryer duct pipe connecting a dryer to a rigid vent might be a length of 4-inch (about 10 cm) diameter plastic tubing. Rigid metal ducting is often used to vent cooking range hoods and gas fireplaces to the outdoors, while a residential workshop may use flexible plastic pipe for sawdust collection. Where very hot gas produced by a gas fireplace or furnace passes through a ceiling, a multi-chambered, insulated section of pipe is installed to prevent fire.

In residential air ducts, fans are often installed to propel air from one place to another. In HVAC applications, a fan moves air into the house, while exhaust fans move undesirable or dangerous fumes from the house to the outside. Bathroom fans remove moist air from the house to help prevent dampness and mold. Duct supplies for repair or remodeling projects are readily available at building supply or hardware stores.

 

In industrial applications, more specialized duct work is often required. CPVC is often employed when liquid at very high temperature is moved, and polyvinyl chloride (PVC) might be used as a duct pipe for hazardous or corrosive liquid. These products are available in a wide range of sizes and are economical and comparatively easy to install.

HVAC diffusers are outlet vent points on heating, ventilation and air conditioning (HVAC) systems. Although they are occasionally used as return air vents, their main purpose is to introduce conditioned air into a space in such a way that even distribution and mixing is achieved with minimum noise. HVAC diffusers are produced in a variety of standardized sizes and are generally square, rectangular or round; they typically feature sets of louvers or fins that direct air flow in a preset pattern. Larger, industrial diffusers may include adjustable louvers or dampers, which can be manually or automatically adjusted to control airflow volumes. Although diffusers are often seen as no more than decorative grills for inlet vents, they play an essential role in the efficacy of HVAC systems and should be correctly matched to any given application.

The conditioned air produced by HVAC systems requires correct introduction into any space for it to realize its full potential. Haphazard conditioned air inflow into a room can cause localized hot and cold spots and completely rob the area of much of the benefit of heating and ventilation. Uncontrolled inflow of air can also be annoyingly noisy. HVAC diffusers reduce the velocity of the incoming airflow and direct it to ensure effective mixing and maximum benefit with minimum noise.

Most HVAC diffusers used in domestic and light commercial applications are no more than clip- or screw-on grills made of light-gauge metal, plastic or wood that cover inlet vents. The diffuser has a number of louvers or grill fins arranged in a specific pattern, superimposed over the vent opening. These louvers or fins offer a directional obstacle to the incoming air, reducing its velocity and forcing it in a specific direction. Diffuser grills may be linear in design and direct the air upward or to the side, or they may have radial fins that distribute the air evenly in a 360° pattern or a preset arc. These patterns of directional air flow have to be matched to the specific space to ensure adequate mixing of conditioned air.

Heavy industrial diffusers are similar in design but may include adjustable dampers. These devices can be turned manually or remotely operated via a solenoid driven by a central control system. These adjustable dampers can direct air flow in a specific direction, control the volume of the airflow or produce a combination of both functions. These HVAC diffusers are generally constructed of aluminum or steel and are larger and more utilitarian by design than domestic varieties.

One of the most frequent concerns with heating, ventilation, and air conditioning (HVAC) systems is how to balance energy efficiency with proper ventilation. As the focus on green building has increased over the years, builders have responded by constructing homes more tightly. Tighter homes allow less air to leak through exterior walls, resulting in improved energy efficiency.

 

As housing construction has gotten tighter, however, there have been fewer natural paths left in the buildings to allow fresh air to enter the home. This lack of fresh air can result in poor indoor air quality, along with mold growth and other moisture-related problems. Poor ventilation can also make a building feel stuffy, and may lead to unpleasant odors inside the home.

To enjoy the benefits of both conditioned air and adequate ventilation, homeowners can use a heat recovery ventilation system. This device is used in conjunction with the HVAC system to remove valuable heat from exhaust air before it exits the home. The heat recovery ventilation system collects this heat, then distributes it into fresh air as it enters the home. This means that less heat is wasted, and energy efficiency levels are improved.

A heat recovery ventilation system can be installed in the basement or on the rooftop to work alongside existing HVAC equipment. It is connected to the supply and return ducts in the home, which enter the heat recovery unit through separate pathways. One fan in the recovery unit draws stale air in from the home. Another fan within the unit draws in fresh air from outside. As the exhaust air passes through the core of the unit, heat is collected inside of this core before the air is exhausted to outside.

 

As the heat recovery ventilation system draws fresh air in, the air passes through the core of the unit. As it passes, it collects the heat left behind from the exhaust air. The heat is then transferred to the supply air and distributed through the home.

A humidistat is a mechanism that works in conjunction with space conditioning machines to regulate a room's humidity level. They are commonly used with air conditioners, humidifiers, and dehumidifiers, gauging the humidity in a given space. When used on a device with a thermostat, such as an air conditioner, a humidistat allows the unit to turn on and off when a predetermined level of humidity is present.

Mitsubishi Ductless Split System Air Conditioner. Typical Range Programmable.

A digital humidistat is easy to read and adjust. It displays the temperature of the room, the level of humidity, and often will show the target temperature and level. Most models are simple to program with the preferred information, and many also include security settings that guarantee the unit runs properly even if the humidistat is tampered with.

 

Since humidity levels vary in different geographic areas, it is important to consult the humidistat manufacturer's guidelines to establish the optimal setting for a given locale. If the device is set improperly, it could cycle on when it is not needed, wasting energy and escalating utility costs. Most manufacturers include with each product a listing of ideal humidistat settings for a wide variety of locations.

To become a heating technician, you often will need to attend a formal trade school or complete a technical training program. An alternative way to become a heating technician is to seek out a company that offers on-the-job training through a full apprenticeship by working directly with a licensed heating, ventilation and air conditioning (HVAC) installer. You also will need to understand a lot of technical information to become a heating technician, including having the ability to read blueprints, a working knowledge of the physical properties of electricity, the ability to understand physics and the capability to learn the various heating systems, including forced-air, boilers, oil burners and geothermal heating systems.

HVAC schools range from six to 24 months of training, and they teach you how to diagnose heating and electrical problems, how to use the various tools and meters that are used during the repair, maintenance and installation of HVAC systems. After you have completed the full program, you will take an HVAC certification exam, which covers all areas of installation, maintenance and repair. Passing the certification exam will allow you to work for a company or start your own business. An apprenticeship-type job can last from three to five years, and it allows hands-on training to become a heating technician. As an apprentice, you must be able to demonstrate your knowledge of mechanical work prior to being able to practice on your own.

Deciding to specialize in the installation and maintenance of heating systems is a big decision and covers a lot of areas of expertise. Two fairly distinct areas of expertise are residential and commercial heating and air contracting. Computer skills are an asset, because HVAC software programs can help calculate and determine the equipment size and load needed for specific building requirements.

The HVAC field is a growing and ever-changing field as more and more companies look for ways to install cost-effective, high efficiency heating and cooling equipment. Also, environmentally friendly systems are being installed as governments provide various rebates to upgrade HVAC systems. Another area of expertise for a heating technician is to specialize in the healthcare industry. Hospitals require allergen and dust-filtering systems to maintain adequate clean air for the main hospital, intensive care units and operating rooms.

Cooling systems like fans, air conditioners, heat pumps and whole house fans are the primary methods of recirculating air, and they are implemented to make life more comfortable indoors. Each of these air circulation methods depend on moving parts to force the air to be expelled quickly throughout living quarters. During the hot summer months, it is the steadily moving air currents which provide relief from incessant sweating and dehydration, the two main forms of bodily discomfort. The added benefit of recirculating air also improves the atmosphere within the room through filtering the moving air, which helps trap allergens and particles.

The purchase of an air circulation system depends on three main factors: price, energy consumption and effectiveness. Normally, a perfect system would be the one which is highly efficient in terms of recirculating air and energy consumption while being available at a reasonable price. Humidity also comes into play in many areas of the world, and in some cases, even the most powerful air conditioning units struggle with recirculating air. A more thorough solution would be combine this technology with ceiling fans, window fans and whole-house fans to increase the recirculating air throughout the environment, which actually makes the main unit more efficient.

Air conditioning is a contemporary option which not only ensures cooler temperatures, but also creates a healthy and germ-free environment. Depending on its installation, an air cooling system might be either centrally located or wall mounted. While the former is effective throughout the house, the latter is suitable for cooling down a single room or small area only. In hot and humid countries, an air conditioner is no longer considered a luxury, but a common possession. The growing demand has caused the industry to greatly expand, with future projections centered on finding more energy-efficient models that use safe coolants.

Another method of recirculating air is to employ heat pumps; these types of models feature both the heating as well as the cooling systems within the same unit. In summer, the heat pump functions like an air conditioning unit that can considerably reduce the temperature and humidity within a structure, and it can also deliver heating in the winter months. Since the air from outside is continuously pumped into the dwelling, recirculated air is frequently being replaced, and the overall indoor air quality improves.

A digital thermostat can control the heater and air conditioning (AC) unit in a building, replacing standard analog heater thermostats present in older homes. Among the advantages of switching out the old unit for a new digital model are convenience and savings in the form of a lower energy bill.

 

Standard thermostats are commonly mounted on a wall in a convenient location where they monitor the room’s air temperature. They are set by adjusting a pointer over a specific temperature along a dial. The thermostat will only trigger the heater on if the temperature in the room falls below the setting. Once the heater comes on, it will stay on until the room warms back up to the setting. At that point, the thermostat turns the heater off.

 

The problem is that analog thermostats are typically set to a comfortable temperature and left there. As a result much energy is wasted heating the home during the day when no one is there, or at night when everyone is asleep. A digital thermostat is programmable, allowing you to choose which hours you require heating (or air-conditioning), thereby saving energy and money.

There are several brands and models available, with the most basic unit allowing one user-configurable program to run Monday through Friday, and another on weekends. A user might choose to have the heater kick on at 6am during the week, turn off at 9am while the house is empty, turn back on at 3pm just before the kids get home, then shut off again at 11pm for bed. For weekends, the thermostat can be set to a different routine.

 

This model can be sufficient for people who keep a uniform schedule during the week and on weekends. More advanced models allow each day of the week to be programmed individually for added flexibility, including Saturday and Sunday.

Once the digital thermostat is programmed, you never have to think about it again. It will heat or cool the house according to your schedule without the hassle of manually turning it on and off. It’s also easy to temporarily override a program without having to reprogram it. Simply tap the “up” or “down” keys on the face of the unit to temporarily adjust the temperature setting up or down. Some units will hold this temporary setting for a period of time before resorting back to the program, while others have a reset key you can tap to return to standard programming.

It’s quite easy to replace an analog thermostat with a new digital model. The old unit is typically held to its mount by one or two screws. Before uninstalling it, switch off power to the unit at the main circuit breaker panel. After removing the screws, wiring coming through the wall to the unit will need to be disconnected and reconnected to the new digital thermostat. The number of wires will vary depending on attached equipment. Be sure to follow all instructions carefully, connecting the correct leads to the correct posts, including the ground wire.

 

Virtually all digital thermostats come with the ability to control a heater and AC unit both, but if you don't have AC it isn't a problem. Units with fewer programming options cost less, but an advanced model might run $50 US Dollars. An advantage to paying a little more for a digital thermostat is that these models are usually easy to program while the least expensive units might not be as user friendly.