HVAC heating and Air Conditioning

The HVAC system uses three closely related functions, namely, heating, ventilation, and air-conditioning. These functions are uniquely set up so that they can regulate temperature and humidity in residential homes, public offices, and other building facilities with respect to the overall design of the structures.

Heating

Most modern structures in colder regions in the world and in countries with temperate climate such as the United Kingdom usually install a heating system. This mechanism is used to regulate temperature in residential homes, public offices, and other dwellings.

The heating system can either be central or local. The most commonly used setup is the central heating system where the heating is concentrated in one area—central—and is then circulated for various heating processes and applications.  Heat values of fuels are based on BTU to cubic foot measurement for HVAC.

In the central heating system, there are three common components used. A furnace is an enclosure used for heating and can be found at the basement or at the attic. Different cultures have various interpretations of “furnace.” For the Americans, it is similar to kiln while for the British, it is equivalent to industrial furnaces.

Whatever it may be, it still uses the same principle for heat distribution—that is, it transfers heat using an intermediary distribution system. A boiler, meanwhile, is a type of furnace—in fact, a closed vessel—that distributes heat through steam.

Thermodynamic principles are the bases for a heat pump. This device causes the temperature to rise through heat transfer. A heat pump is very effective especially for very cold air since it has the ability to heat it at the shortest period. An efficient heat pump uses lesser energy and thus power.

A radiator is a heating device that circulates steam or hot water through pipes found inside an upright metal structure. This term is also commonly applied to some types of heat exchangers. It is a common perception among people that heat is transferred from a heat exchanger through radiation when, in fact, it is not. It transfers heat by convection, which uses currents.

Please note, though, that the central heating system is completely different from your hot water supply. For instance, the water used in the former is not the same as your tap water.

Ways of Central Heating

There are a number of methods for central heating. In electric heating, an electrical heater is used. It is a device that transforms electrical energy into heat.

Every electric heater contains an electric resistor, which acts as its heating element. Right now, there are many variations of electrical heaters that deliver different amounts of heat, but all of them use the same principle: Joule heating.

An electric current that converts electricity to heat is allowed to pass through the resistor. In hydronic heating, heat produced is commonly transferred to fins found along pipes in baseboard HVAC registers. You can also use coal, propane or natural gas, pressurized oil, or earth, which is used as a heat pump.

Air-conditioning

Over the years, air-conditioning has changed home lifestyle. A lot of London homes right now take advantage of wall-mounted air-conditioning systems. They are often placed in the living room, bedroom, kitchen—in almost all over the house.

Most buildings and offices also have hidden condensing units. Cooled places become refuge to those who are tired with the rising temperature outside.

There are various air-conditioning systems in the market, but they all function just the same. They control temperature, ventilation, and humidity in an enclosed environment. Hilsch air-conditioning uses a vortex tube called Ranque-Hilsch vortex tube for cheap spot cooling when you there is compressed air. However, it is not as efficient as usual air-conditioning equipment.

It is advisable that homes, buildings, and other offices have sealed windows to maintain the quality of air produced by the system. Furthermore, it is better to check the dwelling first to make sure that air conditioners can really be installed since they often use large ducts.

But you really don’t have to worry too much if it isn’t. You can still take advantage of remote coils or use the split system. Yet it is always preferable to maintain the cleanliness of the ducts to prevent the growth of pathogens that can definitely cause illness. Sometimes chemical monitoring of HVAC systems is needed to always ensure indoor air quality.

Seawater Air-conditioning

Ever heard of seawater air-conditioning? The seventies brought an energy crisis that drove scientists, engineers, and other concerned individuals to focus their minds on a much-cheaper energy source alternative.

Thus, they considered developing an air-conditioning system using seawater.

Initial studies, however, encountered a lot of problems. First of all, the cost for SWACS (seawater air-conditioning system) was not yet properly determined because the appropriate pipelines needed were not yet built.

To make matters worse, there were still a lot of unknowns with regard to the heat exchangers. Through continuous studies, OTEC (Ocean Thermal Energy Conversion) was able to develop more useful and reliable types of pipelines and heat exchangers.

Fundamentals of SWACS

Cold seawater can be taken from the bottom of the ocean or from the lakes. Other specific places like Hawaii and Fort Lauderdale and Miami in Florida are also favorable spots.

SWACS makes use of the following main components: a heat exchanger, freshwater distribution system, and seawater supply system. For maximum efficiency, you can adjust these three factors to suit the climate, location, and type of facility this system is installed.

Cold water is pumped deep either from the ocean or from the lake. It then passes through a heat exchanger, which is usually contained in a cooling station.

It is now the heat exchanger’s job to transfer heat from the freshwater distribution loop to produce cold water, which will be later distributed all throughout the building for air-conditioning.

Sometimes it is economical and practical to use auxiliary chillers. To supply deep cold seawater to maintain minimum temperature is, more often than not, impossible or remote.

First, seawater cools the chilled freshwater using a heat exchanger; then an auxiliary chiller is used to secondarily cool it.

As long as the coolness of the condenser is maintained, it can work efficiently.

Benefits of Seawater Air-conditioning

SWACS functions similarly to a conventional air-conditioning system. However, if it comes to economic savings and environmental friendliness, SWACS is a better choice.

SWACS can help you save approximately 90 percent of energy used. In most companies, air-conditioning cost is quite huge, approximately two-thirds of which is for chillers’ and cooling towers’ operations. SWACS’s chillers last longer than that of a conventional air-conditioning system. Moreover, it hardly depends on any future price changes of energy. But it should be noted that though this system has low operating cost, it has a high capital cost.

The use of SWACS also minimizes pollution and greenhouse effect.  This system doesn’t depend on fossil fuels, reducing air pollution and acid rain. It also prevents greenhouse effect since it uses a simple heat exchanger instead of a CFC-producing chiller machinery. CFCs (chlorofluorocarbons) cause the continuous depletion of our ozone layer.

Viability of SWACS

Site location is one of the major factors that determine the overall viability of SWACS. Others are the following:
·    Air-conditioning load size
·    Utilization of the air-conditioning system
·    Electrical costs
·    Onshore distribution system
·    Distance offshore to cold water

SWACS is one of the most vital energy source alternatives because of its economic and environmental benefits.

Though the system is not altogether perfect, it has potential in helping us curb the continuing rise of energy prices. What’s more, we can keep our own planet Earth clean, free, and safe for all of us to live in.