Mechanical and electrical construction

DR

1. What is the difference between air conditioning and refrigeration?

The difference between these two is that air conditioning is the process of cooling the air in a building to provide a comfortable temperature and refrigeration is the process of moving heat from an area where it is undesirable to an area where the heat is not objectionable.

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2. How does an AC unit work?

An AC unit works by drawing out the warm air inside and removing its heat. First the compressor condenses and circulates the refrigerant through the unit changing the gas to a liquid. The liquid then goes through the cooling compartment. Fans circulate on the inside and let air pass across the evaporator fins. The evaporator's fan exchange thermal energy and air around it and there the refrigerant turns liquid into vapor removing heat and therefore, the air is cooled ans blown back into the house.

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SP

3) What are the advantages of a steam heating system?

Hydronic systems also known as chilled water 4 pipe or 2 pipe systems use water as the means of acting as the refrigerant in a system.

Steam heating systems carry hot gas or steam from the point of generation to the point of use in any building or space.  Steam heating advantages is that it can provide more BTU per pound of steam than water.  This type of system does not require external mechanical pumping like a hydronic cooling system does.  As long as there is a pressure differential, steam will flow to the longest point without the use of any additional mechanical pumping.  You also get a better heater transfer surface area with steam vs water.

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4) Why do hydronic systems work so well?

A hydronic system can be used for both heating and cooling for very large occupancy spaces for human comfort.

Hydronic system also known as chilled water 2 or 4 pipe loop systems uses "water" as the refrigerant medium to absorb and reject heat from the space to be air-conditioned or cooled.  A hydronic system uses a chiller system that cools water which then cools the air for the entire system.  The water acts as the heat transfer medium for both heating and cooling. Energy wise, the hydronic system can provide a lower and more efficient KW/ton.

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DR

1. What is the difference between air conditioning and refrigeration?

The difference between these two is that air conditioning is the process of cooling the air in a building to provide a comfortable temperature and refrigeration is the process of moving heat from an area where it is undesirable to an area where the heat is not objectionable.

Respond to DR:

2. How does an AC unit work?

An AC unit works by drawing out the warm air inside and removing its heat. First the compressor condenses and circulates the refrigerant through the unit changing the gas to a liquid. The liquid then goes through the cooling compartment. Fans circulate on the inside and let air pass across the evaporator fins. The evaporator's fan exchange thermal energy and air around it and there the refrigerant turns liquid into vapor removing heat and therefore, the air is cooled ans blown back into the house.

Respond to DR :

BH

3. What are the advantages of a steam heating system?

More Btu/lb than water, allowing steam to be used in a limited space, steam does not need to be pumped to the location of use, centralized location of the boiler, steam flows up through the pipes which allows the condensate to fall back down into the boiler to be used again.

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4. Why do hydronic systems work so well?

Because they use a boiler to heat the water to create steam to heat up buildings or warm the water used to heat up buildings. The water leaves the boiler at 200F and returns at 140F. The boiler is centralized making for smooth (hopefully) repairs. All accessories are designed specifically for the operation of the boiler and the other systems. Hot water or steam is distributed through a system of pipes that also work to retain/maintain the heat of the steam or water. 

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VV

1. What is the difference between air conditioning and refrigeration?

The main difference between an A/C and a refrigeration system is that a refrigeration system is the process of moving heat from an undesirable area to an area where it is not objectionable while an air conditioning system is the process of cooling air in a building to provide a comfortable temperature. A refrigeration system controls pressure and temperature of a refrigerant to regulate absorption and rejection of heat by refrigerant. An air conditioning system distributes cool air to building spaces by removing heat from air or water to then exhaust heat where it is not desirable.

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