Mystery Solved: Air Handler vs Furnace (Residential)

The video above, by Genteq Motors, gives a very good overview of how your average residential furnace works. For those of us, however, who has no life and would like to know more we will go into a little more detail in this article covering the history of heating homes to the difference between gas and electric.

Air Handler / Furnace
When you have electric heat it is called an air handler. When you have a gas heater it’s called a furnace. Up north you may have an oil burner, but that is also called a furnace. What they all have in common is a fan that circulates air in the house.

Want to learn more about Laponica Refrigeration? Visit us on our webpage by clicking on this photo. Link will open in a new tab.

Want to learn more about Laponica Refrigeration? Visit us on our webpage by clicking on this photo. Link will open in a new tab.

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What is meant by ‘ton’ of refrigerant?

Originating during the transition from stored natural ice to mechanical refrigeration, the term is used in many countries, particularly in North America, to describe the heat-extraction capacity of cooling equipment – whether it be refrigeration or air conditioning.

One ton of refrigerant refers to 12,000 B.T.U.s/hour (British Thermal Units per Hour) of cooling effect.

Example:                                                                                                                                A condensing unit with a cooling capacity of 60,000 B.T.U.s / hour has the capacity of 5 tons.

In, “What is HVAC and what does it mean?” we describe briefly that the cooling effect you feel from your air conditioner doesn’t come from the freon itself, but rather the effects of heat transfer.

References:                                                                                                                 Wikipedia contributors. “Ton of refrigeration.” Wikipedia, The Free Encyclopedia. 12Oct12. <http://en.wikipedia.org/wiki/Ton_of_refrigeration>.

What is SEER & EER?

Introduction

The Department of Energy (DOE) is directed by the Energy Policy and Conservation Act to establishing minimum efficiency standards for various consumer products; including central air conditioners and central air conditioning heat pumps. SEER and EER is a rating system created to measure the efficiency of an air conditioner or heat pump.

Both ratings should be considered in choosing cooling products. The rating is a ratio of the cooling output divided by the power consumption and measures the cooling performance of the system. The Federal government developed an ENERGY STAR program for high efficiency central air conditioning systems that in order to qualify must have a SEER of at least 14.

SEER rating

SEER stands for Seasonal Energy Efficiency Rating and is basically a number describing where an air conditioning unit falls on the efficiency scale, in regards to power consumption. It is calculated using the ratio of output cooling (Btu/hr) to input electrical power (watts).

Unlike EER, which is evaluated using a specific operating condition, SEER represents the overall expected performance of a unit, in a given location, for a typical year’s weather. It is measured using the same indoor temperature, but with an outdoor temperature range from 65 to 104 degrees fahrenheit.

The easiest way to think of a SEER number is by comparing it to how many miles per gallon a specific car is capable of handling. You might consider buying a Prius instead of a Hummer if gas prices is an issue. The same goes for a/c units – you would buy a unit with a higher SEER rating if you want a lower energy bill.

Concerning residential air conditioners, as of January 23rd 2006, new units sold in the United States by law must have a SEER rating equal to or greater than 13. Before 2006 the minimum standard was 10 (NOTE: A unit with a SEER rating of 13 is 30% more efficient than a unit with a SEER rating of only 10).

Homeowners are not required to upgrade to a higher efficiency model, but with an average lifespan of about 15 to 20 years low efficiency units (at least the ones below SEER 13) will eventually go away completely.

EER

EER is the abbreviation for Energy Efficiency Ratio and unlike SEER it does not take into consideration the time of year, but rather the system’s energy efficiency at a specific operating point. Just as SEER it is the ratio of output cooling (Btu/hr) to input electrical power (watts).

Recommendations by Laponica Refrigeration

While a consumers wallet is the number one deciding factor in purchasing a new unit there are some things a consumer should know about higher SEER ratings and the benefits of purchasing them.

If money is hard to come by Laponica Refrigeration recommends you at least try to purchase a SEER 16 unit. The savings you gain at that level will help pay for the extra cost in a minimal amount of time.

A unit with a SEER rating of higher than 16 may not necessarily provide the savings necessary to account for the extra cost, but they do tend to provide extra comfort accessories such as a variable fan speed on your indoor unit.

A variable fan speed keeps a more stable temperature in your house. In a standard air conditioner unit your indoor temperature will vary by approximately 3 degrees between cut-in and cut-out of the unit. Let’s say it is hot outside and you set your thermostat to 75 degrees. Your unit will cut off once it reaches 75 degrees. A normal unit will not turn back on before it reaches 78 degrees. This keep your house +/- 3 degrees from what you set it at. With a variable fan speed this does not happen and you end up with a more stable temperature inside your house.

 

References: 

United States of America. Department of Energy.ENERGY-EFFICIENT AIR CONDITIONERS: NEW STANDARDS COMING IN 2006 . Web. <http://www1.eere.energy.gov/buildings/appliance_standards/residential/pdfs/ac_factsheet.pdf>.

. “Seasonal energy efficiency ratio.” Wikipedia The Free Encyclopedia. Wikipedia, 13 2012. Web. 26 Nov 2012. <http://en.wikipedia.org/wiki/Seasonal_energy_efficiency_ratio>.

A/C Terminology

Introduction
For those of us who needs a little more help with the air conditioners jargon – Laponica has compiled a list and explanation of some of the most common terms. Some terms get a little technical, so we will discuss those in greater detail at a later time. For now we have tried to make things as simple as possible.

In this article we will be covering the terms: air handler, furnace, coil, compressor, condenser, evaporator, expansion valve, refrigerant, and SEER rating.

Excited? You should be…

Air Handler / Furnace
When you have electric heat it is called an air handler. When you have a gas heater it’s called a furnace. Up north you may have an oil burner, but that is also called a furnace. What they all have in common is a fan that circulates air in the house.

Coil
A coil is a heat exchanger. Think of it as the radiator in your car. The radiator is also a coil only with a different name because it’s in your car 🙂

Compressor 
The compressor is a pump. Think of the air compressor you use to fill air in your tires or a high pressure washer. An HVAC compressor is made to pump freon. It may perhaps have a few more fancy attachments to it, but it’s still a pump. When you pump liquids it’s called a pump and when you pump gasses it’s called a compressor.

Condenser
The condenser is where the compressor sits in the outside unit. Later on we will discuss in more detail what a condenser does besides house the compressor. It gets a little more technical.

Evaporator
Your evaporator sits inside with either an air handler or a furnace. This piece will also be discussed in more detail at later time.

Expansion valve
The expansion valve is a metering device. The compressor pumps freon to the expansion valve under high pressure. In the expansion valve pressure is released causing the temperature in the freon to drop several degrees.

Refrigerant
Refrigerant is simply a chemical used in cooling systems for mechanical devices such as the air conditioner in your home or car, refrigerators, or walk-in cooler and freezers.  Simply said: the stuff you put in your a/c to make it cold. The first types of air conditioners used toxic and flammable gases, such as ammonia, methyl chloride, or propane. Most have understandably been taken off the market due to their health and environmental risks, but some are making a come back such as ammonia. Larger refrigeration systems such as ones used in warehouses may use ammonia.

The portion of the Clean Air Act that applies to the Heating, Ventilating and Air Conditioning (HVAC) industry encourages the development of ozone-friendly substitutes for chemicals that contain ozone destroying chlorine, which are called hydrochlorofluorocarbons (HCFCs). The chemical refrigerant of choice for more than four decades, referred to as R-22, is in the HCFC category. R-22 is widely used in heat pumps and AC condensing units to heat and cool homes. Today, a refrigerant called R-410A is used because of its ozone-friendly properties.

SEER rating (more detail)
SEER stands for Seasonal Energy Efficiency Rating and is basically a number describing where an a/c unit falls on the efficiency scale – how much energy an air conditioner unit requires to cool your home. The easiest way to think of this is comparing it to how many miles per gallon a specific car is capable of handling. You might consider buying a Prius instead of a Hummer if gas prices is an issue. The same goes for a/c units – you would buy a unit with a higher SEER rating if you want a lower energy bill.

Concerning residential air conditioners, as of January 26th 2006, new units produces today by law must have a SEER rating equal to or greater than 13. Homeowners are not required to upgrade to a higher efficiency model, but with an average lifespan of about 15 to 20 years low efficiency units (depending on ones definition) will eventually go away completely.

What is HVAC and what does it mean?

Short Answer:
HVAC stands for Heating Ventilation, and Air Conditioning; it represents the technology used in climate control of indoor environments, whether it be in a residential/office building, automobile, warehouse, etc. Based upon the principles of thermodynamics, fluid mechanics, and heat transfer HVAC falls under the sub-discipline of mechanical engineering.

Longer Answer:
The meaning behind HVAC isn’t as difficult as it may sound. The definition is in the acronyms: It’s a system designed to heat, ventilate and condition the air in an enclosed environment. Contrary to popular belief “air conditioning” does not refer to cooling, but rather more general as in changing / alternating the temperature either up or down. It is as if you are conditioning the air to fit your requirements (whether it be up or down is irrelevant). It’s a more modern idea that air conditioning (A/C) entails chilling the air.

The General Idea:

The photo above actually describes the a/c unit in a car, but for educational purposes it’s a little less clustered and explains the general idea.

Any air conditioning unit circulates air using pressure and a few rules of thermodynamics within an enclosed system. The cool air felt from an a/c doesn’t actually come from the freon itself, but rather from the effects of heat transfer. When heat moves it causes a low pressure behind it which feels cool. Ever noticed how one can sometimes feel a gust of cold air blow on you when opening a refrigerator  It’s not cold air from refrigerator  but rather a combination of warm air in the room and a persons own body heat rushing into the fridge. An environment will always want to be in equilibrium, which is why you feel that gust of air even though what you are actually feeling is heating moving away from you.

The following four steps explain the general idea:

  1. The compressor increases the pressure of freon turning it from a gas into a liquid and pushes it towards the evaporator.
  2. Moving towards the evaporator excess heat is ventilated by passing through a condenser and fan.
  3. Once the liquid reaches the evaporator pressure is quickly lowered causing the freon to turn into gas. Thermodynamics demands that heat in an environment to always be in equilibrium. When a liquid turns into gas it undergoes a process called phase conversion. During this process the liquid/gas absorbs heat from it’s surrounding environment making the surrounding air cooler. A fan by the evaporator blows this cold air into the room.
  4. From the evaporator coil the freon is pushed towards the compressor where it once again turned into a liquid and the process starts over.

Some Fun History Stuff:
The process of cooling the air has been around since the early civilizations. The most notable empires to have used some type of temperature regulation are the Roman and the Persian civilizations.

Rome: Only available to the extremely wealthy, the Romans circulated water from their system of aqueducts through pipes in the wall. The circulated water cooled the buildings walls and by that manner cooled the entire home.

Persia:

The Persians used wind ventilation design called a windcatcher or Malqaf in Arabic. A building would be designed with 1 to 8 openings to catch air flow from one or more directions and releasing it causing a draft. This system does not rely on any type of cooling device, but rather relies more on ventilation and air flow to cool the building. (Javaheri)

 

Article References:
“Wikipedia.” HVAC. N.p., 10 2012. Web. 16 Oct 2012. <http://en.wikipedia.org/wiki/HVAC>.

Glass, Nick. “CNN.” Ancient ‘air-conditiong’ cools building sustainably. CNN, 08 2012. Web. 16 Oct 2012. <http://www.cnn.com/2012/02/28/world/asia/ancient-air-conditioning-architecture/index.html>.

Howard, Sawyer. “Coolers Used by Ancient Romans.”eHow – Discover the expert in you.. eHow, n. d. Web. Web. 16 Oct. 2012. <http://www.ehow.com/info_8370402_coolers-used-ancient-romans.html>.

Javaheri, Elyana. “How Ancient Persian Architecture Captured Wind Energy Underground to Green Buildings.” thisbigcity. thisbigcity.net, 20 2012. Web. 16 Oct 2012. <http://thisbigcity.net/how-ancient-persian-architecture-captured-wind-energy-underground-to-green-buildings/>.

Media References:
Image 1: A-C. N.d. Mt. Healthy Auto RepairWeb. 16 Oct 2012. <http://www.mthealthyautorepair.com/A-C.html>.

Image 2: Fellanamedlime, . Malqaf.jpg. 2010. WikipediaWeb. 16 Oct 2012. <http://en.wikipedia.org/wiki/File:Malqaf.jpg>.

How often should you replace your a/c filter?

Searching google on an answer for this topic will show no specific standard as the answer is relative to so many factors. The number of pets you have, the number of people in a home, the amount of overall dust in a home, smokers, etc. However you should inspect your filter at least once a month. If you have pets in your house (dogs, cats) it will require a more frequent filter change than if you did not. People with asthma and/or allergies would benefit of keeping the air filter up to date.

If you do have asthma and/or allergies Trane has a wonderful product called “Clean Effect”  (you can see on their webpage here) This filter can remove up to 99.98% of all airborne allergens that passes through the filter. No need to buy a new filter and even has a light on the front to indicate if it needs to be cleaned.

For the rest of us, who don’t mind buying the cheapest filter at your local shopping center, here’s what you can do: Hold the used filter up to the light and compare it to a clean “spare.” When light is obscured by captured dust and dirt particles, the old filter should be changed. Keep a record for one year and then replace the filter on that basis.

At a minimum, it is always a idea to change filters at the start of the heating and cooling seasons and then in-between according to your need. Also, it is a good idea to have your heating and air system checked at the beginning of heating and cooling season to insure proper operation. You will actually find that all manufacturers of air conditioning and heating units in the United States recommend that you do preventive maintenance once or twice per year by having your unit serviced by a professional.

For more commonly asked question and answers you can follow.our blog or visit the Q&A section of our webpage.