Heat Pumps

A heat pump works like a normal central air conditioning system. The main difference is that instead of taking the colder months off, the unit must work all year long. When your thermostat senses a need for cooling, the fan in the furnace or air handler comes to life. This fan blows air over a coil containing refrigerant. The outdoor unit contains a pump which is called a compressor. This compressor pumps the refrigerant to the air handler where heat from the air is transferred to the refrigerant. Then the refrigerant is returned to the outdoor unit.

Here another fan pulls air over another coil and the heat is transferred to the outdoor air. This process is repeated over and over until the home is cool.

To provide heat to the home a few components are added to the basic air conditioner. A reversing valve is added to change the direction of refrigerant flow. In the heating mode, this makes the refrigerant temperature higher then the indoor temperature. Therefore, when the refrigerant flows to the indoor unit, heat is transferred to the homes' air.

When it gets below freezing outside, ice can build up on the outdoor coil. This reduces the units' ability to provide the required heat. Therefore, a process is required to melt this ice.

That process is called a defrost cycle. Most units use a timer, a thermostat, or a combination of the two to control this process. When the control senses the need, the outside fan is stopped and the reversing valve directs the hot refrigerant to the outdoor coil. This causes the ice to melt and the process is stopped by another thermostat in the outdoor unit.

To keep from blowing cold air into the home, during this process, backup heat is provided by the furnace.

If you live in an area where it regularly drops below freezing, these units may not be right for you.

If you do live in these areas, you can use these units. But, it is usually a good idea to have a control installed so the unit does not run when it is freezing. This is called an outdoor thermostat. When the outdoor temperature drops below its' setpoint, it can shut off the outdoor unit and use the furnace to provide the required heat.

The latest thing on the market is called a hybrid heat system. This system combines a heat pump with a gas furnace. This control senses which type is more cost effective and switches back and forth as conditions change.

Because these units provide both heating and cooling, it is even more important that you have the proper size. The wrong size unit will steal money from your pocket the whole year long. That can add up in a hurry.

To keep the system running in the most efficient manner, some maintenance is required. Most dealers will provide a service contract but, with some help, you can perform the recommended maintenance. This will also make your system last longer.

Energy conservation

With the help of an energy conservation analysis, we can lower our demand for electricity which then lowers the amount of fossil fuels the power plant must burn. This in turn lowers the carbon dioxide emissions from the power plant but also means that less coal must be mined. Therefore, less fuel for mining equipment is used and CO2 emissions are lowered even more. As you can see, the small steps we take at home can have a much larger effect than we might at first believe.

Heating and Cooling Systems

For the average home, the heating and cooling systems use 30-60% of the total energy consumption. With energy prices on the rise, it is more important than ever to ensure the home is as efficient as possible. The easiest way to save money in this area, is to install a programmable thermostat if you have an older control. You can also explore other methods of cooling the home such as a whole house fan.

Most homeowners are talked into replacing their hvac systems to save money. While it is true that a new hvac system can be more efficient, it may not always be the best use of limited funds. Usually it is better to spend the money on lowering the home's heat gain or loss. Then, your energy savings can help you to pay for those other home improvements such as replacing the hvac system. Improvements to lower the home's heat gain/loss will also allow you to purchase a smaller system when the time comes. This will save you a lot of money!

Start at the top

The attic is a good place to start your energy conservation analysis. If you have little or no insulation, installing or adding more can significantly reduce your home's energy use. You can even add insulation value to your walls and ceilings by painting. With modern coatings and paint additives, you can actually lower the heating and cooling needs of your home by painting. The next time you paint, insulate at the same time.

You should also ensure that the attic has sufficient ventilation. An attic that is not properly ventilated is hotter than one that is. The heat that builds up in the attice is then transferred to the inside of the home through the ceiling. This, in turn, causes the home's air conditioner to run longer and your electricity bill to go up. This can not only save you energy dollars but can make your home last longer.

If the access to the attic is located in a conditioned space, you should ensure that the hatch is insulated. It should also be sealed with weatherstripping or an attic hatch cover.

The home's exterior

Another factor that affects the heat gain or loss of the home is air leaks. You can usually find these by feeling the air come into the home on a windy day.

Old single pane windows are one of the largest sources of these drafts. They typically have wooden frames that have shrunk and leave gaps for the air to enter. If you cannot afford to replace them (or if you rent the home), you can purchase kits to seal them in the winter. These kits usually consist of a clear plastic film and doublesided tape. They are inexpensive and can save you 5-15% on your heating bills.

Another common source of these drafts are the outlets and switch boxes located on exterior walls. You can purchase foam gaskets to place behind the cover plates. They are inexpensive and will pay for themselves in less than one heating season.

Exterior doors are another common source of these drafts. This can usually be cured by weatherstripping around the doors and installing a sweep at the bottom of the door. Both of these things are inexpensive but effective.

Another factor that affects the heating and/or cooling load for the home is the amount of sunlight that enters the home. Have you ever gotten into a car that has sat in a parking lot on a sunny day? If you have, then you have witnessed passive solar heating. This may be good when the weather is cold but when you are trying to keep your home cool it is not. It can be a delicate balance between allowing enough light into the home and increasing the load on your air conditioner.

There are options to solve this problem such as replacement windows with a "low e" coating or dynamic window shades. These blinds or shades can be operated by motors and controlled automatically to keep the warm sunlight out. These units can also be integrated into a home automation system and open/closed based on the temperature in the home.

Home appliances

Next, you should continue your energy conservation analysis by examining your home's appliances. They typically account for about 20% of the home's energy use. The refrigerator, clothes washer, and the clothes dryer are the major users of this energy. If the appliances are more than 10 years old, you should plan on replacing them with energystar qualified units.

The refrigerator's energy use can be minimized with routine maintenance. The coil on the unit which is either mounted on the bottom or the back of the unit should be cleaned at least once per year. This is a simple matter of removing the dust and dirt with a vacuum cleaner.

You should also test the door gaskets on the refrigerator and freezer. This can be done by placing a dollar bill in the door opening, closing the door, and trying to pull it out. If the dollar bill comes out easily, the gaskets should be replaced. It is an easy diy project.

On the clothes washer, you can save energy dollars by lowering the water temperature. It is even better if you wash your clothes in cold water. With advances in detergents, we can now get our clothes clean without using hot water and they will even last longer.

The lint trap on the clothes dryer should be cleaned before every load. You should also inspect the vent for buildup of lent at least once per year.

Saving on the cost of heating the home's water

Your home energy conservation analysis should continue by examining your water heater. The home's water heater can account for about 13% of the home's total energy use. If you have an electric storage heater, then, the thermostats should be set to 120 F. You can also install a blanket to minimize the standby losses. You can also install a timer so that the heater only maintains the water temperature at programmed times during the day.

You may also want to consider replacing the old unit with a tankless hot water heater or a heat pump water heater and save even more. Another option is to install a drain water heat recovery system.

Saving on lighting the home

The next thing to consider in your energy conservation analysis is your home's lighting systems. Nobody wants to sit in the dark or go back to using candles but their are some upgrades that you can do to reduce the amount of electricity required. The home's interior lights typically use 11% of the home's energy. This can be reduced with advanced technology such as compact flourescent bulbs, LED lighting or through passive lighting such as roof windows.

Electricity thieves

Finally, your energy conservation analysis should consider electric loads that are spending your hard earned money even when you think they are off. These are commonly called "phantom loads" and they are prevalent in every home. All of those little lights on appliances, tv, computers, power strips, etc. use electricity and the cost can add up to be significant.

Even in standby modes, many appliances can use 50% of the electricity that is required when they are on. These loads can be conveniently turned off and on with the installation of green switches, smart power strips, or occupancy sensors. The savings can be from 25-45% on the utility bill!

Implementing these ideas

After completion of your home's energy conservation analysis, you can implement these energy saving ideas easily. Instead of just randomly picking things to do, you should come up with a list of priorities based on the characteristics of your home and the climate in which you live. For example, it makes no sense to upgrade your hvac system if you live in an area where you don't use it very often.

If you would like more assistance in conserving energy, you can utilize our consulting services. For a small fee we will assist you in performing an energy conservation analysis as well as designing a customized plan for your home or business.

Basics of home insulation

With this home insulation guide, we will look at the basics of insulating your home and how it can save you a lot of money.

Insulation is the process of separating an area that is warm from an area that is cold. This is accomplished by trapping air in tiny pockets. Air is a poor conductor of heat therefore these tiny pockets help to resist heat flow. This resistance to heat flow is known as R-VALUE.

The R-VALUE of a product is set in the manufacturing process and is determined by the type of material as well as its thickness. There are factors which can cause this value to change after it is installed.

Settling is the process where the insulation material is compressed over time. This process means that less air is trapped in the pockets and therefore it is easier for the heat to flow. (The R-VALUE is lower.)

Another factor that can change the effectiveness of the insulation is moisture. Unlike air, moisture is an excellent conductor of heat. Therefore, any time that moisture is held in a material, more heat is transferred through that material. (The R-VALUE is lower.)

Types of insulating materials

There are four traditional types of materials used in home insulation.

Cellulose is basically recycled paper that is treated to resist pests and fire. It is typically blown loosely into attic spaces or combined with a glue/water mixture and blown into walls. The main advantage of this material is that it is the least expensive. A disadvantage is that it has a high rate of settling (typically 20%). Therefore, it can lose a significant part of it's R-VALUE over time. Another disadvantage is that, when it is blown wet into the walls, time is required before covering it with drywall so that it can dry out. If this is not done, mold and other indoor air quality issues can occur.

Fiberglass is the most common material used in home insulation. Although it is more expensive, it tends to settle less (typically only 1-3%) and therefore it retains it's R-VALUE better and longer than cellulose. Another advantage is that, the material does not retain moisture like cellulose. Therefore, if the material becomes wet, it will dry out and return to it's original R-VALUE. The product is available in blankets which are long rolls that can be cut to a desired length. Blankets are typically used in attics. When these blankets are precut into lengths that fit into wall spaces they are referred to as batts. This material is also available in bags for loose fill. This is typically blown into attics with a machine. (The machine is avaialable for rent at most home centers.) An advantage of this form is that it can fill in hard to reach areas.

Foam is another material commonly used for home insulation. This is available in rigid board form which can be used on the exterior of a home, basement walls, or walls in an unconditioned crawlspace. The spray foam (polyisocyanurate) is a combination of a resin, hardener, and air. It is typically mixed on site and blown into walls and attics. The main advantage is that the material expands when applied and is good at making an air barrier. The product also does not settle and is not affected by moisture. The main disadvantage is it is the most expensive.

The final material is known as a radiant barrier or reflective insulation. This is typically an aluminum foil that is incorporated with a foam board or a bubble wrap type material. Unlike the other materials, this product reflects infrared heat. This material is normally used in attics and on hvac ducts.

Non-traditional types of insulation

The latest innovation is commonly referred to as "blue Jean" insulation because it is produced from recycled denim and cotton. The 90% post consumer recycled fibers are bonded together and formed into a batt for installation. The batts contain a fungal inhibitor to protect against moisture and mold. This is a very environmentally friendly product as there are no chemicals added and therefore no volatile offgassing. Another advantage is that it does not not irritate the skin and therefore is easier to install as no special protective equipment is required.

For situations where traditional forms of insulation are not practical, you can insulate your home by simply painting the walls and ceilings. This can save you money by insulating without the expense of remodeling as well as lowering your utility bills.

How much is needed?

The amount of insulation in a new home is usually regulated by local building codes. These codes typically give the minimum that is acceptable in an area.

In the absence of codes, the following recommendations are generally the most cost effective:

Ceilings should be insulated to achieve an R-49 rating.

Floors over non conditioned spaces should have an R-25 rating.

Exterior walls should have an R-value of 18-22. (typically R-19)

Unconditioned basement or crawlspace walls should be insulated to achieve an R-11 to R-19 rating.

With the rising costs of energy, adding home insulation can be an investment that pays huge dividends.

Air Filters

Air filters protect your hvac system. When we work in a dirty environment, we usually wear a mask to protect our lungs. The filters in your hvac system have the same function. The filter in your hvac system has two main functions. First it helps to improve your home's indoor air quality.

This can improve the health of your family. According to the U.S. EPA, the air inside your home can be 2 to 5 times worse than the air outside.

The second thing they do is to keep your hvac system clean. If the dirt gets through the filter it can clog your furnace's secondary heat exchanger. This can happen if you have a condensing type furnace. If you don't have a condensing type furnace, the dirt will collect on your ac unit's evaporator coil.

Either way, this restricts air flow. This in turn can cause higher temperatures during heating system operation and premature failure of parts. During cooling operation, the operating efficiency will be reduced, your electric bills will go up, and it will cause more wear and tear on system parts.

The filter is usually located in one of the following places:

1. In a grille in your wall or ceiling. These are commonly called return air filter grilles.

2. In a slot on the side, bottom or top of your furnace. It depends on the style of furnace you have.

3. Inside the blower compartment of the furnace. This is common on older furnaces. Most manufacturers do not recommend this on new furnaces.

Air filters have a standard rating. This rating, minimum efficiency reporting value (MERV), is a number from 1-16. You don't have to know all the technical jargon. Simply put, as the number goes up the unit will stop more and smaller particles.

If you decide to replace your existing air filter with one of a higher MERV rating, you should check to make sure you have sufficient airflow after you replace it. This is done by checking the temperature rise in the heating mode and the temperature drop in the cooling mode.

Many hvac units come with a washable type of filter. These will usually be made of foam. These have a merv rating of 1 to 4.

You can also use a disposable type which is normally made of fiberglass. These have a merv rating of 1 to 4.

Usually you can hold those types of filters up and see through them. If that is the case, you know they are not doing their job.

Another disposable type is the pleated filter. These have a merv rating of 5 to 8. These products have more surface area to catch the dirt. They also distribute the airflow more evenly. This means the fan is less likely to pull the dirt through the filter. This is the type of filter that we recommend for most applications. They are the best value in terms of price for the filter and keeping your hvac system clean.

Air filters with the higher MERV ratings are sometimes called allergy filters.

Some are made of advanced materials which set up a static electrical charge. They are called electrostatic filters and are able to capture much smaller particles.

Some come with an antimicrobial treatment. This prevents organisms from living on the filter when they are trapped.

Using the right air filter is only half of the answer though. If it is not replaced often enough, your hvac system operating efficiency will go down. This will cost you on your utility bills as well as wear and tear on the hvac unit.

Most people, even those in the hvac industry, don't change their filter as often as they should. It is usually out of sight and out of mind.

Most hvac service companies offer service contracts where they change your filter. These contracts can be expensive when you consider you can do it yourself.

There are other options if you have special needs such as allergies. The ultimate filter is called a high efficiency particulate air filter(HEPA). These remove virtually everything but the replacement elements can be expensive unless you shop around.

You should also keep in mind that if the filter is a part of the central hvac system and the fan is not continuously running, then most of the time the filter will not be doing anything.