“A lot of people have the perception that a bigger unit is better for the heating and cooling system in their house,” Eric Nekibach, systems integration designer at Cool Heat Mechanical Systems, said. “And that’s really not the case. A properly sized piece of equipment that’s not too large is going to work much more efficiently in maintaining better and more even comfort in your home.”

Alert: Don’t get oversold about systems that are much more expensive than they need to be simply due to their size.

“Sizing” means to literally find the right size or cooling capacity of the air-conditioning system for your home. Unfortunately, many homes have systems that are too big or too small for them. This can lead to a loss of cooling efficiency and high electricity bills.

Components of Air Conditioner Size

There are several components that impact the proper sizing for an air-conditioning unit:

• Geography
• Heating and Cooling Hours
• Windows in the House

There are compressor and other component failures that have nothing to do with the equipment, but with improper sizing or installation of the air conditioning unit.

“If you oversize the cooling system in your house, what will happen is that it will only operate in short little bursts,” Newhouse said. “And since it’s operating for a short period of time, it doesn’t have the opportunity to dehumidify the air in your home.”

When the cooling system is the proper size, it runs a little bit longer every time it turns on, and during this longer period of running, it provides cooling — and it will dehumidify and provide better comfort in the home. So the bottom line is, bigger is not always better.

Even the orientation of the house can have a big effect on sizing of the cooling system. The way the windows are laid out, for example. Do they face north or south? This will certainly increase either the heating or cooling load.

Because sizing is so important in a home’s air conditioning, how that size is determined is crucial.

Construction Advice: When sizing a cooling system for a home, keep in mind that it’s better to undersize than to oversize. A smaller system may run a bit more often, but it will cost less to operate. A larger system will cost more to operate, in addition to being inefficient, which will cost more money in the long run.

One of the main advantages of a well-insulated and well-sealed building envelope is that it takes less energy to heat and cool the home. An efficient building envelope keeps the conditioned air within the home that needs a smaller furnace and/or air-conditioner that is working less often — and this translates into real savings on the utility bills.

But when a home is well sealed a new problem arises — the home becomes a plastic bag, which means any pollutants, such as dust, that may get in the home “stay” in the home. To solve this particular problem, the home needs to be ventilated, and this is where an ERV (energy recovery ventilator) comes into affect.

An ERV pulls in outside air and exhausts the stale air from inside the home, and it does this in an efficient way by using the “exhausted” air to condition — or heat or cool — the incoming fresh air. For example, during the heating season the cold outside air is being tempered with the indoor air via the ERV and, therefore, you’ll be saving a good deal of heated air. The reverse is true in the cooling season.

This means the home should be energy efficient and comfortable during the changing season all-year round.

Change the filter monthly. Other than the regular filter, there are additional ones that can be used, but check with an air-conditioning maintenance person first.

You can get a cap from a hardware store to put on the end of your air-conditioning drain. After capping it, find the end of the drain outside and use a dry vacuum to suck out the dirt. Be sure to remove the cap once it has been vacuumed.

An air-conditioning technician needs to use a high pressure vacuum to clear the drain. It should be done yearly to avoid any backup that could cause mold growth in your air conditioner and water damage to ceilings and walls.

To clean the air-conditioner coils, make sure the power from the unit is disconnected first. Wet the area you are cleaning with a garden hose. Using gloves and safety glasses, spray the commercial air-conditioner cleaner (available at an HVAC supplier) onto the coils. Let it set for a short while and then rinse it down thoroughly with the garden hose.

Step 1: Dismantle the Air Unit

Note: This project requires intermediate to advanced air-conditioning repair skills. Also, check with the manufacturer of the unit regarding detailed repair and warranty information.

Shut down the A/C unit outside and retract the coolant in the refrigerant line to avoid any spills. Only then can the refrigerant line be detached inside. Also disconnect the condensation drain line at the air handler.

Turn the power off at the electrical panel and disconnect the electrical at the air handler. Next, remove the fan system (also known as the squirrel cage) and remove the coil. Lastly, remove the air handler casing.

Step 2: Clean the Air Handler

Begin cleaning the air handler by first vacuuming away dirt caked on the inside of the air handler casing.

To clean the coils, use an antimicrobial solution. When the solution turns the coils white, thoroughly rinse them with a garden hose. Follow the same procedure to clean the fan system (squirrel cage).
rinse coils with garden hose

Step 3: Rebuild the Air Handler

The air handler can now be put back together. Cut new insulated duct board to size so it tucks in and fits snugly around all sides of the handler. Tape all seams with aluminum tape and burnish with a plastic rib. Paint on a coat of mastic adhesive cement to further seal each seam.

Replace panels back onto air handler. Reattach coils and squirrel cage. Reattach the refrigerant line as well as the condensation drain line at the air handler.

Replace the old filter with a new heavy-duty filter

Step 4: Complete the Final Touches

Note: Filters should be changed approximately once a year. If you have pets or allergies, change the filter every six months to ensure a fresh system.

As a final step, install new ductwork in the attic above the air handler, using plastic ties to hold the work in place, ensuring attic air won’t be able to get in from above.

Maintaining a Furnace

• Check to make sure the pilot light is burning. Some furnace units must be lit by hand if the pilot light goes out.
• Follow the instructions for relighting usually printed on access doors. If you have difficulty relighting the pilot light, call a qualified heating contractor for advice.
• Check the blower and vacuum out any dust or debris in and around the unit. Check or replace the filter every 30 days. A dirty air filter clogs the air flow and it can overwork the equipment.
• Lubricate the blower motor.
• Remove the flame shield and check the burner for corrosion. Check flames with the fan off and on to conform to proper operation.
• Check the flue for gaps or dents and make sure it is venting properly to the outdoors.
• Vacuum all the dust from the air registers around the house.
• Check motion and make sure they are clear of furniture rugs, drapes, etc. to let the air flow freely.

Filter Information

Spun Fiberglass Filters are the least expensive, disposable filters. They don’t, however, adequately filter out finer particles.

Pleated Disposable Filters are more costly but will provide four to eight times the filtering capability of the spun fiberglass filters.

Washable Electrostatic Filters have a high initial cost but they are re-useable and offer much higher filtration rates.

There are Electric Filters and Mass Media Filters that offer superior filtration but they require modification to the ductwork for installation. But note that installing these types of filters is not a do-it-yourself project; they should be professionally installed.

At one time or another, most people wish they could heat up one area of the house, perhaps for a visiting grandparent or a new baby. Portable heaters have gotten a bad reputation as fire hazards. In most cases, though, the fires resulted from failure to follow instructions and common sense. Today’s space heaters are safer and more high-tech than ever.

Read the instructions that come with the heater. They are very detailed about how to use it safely. For example, rule No. 1 is that a heater needs to be 3 feet away from any combustible material, such as drapes or bedding.

Never put a portable heater on a countertop. It should be on the floor to minimize the danger of being knocked over and starting a fire. (The exceptions to this rule are models specifically designed for tabletop use.)

Do not use an extension cord with a space heater. Most manufacturers provide a cord that’s long enough to reach the power outlet. However, if an extension cord must be used, use a heavy-duty one. Never use the same kind that might be used for a table lamp. Those cannot handle the wattage space heaters require.

The new portable heaters have some very practical features. For instance, the Holmes Tower Unit has ceramic technology and a blower. It’s adjustable and it turns to distribute the heat evenly throughout the room. It can even be laid on its side and used as a baseboard heater. Many manufacturers include automatic turn-off if the unit tips over. Some have features that sense excess heat in front of it, so if it’s too close to a drape, for example, it will turn itself off before a fire can start.

Bionaire makes a model with a removable thermostat that you place at the other end of the room. It maintains the right temperature throughout the entire space. Some have remote controls with a nightlight feature.

Parabolic models heat only what they “see” instead of heating the air in the room. You point the heater at the chair you’ll be sitting in; you’ll feel the heat, but it doesn’t heat the air around it.

Oil-filled units are probably one of the most efficient units because they actually mimic the idea of a radiator. An electric element heats the units. When they reach the set temperature, they shut down. But since the oil has residual heat, they continue to provide heat.

The Comfort Breeze Duct Booster isn’t a heater, but it can increase the efficiency of an existing system. Slide one over the duct, and it will pull more heat out of the duct and into the room. Wire the duct booster so that it runs only when the HVAC system fan runs for maximum efficiency.

When planning a workshop, keep in mind that if the space is not comfortable it is unlikely that much work will be done in it. For that reason, it’s important to remember heating as part of the workshop design. In addition, adequate ventilation is important from the standpoint of safety as well as creating a pleasant work environment.

Weather Stripping

Maintain a comfortable environment and save money by properly insulating the ceilings and walls in your workshop. It’s also helpful to install weather stripping around doors and windows.

Foam insulation stripping is easy to install around windows. Feel around the edges of the windows to determine whether there are drafty spots. If a draft is found, block it off with weather stripping. Simply clean the surface where the stripping is being installed, peel the paper backing and stick the stripping along the edge of the window.

Heaters

The most common way to heat a shop that’s not attached to a house is with a portable heater. These include radiant heat, electric, propane and kerosene heaters. Here are some options and some considerations:

Kerosene heaters

An advantage of heating with kerosene is that it is inexpensive and lasts a long time. Kerosene heaters are filled via a removable cap. Kerosene does put out an odor that some people find unpleasant. Also, kerosene heaters put out a moist heat, so this may not be the best choice if lumber is stored in the shop.

Propane heaters

The advantage of propane is convenience. These heaters use propane tanks that can be refilled or exchanged at propane stations almost anywhere — including many service stations and convenience stores. Propane tanks are easy to connect to heaters, but when attaching a propane tank, remember that the connection has a left-handed thread, which is opposite from most threaded connections. Propane heaters generally come in two types: ones that are separate from the tank, but connected with a hose, and ones that mount directly on the tank. The heaters that are separate tend to be more stable. Place a tank-mounted heater in a location where it’s not likely to get knocked over, particularly as the fuel begins to run out and the tank gets lighter.

Electric heaters

These heaters come in a number of types and sizes. Quartz-element heaters are a newer style and offer the convenience of a replaceable element. Wire-element heaters are another electric-heater option. Most are equipped with a blower to circulate the heat, so they heat a bigger space more rapidly. Ceramic-element heaters are very popular because they are compact, powerful and efficient. For any type of electric heater, keep the elements clean and free of dust or sawdust.

Ventilation

The easiest way to ventilate your workshop is with a fan; these come in a large array of styles and sizes. Industrial fans, which move large amounts of air, are good for a large space. Oscillating fans move back and forth to enhance circulation. Box fans are inexpensive and particularly handy for a workshop since they can easily be set in a window to bring in outside air, or turned around to draw out stale air.

For a more sophisticated approach, a more elaborate system can be installed using ductwork, air filters and an enclosed fan to move air and return filtered air into the workspace.

Radiant floor heating is a wonderfully efficient heat-distribution system that takes advantage of the whole floor to heat the home, as apposed to forced air coming out of one small vent and trying to heat a huge space.

How does radiant floor heating work?

This innovation in home heating provides warmth for a house from underneath the floors. It’s an effective method of heating that works in an unusual way – hydronics or water going through a PEX tubing in the floor. The water in the tubing radiates the heat into the structure. It’s an efficient and cost-effective way to heat a house.

Running hot water beneath the floor (hydronics) is becoming more popular in residential homes thanks to a flexible plastic tubing called “PEX” — a polyurethane, durable tubing that has a lifespan of more than 100 years. It serpentines underneath the floor and uses the whole floor as a heat-distribution system.

Comfort and efficiency are two reasons why new homeowners like radiant floor systems. Comfort, in fact, is the No. 1 advantage with its warm-feet, cool-head environment. And because the whole floor is used, it’s an extremely efficient system. The aesthetic quality is another reason some homeowners love this system. The heating system remains hidden beneath the floor; there are no vents or radiators in sight. This can be a huge advantage when it comes to interior design.

Three Types of Radiant Floors

There are three radiant flooring systems that can be applied to a home:

• Radiant Air Floors – Don’t hold large amount of heat, and for this reason they are used mainly in commercial buildings.
• Electric Radiant Floors – Do a great job at heating any kind of home, but they’re extremely expensive.
• Hydronic or Liquid Floors – These cost less and are, therefore, used more often in residential construction.

Radiant floor heating is a distribution center for the home by taking advantage of the floor and putting tubing throughout the whole floor, mild temperatures of water and concrete application. Beautiful tile, marble and slate floors are being utilized in homes, but they’re ice cold. With radiant floor heating, it’s possible to have a beautiful floor and barefoot comfort.

Using a hydronic floor system is a great way to heat a home, but it also can be used on a smaller scale, such as in a basement.

Note: Since a radiant floor system is different from a traditional centralized heating system, your builder will need to hire specialized contractors with experience in this area.

Installing a Radiant Floor System

There are two categories of installation for radiant floor heating — wet and dry. Wet installation is most commonly used in the ground floor.

Here are the five steps to the wet installation on a ground level:

• Excavate the area to be heated. This will be the sub-base.
• Add a layer of insulation to create a base over which the rest of the floor system will lay.
• Add rebar to the space. This will add strength to the floor system.
• Add plastic tubing, tying it to the rebar for support.
• Use concrete to create a slab foundation for the floor.

When installing a radiant floor system on the upper floors of a home, the most common method is called “dry installation,” which is a system that suspends the tubing underneath the subfloor, between the joists.

Before each cooling season, it is recommended that central air conditioners get a professional tune-up. This is the biggest step to preventing major malfunctions in an AC unit.

Probably the most important step that can be done by a homeowner is to clean or replace the air filter every month. Electrostatic filters are the best. Do not run the unit with the filter removed. Check the owner’s manual for filter cleaning procedure. Let a washed filter dry completely before reinstalling it.

Every month, especially during the summer months, remove any leaves or debris from outdoor condenser units.

Help keep the outdoor condenser fan running efficiently by cleaning the fan blades and the coils before each cooling season. (Always turn off the power before attempting anything other than superficial cleaning). Remove the fan grill and the fan blades. Gently brush off debris from the blades. Then uncover the condenser coils and gently brush the dirty side. Then hose water from inside the unit, using plastic bags to protect the motor and other components. Also check the base pan (under the unit) and remove any debris that has accumulated there as well.

If the condenser fan makes a clicking or grating noise it may indicate that the blades may be striking an obstruction. If a blade becomes bent, do not try to straighten the blade. A straightened blade may become unbalanced and can loosen the fan motor or hit the condenser coil. Replace a bent blade with a new blade. After replacing a blade, make sure the fan blades rotate freely and don’t wobble. If fan often becomes loose, apply a drop of thread-locking compound.

Keep vegetation at least 2 feet away from outdoor units on each side and above. Aim grass clippings away from the unit when mowing the lawn. During the fall, keep the fan grill free of leaves.

Lubricate the condenser fan motor once a year if it has oil ports. (They’re usually plugged with rubber or metal caps). Use non-detergent lightweight SAE 20 oil and add no more than 10 drops per port.

If possible, shade the outdoor compressor unit. Air in shaded space is typically 5 to 6 degrees cooler than the surrounding air. Proper shading can be up to 10 percent more efficient over a cooling season.

During the winter months, protect the condenser unit with a form-fitting cover. To avoid damaging the compressor, don’t operate the unit when it’s below 60 degrees F outside.

A dirty indoor evaporator coil will hinder the unit’s ability to cool the air moving through the unit. To clean the evaporator coil, remove the front panel of the air handler/ furnace to expose the coil. Ensure that the coil is dry. Use the soft brush attachment on the vacuum cleaner to gently remove any dust or debris from the coil. Check and make sure that coil fins are straight. If not, straighten them with a fin comb available from refrigeration supply dealers.

Warm indoor air contacting the evaporator coils will condense causing moisture to collect and drip. In most units, a plastic pipe carries the water outdoors or to a floor drain. Algae and bacteria growth can clog the pipe. When this happens, backed-up water can puddle, causing rust or other damage. To clean the evaporator drain, remove the plastic tape holding the trap to the pipe elbow. (It may be necessary to saw through the pipe at the elbow). Flush the trap with water from a hose, and then disinfect using 1 tbsp of chlorine bleach. Reattach the trap to the pipe with new tape.

Raise the temperature settings. Each degree of temperature can represent up to 9 percent savings in cooling costs.

Here are some good tips for saving energy and avoiding high heating bills:

• Before purchasing a furnace for your home, check its A.F.U.E. rating, which stands for the Annual Fuel Utilization Efficiency. Each furnace has this rating on it from the factory. The standard is about 80 percent, which measures how much heat goes into the home as opposed to going up the flue pipe. So if you have 80-percent efficient furnace, 80 percent of the heat generated in the heat exchanger is going into your home and 20 percent is going up the flue pipe and is not being used at all.
• If you purchase a heat pump, you’ll want to check its H.S.P.F. rating, which stands for Heating Seasonal Performance Factor. This rating works basically the same as the AFUE rating for gas furnaces. Based on a scale of 1 to 10 (with 10 being the best), a minimum efficiency heat pump will rate approximately 6.6, while high efficiency units will have a rating of 8.0 or higher.
• Change air filters for your heat pump or furnace on a regular basis. A dirty filter increases the air pressure drop in the system, which ultimately uses more energy or decreases the air flow to a point where the system isn’t working properly.
• Have your builder or a heating specialist check the heat ducts for leakage. An HVAC professional can repair any leaks or gaps that are found.
• Weatherize your home by weather stripping or caulking around doors and windows. This will help keep heat from your system inside the home.
• Add programmable thermostats to your central heating system. This will help save energy by not heating your home when you’re away.
• Keep obstructions away from heating vents. This will help promote better heat flow throughout the house.