How to Clean Up Home Energy Consumption
July 16, 2014
Homeowners willing to get their hands dirty with cleaning and minor maintenance tasks can improve their home’s energy efficiency. For example, cleaning your refrigerator coils and removing sediment around the water heater tank will keep them working at maximum efficiency. Even properly insulating your attic will prevent ice dams on your roof in winter and unwanted heat in the summer, so heat won’t escape and the air conditioner won’t have to work so much.
In this article, we’ll show you what appliances or areas in your home should be regularly cleaned and checked so energy isn’t being wasted. We’ll even show you how adding faucet aerators and making other minor adjustments can help you conserve water without drastic changes to your lifestyle. Below are some guidelines on how periodic cleaning can add up to saving you money.
Clean Refrigerator Coils Regularly
The coils underneath and behind a refrigerator are dust magnets. Refrigerant is pumped and circulated through the coils as a fan blows room air across them. The moving air removes heat from the refrigerant inside the coils. As the fan sucks air from underneath the refrigerator, it brings along with it dust and dirt that stick to the coils. Removing the access panel from the lower front of the refrigerator can reveal a startlingly filthy sight if the coils haven’t been cleaned in a while.
In addition to being unsightly, the dust on the coils acts as insulation that prevents the fan from efficiently removing heat. Cleaning the refrigerator coils a couple of times a year with a vacuum cleaner and an elongated brush helps the refrigerator operate at its maximum efficiency. Moving a refrigerator away from a wall so air can circulate behind it will increase its energy performance, as will keeping it out of direct sunlight and away from heat sources like a radiator or a range.
As energy-saving tips go, cleaning the coils under your refrigerator probably produces little economic effect compared to the amount of effort required to do the job. But it’s still a task worth undertaking, if only for the hygienic benefit.
Replace the Furnace Filter
The filter on a forced-air furnace performs a valuable function in the home. It strains bits of dust, dirt, and debris from the air stream as it passes through the furnace. This not only improves air quality, but it also protects the inside of the furnace (and air-conditioning evaporator coil, if there is one). Without a furnace filter in place, dirt would build up on the back side of the heater exchanger and inside the evaporator coil. That dirt would act as insulation and interfere with the efficient transfer of heat from the furnace or cooling from the air conditioner to the air passing through it.
But a furnace filter also slows the passage of air through the furnace — especially when it is dirty. The best way to keep your furnace operating at its maximum efficiency is to keep a clean filter inside. That’s one of the only things you as a homeowner can do to maintain your furnace.
Filters can be purchased in bulk and replaced every 30 to 45 days, or they can be vacuumed at those same time intervals. People who own pets may find that their furnace filters need to be replaced or cleaned more frequently, due to pet dander, hair, and dirt brought in from outside.
It is important to remember that in most homes that have a central air-conditioning system, the furnace’s blower is used to distribute cool and dehumidified air during the summer months. Therefore, air passes through the furnace — and the furnace filter — during those months as well. That’s why homeowners with central air-conditioning systems need to change or clean filters in the summertime at roughly the same intervals as they do during the winter. The more freely air can pass through the furnace, the more heat and cooling it can distribute while wasting less energy.
Tune Up Heating and Cooling Equipment
Furnaces, boilers, and air-conditioning systems all have mechanical, moving parts in addition to electrical components. Over time these parts can go out of adjustment and need lubrication and cleaning. Like an automobile, your heating and cooling equipment runs best when it is “tuned up” and all the parts are working together as they were designed.
Tuning up heating, ventilation, and air conditioning equipment, especially the newer, more complicated systems, should be attempted only by service people who have the training and the equipment to do the work. How often should you call for service? For oil-fired systems, the recommended interval is a year. Gas-fired furnaces and boilers and air-conditioning systems should be checked at least every two years.
Just as tuning up a car can yield better gas mileage, the money you spend on servicing your HVAC equipment will pay off in better efficiency — and will also extend the life of the components.
Remove Dirt From Baseboards
Hot water baseboard and electric baseboard heating systems run at maximum efficiency only if the baseboard convectors and radiators are kept clean. These systems depend on air flowing through the many fins that surround the pipes or heating elements. Obstruction of that air — either from dirt and dust buildup or from something covering the top or bottom of the heating units — compromises the performance of the entire system. As is the case with a forced-air furnace, freely flowing air contributes to better efficiency and energy conservation.
Removing or opening the covers that surround baseboard convectors exposes the fins that distribute heat from hot water inside the pipes or heating elements. Vacuuming and brushing the fins, and straightening any that are bent, ensures efficient airflow — and thus efficient heat transfer to the air.
Check Ducts for Leaks During Annual Cleaning
Duct sealing: Keeping ducts clear of dirt will help heat and air conditioning flow properly to all rooms. Scheduling an annual service cleaning also will provide an opportunity to check for leaks.
Here’s a startling statistic: Professional heating, ventilation, and air-conditioning organizations estimate that 25 percent of the air traveling down a poorly installed forced-air duct system winds up somewhere other than where it was intended to go. In other words, some duct systems leak 25 percent of the air passing through them. That leakage might occur in basements, crawl spaces, duct chases, or attics. The bottom line is that you’re not getting all the heating and cooling for which you are paying.
The solution to leaky ducts is duct sealing. While it is tempting to use a product called “duct tape” to do this job, regular duct tape is actually poorly suited for duct sealing. The adhesives in cloth duct tape break down in the presence of heat; eventually the tape fails and falls off the duct.
A product better suited for the task is duct-sealing mastic, available in tubs at heating supply houses, hardware stores, and home centers. To apply duct mastic, dip a gloved hand into the tub, scoop out some mastic, and smear it all around every single joint you can find in your ductwork. The mastic has the consistency of pancake batter, and once it cures it stays on the duct and doesn’t leak.
There are plenty of opportunities in most forced-air heating and cooling systems to upgrade the performance of the ducts. Loosely fitting joints and gaps large and small also should be sealed as soon as possible.
After a sealing job is complete, diverter vanes inside the ducts (if they are installed) might have to be rejiggered and cleaned because air that was supposed to go to a certain area will finally be doing so. The result might be that a formerly cold room is suddenly the warmest one in the house. Also, the furnace or A/C compressor might not come on as often once the conditioned air is getting to where it was designed to go. Duct mastic is inexpensive, the time it takes to seal up your ducts is minimal, and the results can be dramatic.
After duct sealing is complete, it’s time to think about upgrading your forced-air delivery system even further.
Any ducts passing through unheated crawl spaces or attics should be insulated. Heat and cooling thrown off by the ducts in such areas is completely wasted, but if that heat and cooling were retained, the furnace or air conditioner might not have to work so hard to condition the house.
Duct insulation is available in both wrapping and sleeve types. Sleeves are more effective because they have fewer seams, but may require temporary disassembly of the ducts in order to slip them into place.
Maintain a Clear Path for the Air Conditioner
Air-conditioning systems work by moving refrigerant from inside the house to outside. Inside the furnace evaporator coil, the refrigerant absorbs heat from the air passing through the blower compartment. The refrigerant is then pumped outside and flows into a heat-transfer assembly called the condenser. The condenser coils resemble an automobile’s radiator. As refrigerant flows through small tubes in the condenser coils, thin metal fins attached to those tubes extract heat from the refrigerant.
A fan inside the condenser moves air past all the tiny fins and tubes, accelerating the transfer of heat from the refrigerant to the outside air. But this cooling flow of air can take place only when the pathways to the compressor are unobstructed. Landscape plantings, ivy, decks, or benches built over and around the compressor restrict the free flow of air through the system, reducing its efficient transfer of heat. So, to get the most for your A/C dollar, it’s a good idea to keep the outside compressor unit cleared of nearby obstructions.
Because airflow through the condenser is important for the efficient function of a central air-conditioning system, carefully examine the outside of the condenser unit from time to time. The thin metal fins are fragile and can bend if something comes in contact with them — a baseball, lawn mower tire, or edge of a rake, for example. “Fin combs” are inexpensive at heating supply stores and home centers, and they can straighten several rows of bent fins at once.
Cleaning isn’t the only step you can take around the house to help improve energy efficiency. In the next section we’ll talk about strategies for more effective water conservation.
Water Conservation Tips
Improving water conservation in your home can help you save not just on water bills, but also on expenses for heating water. Below are some ideas you can try to boost your water conservation efforts.
Remove Sediment Buildup
Draining sediment from a water heater’s tank is an energy-saving procedure anyone can do quickly and easily. Periodically removing accumulated sediment helps conventional water heaters operate at optimum efficiency. The sediment consists of hard-water minerals and other debris that enter the storage tank along with the incoming water. As the water is heated, the minerals separate from the water and fall to the bottom of the tank.
Over time, the mineral deposits build up to the point that they act as insulation on the bottom of the tank, isolating the water from effects of the burner firing below (on gas and oil units) and sometimes stacking up high enough to cover the heating element on electric water heaters. The harder it is for heat to get through the sediment layer, the longer the burner has to fire or the electric elements have to run in order to heat the water.
The solution is to remove the sediment layer. You do not have to turn off the power source (electricity, gas, or oil) to the water in order to drain the sediment.
A small drain valve is on the outside of the water heater tank’s jacket near the bottom. It looks like a miniature hose bibb on the outside of a house. Attach a short length of standard garden hose to this valve, stick the free end of the hose into either a floor drain nearby or a large bucket, and open the valve.
Water will flow from the bottom of the water heater and out the valve and through the hose, taking sediment along with it. After draining five gallons or so from the tank, shut off the valve, disconnect the hose, and empty the bucket (if you used one) into a sink or toilet. You’ve not only improved the efficiency of your water heater, but you’ve also extended its service life.
What is the reason? There is a thin film of water that is trapped between the sediment and the bottom of the tank. When the burner fires, the thin layer of water heats to an abnormally high temperature that deteriorates the tank’s glass lining, speeding up its rusting process. Accumulated sediment is also responsible for the popping, banging, rumbling, and percolating noises often heard from a water heater as the burner fires or the elements heat up.
Depending on the mineral content of your water, a water heater tank should be drained of its sediment at least twice a year, and more often in hard-water areas.
What does pipe insulation do? It keeps heat inside the pipes where it belongs, rather than radiating out into the air. The result is that hot water reaches distant bathrooms faster than it would otherwise, reducing the volume of water that has to flow down the pipe for hot water to effectively arrive. And once hot water fills the pipe, it stays there for a long time. So if you use a hot water tap again shortly after the first usage, it’s likely that the water will still be sufficiently hot.
In addition, pipe insulation helps reduce “standby” heat losses at the water heater. Standby heat losses occur while the water heater is just sitting there doing nothing at all. Over a period of time, heat radiating from the water heater’s tank and the pipes entering and exiting the top of the unit reduce the temperature of the water inside the tank. Eventually, the thermostat is activated and the burner fires or the electric elements switch on. The water heats up again, only to cool down gradually through the cooling effects of the tank and pipes. It’s an endless cycle, exacerbated by the heat loss through the pipes at the top of the water heater. So, although the hot water pipes are the logical ones to insulate, insulating the first five feet or so of the cold water pipe at the water heater is a good idea, too. That helps reduce the loss of heat that migrates up the pipe from the water heater tank.
Although insulating the pipes at the water heater might eliminate only one burner firing or element activation a day, at today’s gas and electric prices, that can add up to substantial savings over the course of a year.
It may also be worthwhile to insulate another cold water pipe in your house — the water service entry pipe from a municipal supply or well — though not for energy-efficiency reasons. Throughout the winter and into the spring, water coming into the house through that pipe is cold. If the air is humid enough, condensation can form on the outside of the pipe and drip down onto carpets, suspended ceiling tiles, and anything else along its path. Covering the exposed pipe with foam insulation isolates the pipe from the humid air, preventing condensation from forming.
Insulating water pipes used to involve a large roll of itchy fiberglass insulation, a lot of time, and a lot of cutting and fitting the wrapping around obstructions. And even after all that work, the insulation was so thin that it didn’t do much good. Insulating the water pipes in your home these days is simpler, quicker, and more effective.
The closed cell foam pipe insulation available at plumbing supply houses and home centers not only insulates far better than the old fiberglass material, but it’s also easy to install. Each piece is slit along its length, allowing the insulation to simply snap over the pipe. The foam is so soft that it can be cut with a kitchen knife or a pair of heavy scissors.
Add a Blanket to the Water Heater
New water heaters are being built with better insulation these days, so if you have an old unit, don’t be shy about adding an extra layer of insulation. There are water heater “blankets” available at home centers and hardware stores that wrap the exterior of the unit with an additional layer of insulation.
Electric water heaters can be covered top to bottom with insulation. Gas water heaters, however, must not be covered on top or along the bottom. The top contains the flue, and that can get hot enough to ignite flammable materials. The bottom must be left open so air can enter the burner assembly for proper combustion of the natural gas, propane, or oil.
The end of the pressure and temperature relief valve extension pipe (usually running down the side of the unit) on any type of water heater must be left open and exposed as well. This pipe has to be free of obstructions in case the valve activates and releases hot water or steam. Any blockage could interfere with the free release of the pressure within the tank, and that could be dangerous.
Other than that, the more insulation you can wrap around a water heater, the fewer “standby” losses will occur, the less the burner or elements will come on, and the more efficient it will be overall. This is a relatively easy and inexpensive task that pays off every hour of every day from the moment you put the blanket on. Like most jobs involving insulation, it’s not glamorous, but it works.
Install Reduced-Flow Showerheads
Nearly half of all water used in a home is used for bathing. Almost all of that water needs to be heated. Therefore, the bathroom is an ideal place to practice energy and water conservation. Since January 1995, showerheads in new homes have been required to dispense no more than 2.5 gallons per minute. If you have a showerhead older than that in your home, it takes but a few minutes to replace it with a showerhead that meets the modern flow rate standards.
Showerheads aren’t expensive. Ten to twenty-five dollars will purchase a new one that meets the 2.5-gallon limit. If you have an older showerhead that allows up to 6 gallons a minute and subsequently install a low-flow showerhead, you’ll reduce your shower water use by more than three gallons per minute.
Water entering a home in northern states in the winter can be as cold as 38 degrees. Heating water that cold to the 120 degrees or so needed to produce a reasonably hot shower demands quite a bit of energy. So it’s easy to understand why taking advantage of 2.5-gallon showerhood technology can save a lot on your utility bill.
A caveat though: Putting a low-flow showerhead into use is not an excuse to spend more time in the shower. In some cases, the length of time a person spends in a shower is exactly equivalent to how long the hot water in the water heater’s tank lasts. Once the hot water runs out, the shower is over. If it took, say, ten minutes to exhaust your water heater’s capacity with a six gallon per minute showerhead, does that mean you can now stay under the running water for 20 minutes with a reduced-flow showerhead in place? Technically, yes. But that would result in no energy or water savings. If you confine your shower activities to simply washing, rinsing, and then getting out, keeping the shower’s length the same as it was before the introduction of the new showerhead, you’ll decrease your use of energy and water.
Use Faucet Aerators
Older-style bathroom and kitchen sink faucets can deliver as much at 3.5 to 5 gallons of water per minute. Much of that water is wasted; typical washing tasks can usually be accomplished using less.
Faucet aerators, either supplied on new faucets or as inexpensive retrofit add-ons to older faucets, reduce the flow rate to 0.5 to 1.0 gallon per minute in bathrooms, and 1.0 to 2.0 gallons per minute at the kitchen sink. Because air is added to the water stream at the faucet’s tip, the flow seems full although the actual volume of water is substantially reduced. This allows you to do more with less hot water.
In the next section, we’ll look at another important step you can take to conserve more energy. If ice dams form on your roof during the winter months, it’s important to address the attic ventilation problems that caused them.
Eliminating Ice Dams
If you have ice dams forming on your roof during the winter, it means that heat is escaping the house and leaking into your attic. Ice dams are the manifestation of energy inefficiency in a home. They are the result of poor air sealing, a lack of insulation, and inadequate ventilation in an attic.
Warm air travels upward because of its natural buoyancy. As it reaches the ceiling in the top floor, it seeks ways to rise even higher through cracks and gaps in the ceiling and walls. Some of those pathways are obvious; many others are not. As discussed in earlier chapters, openings around and through recessed canister lights, whole-house fan installations, attic-access hatchways and pull-down stairs, and electrical boxes in the ceiling and walls all provide conduits from the house into the attic. Additionally, heat is conducted upward through the top-floor ceiling through inadequate attic floor insulation. The result of the air leaks and conducted heat is an accumulation of warm air in the attic.
When snow falls on top of a roof, it acts as insulation, protecting the roof surface from the outside cold air. The combination of heat from below and snow on top creates conditions that warm the roof sheathing and shingles.
The warm shingles melt the snow that covers them, and that water runs down the roof, under the snowpack that lies on top of the roof. As the water reaches the roof edge, there is no longer any heat from below to warm the shingles and sustain the melting process. The water freezes along the overhangs and starts to build into ice dams.
As the ice dams build up higher over the course of the winter due to the constantly melting snow on the roof, water starts to form ponds behind the dams. Eventually, if the water level gets high enough and if the roof is inadequately protected from water intrusion, it starts to seep in underneath the shingles. In the worst cases the water can penetrate into the soffit areas, get behind the siding, and even enter the house through the interior ceilings and walls. Ice dams can be very destructive and result in millions of dollars in insurance claims every year.
The root cause of ice dams is excess heat in the attic. Undertaking the air sealing and insulating measures described earlier in this book will help reduce the heat leakage problem. The idea is to make the attic as cold as possible — as cold as the outside air — to reduce or eliminate the snow melting that starts the ice dam formation process. Additional ventilation in the attic also exhausts any heat that does manage to make it up there.
The ideal ventilation scheme involves several components: soffit vents that introduce air into the attic under the eave edges; air channels; chutes that hold insulation back from the underside of the roof sheathing and direct the air upward from the soffits into the attic; and high roof or ridge vents that convey the air to the outdoors. The chutes are important because insulation lying against the underside of the roof sheathing forms a thermal bridge that allows heat from the house below to travel through the insulation directly to the sheathing. It is essential to break that thermal bridge to eliminate the direct conveyance of the heat to the sheathing and to promote the free flow of air into the rest of the attic from the soffit vents.
Attic ventilation is also needed to reduce moisture concentration in the attic environment. Air that travels into the attic from the house below carries water vapor. Unless that moisture is vented away, it can condense on the cold insulation, framing, and sheathing. If allowed to continue, the wet surroundings can create conditions conducive to mildew and mold growth, and can even rot.
Adequate attic ventilation also pays off in the summer. Air flowing through the soffit vents and up through the ridge or high roof vents exhausts heat. Venting the attic means less heat is transferred downward through the attic floor insulation and into the house below. Therefore, the A/C doesn’t have to run as often, which conserves your energy dollars.
Comprehensive air sealing, insulation, and ventilation can reduce or eliminate the formation of ice dams on your house roof in the winter while paying dividends in the summer. Plus, this type of energy-saving upgrading is a onetime event in the life of the house. Add vents and insulation and perform air sealing, and you’ll never have to worry about it again.
Simple tasks such as cleaning refrigerator coils, installing reduced-flow showerheads, and properly insulating the attic area can help your home become more energy efficient. Follow the guidelines in this article and let the little tasks add up to big savings.