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MECHANICAL ROOM

In many homes, electricity, water, the heating system and cooling system originate in a mechanical room from which wires, pipes and ducts snake through floor joists and walls delivering power and water, etc. to where it is needed. Decisions made about what goes into, and how we monitor what comes out of, the mechanical room can have a great impact on a home's energy efficiency.

Water Heater...Water heating accounts for 20% or more of an average household's annual energy expenditures. To save energy and money in this area follow these suggestions:

Set your hot water heater to 120 degrees Farenheit. To test your hot water's temperature, fill a basin with very hot water and submerge the probe of a meat or candy thermometer in the water. Adjust your tank's temperature dial up or down and retest until you reach the desired temperature.

Insulate your tank if it is located in an unheated space to save energy.

A storage tank-type water heater raises and maintains the water temperature to the temperature setting on the tank even if no hot water is being drawn. Tankless hot water heaters (also called "demand" or "instantaneous") are far more energy efficient because they heat water only when you need it. You could save 67% on water heating. Though tankless water heaters cost more than conventional storage tank-type units, tankless heaters are more efficient, cost less to operate, and last longer, so you will save money in the long run.

Heating Systems...Heating and cooling account for 50 to 70% of the energy used in the average American home, so this is an area that demands attention.

Ductwork for forced-air systems can leak more than 25% of the heated air! And if ductwork runs through unheated spaces, additional heat is lost. It's worth the money to pay for a professional inspection of your duct system, and make recommended improvements that will minimize air leaks and improve insulation.

In forced air systems, it is a good idea to replace or clean the air filters monthly during the heating season to help the furnace work at optimal efficiency. Filters that are made cheaply to be disposed of each month are less desirable than those that are designed to last years with periodic cleaning.

Heating with baseboards allows heat in each room to be controlled seprartely. If you have baseboard heaters, take advantage of the opportunity to regulate heat in individual rooms. Keep the bedrooms at 64 degrees, the family room and kitchen at 68 degrees, the bathroom at 70 degrees and completely shut off heat in rooms that are unoccupied. Baseboard heaters should sit at least three-quarters of an inch above the floor or carpet to allow the cooler air on the floor to flow under and through the radiator fins so it can be heated.

Radiant heating can be more efficient that a forced air system because heat doesn't travel through ductwork. With radiant heat occupants can feel comfortable at lower indoor air temperatures, saving around 5% of space heating costs, according to manufacturers.

Hydronic radiant floor heating can be more efficient, and cost less, than electric systems because the water can be heated by means other than electricity, which in many parts of the country comes from coal and is expensive.

Adding thermal mass to a radiant heating system, for example by embedding the system in a concrete floor, can increase efficiency because the mass will store heat and release the heat into the room long after the system has been shut off.

A heat pump moves are rather than creating air, and as a result can provide up to 4 times the amount of energy it consumes. If you live in a climate that does not experience prolonged periods of sub-freezing temperatures, a heat pump could be an energy efficient choice.

Cooling Systems

An outside cooling unit should be in a cool, shaded place two feet from the North or East side of your home.

If your AC is in direct sun most of the day, plant a shade tree that will provide maximum shade for the unit during the hottest part of the day.

Replace or clean dirty air filters once a month during peak use. A permanent filter that you can wash instead of replace may be preferable as long as it doesn't resitrict air flow too much. Ask your system's manufacuter.

Air must be able to circulate around an AC unit, so clear away brush and branches that may be restricting air flow.

Ceiling fans can help reduce AC use by allowing you to feel cooler at a higher thermostat setting (e.g. 82 degrees). For fans to work properly, there should be a clearance of at least 6 inches between the ceiling and the blades to allow for sufficient air to move around the blades.

A whole house fan can cool a house at a fraction of the cost of air conditioning when the outdoor temperature is cooler than the indor temperature, such as at night. Installed in the attic, a whole house fan will pull cool air through the house and exhaust warm are to the outside.

Duct systems for central air conditioners can leak 30% or more of the cool air! If you use a cental AC, pay to have a professional inspect and, if necessary, improve your duct system.

Thermostat

Install a programmable thermostat that combines a clock and a thermostat to automatically setback temperatures when you will be away or asleep. A programmable thermostat is convenient and very effective at saving energy.

In the winter, set your thermostat no higher than 68 degrees Fahrenheit. This temperature may feel cold if you are not dressed for the season. It's appropriate and reasonable to wear long pants, socks and two layers on top inside during the winter. Avoid fabrics like cotton which has no thermal value. The best fabrics for winter are wool and polar fleece.

Lowering your thermostat at night and when the house will be unoccupied by 10° could lower your overall heating bill by 20%.

If you must use air conditioning, set it as high as is comfortable; for most people this range is between 78-80 degrees Fahrenheit. For each degree above 78, you'll save 6 to 8 percent in cooling costs. At night urn off the AC if you can and use the Fan setting.


Heating and Cooling Resources

The Consumers Guide to Energy Efficiency and Renewable Energy and EnergySmart Library Information on energy products and technologies for your home.

energystar.gov Look up energy efficient heating and cooling appliances and products.

homeenergytuneup.com Get help findng where you are wasting energy.

Tankless water heaters

Washable air filters

Whole house fans

Programmable thermostats

 

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