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"The thermostat has a device inside it that is intended to keep the furnace from overshooting the set point," he said.
This device shuts the burner off slightly before the room reaches the set point. The fan continues to operate, usually delivering enough heat for the room to reach the set point.
"If this device, the anticipator, is adjusted incorrectly, it could shut off the burner too soon and never allow the room to reach the desired temperature set point," Meyer said.
The thermostat anticipator is usually adjustable. "Ideally, the slide should be positioned to point to the ampere rating of the gas valve," Meyer said. "If this is unknown, set the anticipator to a larger number."
On digital thermostats, you will need to read the instructions to determine how to adjust the anticipator.
"A second cause of furnace cycling could be a misadjusted or faulty high-limit switch," he said. "This switch shuts off the gas valve if the furnace overheats."
In either case, it is probably best to have a service professional check out the unit. Failure to reach the desired set point indicates there is a problem with the furnace or controls.
While some home owners might be able to determine and correct the problem, it is best to have a service person check the system. If the high-limit switch is the problem, it should be replaced immediately.
"The drying cycle of a dishwasher consumes from less than one-half to about one kilowatt-hour of electricity, depending on the age and model of the dishwasher," said Doug Walter, president of Kansas Building Science Institute, Manhattan.
"If you wash 30 loads of dishes a month, you will save from 75 cents to $2.40 by omitting the heated drying cycle (assuming a rate of 8 cents per kilowatt hour)," he said.
"We typically use the term cogeneration to describe the production of two forms of energy from a single energy source," said Dennis Matteson, extension mechanical engineer at Kansas State University.
"The more common cogeneration applications use fuel such as natural gas to produce electricity and thermal energy," he said.
The feasibility of cogeneration depends on the cost of the fuel used, the value of the energy produced, the quantity of usable energy produced, and the cost of financing.
"Cogeneration is most often used in facilities where there are large electrical and thermal loads," Matteson said. "The thermal load may be either steam or hot water."
The unit may be either a stand-alone unit, where all the electricity is generated by the cogeneration unit, or the generator may be connected to the electric power company.
"Compact fluorescent lamps are a better deal than incandescent lamps even if you got the incandescent lamps for free," said Doug Walter, president of Kansas Building Science Institute in Manhattan.
"Compact fluorescent lamps use one fourth the energy and last 10 times as long as incandescent lamps," he said. "Not only do you avoid the annoyance of replacing the incandescent lamp over and over again, you'll save at least $20, and as much as $40, over the life of the compact fluorescent lamp. That's over and above the cost of the lamp."
Compact fluorescent lamps now come in a wide variety of shapes, sizes and wattages that will fit into many light fixtures.
If warm, moisture-laden interior air finds its way into the wall, and the inside face of the foil is cool enough, condensation could result. If the inside vapor barrier is carefully installed and sealed to prevent air leaks, this potential is significantly reduced.
"The other factor affecting the potential is the temperature of the inner foil face," Snead said. "The high R-value of this sheathing reduces the likelihood that the foil face will be consistently cold enough to sustain condensation."
Shoddy installation of the sheathing could allow air leakage into the wall from the exterior. This could vent moisture-laden air to the outside, or allow cold incoming air to cause spot moisture problems inside the wall.
"The sheathing should be installed to be an air barrier and reduce infiltration," Snead said. "Taping the seams, corners, and butt joints with other materials has been shown to be very effective at achieving an airtight wall."
The performance of any wall or building system can suffer from poor installation. Careful attention to details and evaluation of how they will respond to air and moisture is essential in any successful building system.
"Furnaces need the cooling action of air flowing through the furnace to cool the unit," said Gene Meyer, extension mechanical engineer at Kansas State University. "Closing off too many registers will restrict the air flow and reduce the cooling action."
Furnaces are equipped with a safety device that closes the main gas valve when the furnace overheats.
"But it is not a good idea to use the safety switch as a controller," Meyer said. "No more than two out of 10 registers should be closed at one time."
"After you have closed a couple registers, let the furnace go through a long heating period," he said. "Turn your thermostat up and check for anything unusual such as the gas valve cycling off and on. If things don't seem right, open the registers."
"In all likelihood, your new furnace has a smaller capacity than your old furnace," said Doug Walter, president of Kansas Building Science Institute, Manhattan.
"Furnace sizing procedures have changed considerably in the last few years," Walter said. "It's not uncommon to find older furnaces oversized by 50 to 100 percent."
Today, furnaces are oversized by no more than 15 to 30 percent.
"A smaller furnace capacity means the furnace will run more of the time to provide the same amount of heating a larger furnace provides," he said. "But because the fuel input is less, the smaller furnace uses no more energy than the larger furnace."
Because your new furnace is a high-efficiency model, it will save you energy by sending less heat up the chimney, even though it runs more.
"I can speak from experience in saying that many of my own windows also frosted over as a result of this several blast of arctic air," said Gene Meyer, extension mechanical engineer at Kansas State University.
"In my case, I forgot to readjust the humidistat controlling my humidifier," he said. "As a result, I was adding too much moisture to my home. This caused a condensation problem and frost to form on my storm windows. Once I readjusted the humidistat, the frost gradually disappeared."
However, he added, it is not unusual to find a small amount of frost on windows shortly after the weather suddenly turns extremely cold.