Is your heating unit or furnace is not blowing hot air, is it noisy or doesn’t come on at all or Thermostat doesn’t work? For any of these problems or any other heating unit or Thermostat issues, we are on call to help 24 hours a day, 7 days a week at:
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How your central heater works
The majority of residential central-heating systems are fueled by natural gas or oil; some, however, are powered by electricity and it is with those that we are concerned here. (Gas- or oil-fired furnaces are best left to someone licensed to handle those systems. The dangers involved are very real —so much so that, in many areas of the country, it is illegal to work on one without the proper certification.) As a rule, the heat is automatically controlled by means of a thermostat, just as most air-conditioning units are. When the temperature goes below the thermostat setting, the bimetallic contact strip energizes an electrical circuit which turns on the heating elements and blowers. Once the temperature reaches the setting on the thermostat dial, the thermostat automatically turns off the source of heat.
There are two basic types of electric heating systems: gravity warm-air and forced warm-air. Gravity systems operate on the principle that hot air rises, since it is lighter than cooler air. A gravity system works efficiently only in homes with basements, or in multi-story buildings, where the central heater is below the normal living level. The heating elements generate heat when electrical energy passes through their coils, and the hot air then rises through ducts. Usually the air movement is augmented by fans. During the upward heat movement, warm air displaces the colder air, which then drifts downward through a series of “cold air ducts” until it reaches the lower part of the central element, where it is heated and again repeats the same cycle. Gravity warm-air devices are used in floor furnaces and some space heating systems. Several smaller heating elements and associated blowers are placed either under the floor or at the baseboard of the area to be heated.
The biggest shortcoming of gravity systems is that there must be a large temperature difference between the upward-moving hot air and the cold air it is to displace in order to create good air movement and equal distribution of heat throughout the home.
Forced warm-air heaters utilize a blower to force air from the heating element through the duct work and registers into individual rooms. Use of this system minimizes the temperature differential between the warm air from the heater and the cold air leaving rooms through return vents. The forced air system allows users to control whole house heating, and to have better control over the heating to individual rooms and areas. Often the building is divided into segments, with each area having its own thermostat and individual blower or auxiliary fan support system.
Repair and maintenance of an electric heating system is simple. Some systems have emergency switches, as well as a standard service entrance fuse or breaker. The emergency switch for an electric furnace is a wall switch close to the heater, and it is generally red. When the heater fails to operate, first check that no one has accidentally turned this switch off. If all switches, fuses and breakers are working, try moving the thermostat up a few degrees. If the thermostat has a day and night setting with a timer, take off the thermostat cover and check the dial to see if a power failure or some accident may have caused the timer to get out of cycle. While this cover is off, check the thermostat contact points. Dirt or corrosion on the bimetallic contact points could keep the heater from being energized. To clean these contacts, pass a business card or a crisp, fresh dollar bill between them.None found.