Feders Air Conditioning, Heating, Appliances, Plumbing & Electrical Service & Repair Center

To be without furnace in Agoura Hills, Alhambra, Altadena, Arcadia, Artesia, Azusa, Baldwin Park, Bell Gardens, Bell, Bellflower, Beverly Hills, Buena Park, Burbank, Calabasas, Canoga Park, Canyon Country, Carson, Cerritos, Chatsworth, Compton, Covina, Culver City, Downey, Duarte, El Monte, El Segundo, Encino, Gardena, Glendale, Glendora, Granada Hills, Harbor City, Hawthorne, Hermosa Beach, Huntington Park, Inglewood, La Canada Flintridge, La Crescenta, La Habra, La Palma, La Puente, La Verne, Lakewood, Lawndale, Lomita, Long Beach, Los Alamitos, Los Angeles, Lynwood, Manhattan Beach, Marina Del Rey, Maywood, Mission Hills, Monrovia, Montebello, Monterey Park, Montrose, Newhall, North Hills, North Hollywood, Northridge, Norwalk, Pacific Palisades, Pacoima, Palos Verdes Peninsula, Panorama City, Paramount, Pasadena, Pico Rivera, Playa Del Rey, Redondo Beach, Reseda, Rosemead, San Fernando, San Gabriel, San Marino, San Pedro, Santa Clarita, Santa Fe Springs, Santa Monica, Sherman Oaks, Sierra Madre, Simi Valley, South El Monte, South Gate, South Pasadena, Stevenson Ranch, Studio City, Sun Valley, Sunland, Sylmar, Tarzana, Temple City, Thousand Oaks, Topanga, Torrance, Tujunga, Universal City, Valencia, Valley Village, Van Nuys, Venice, Walnut, West Covina, West Hills, West Hollywood, Westlake Village, Whittier, Wilmington, Winnetka or Woodland Hills during the cold Southern California months of December, January and February in the year 2011-2012 is to put you and your family under potential cold duress, as the temperature inside your home can easily get below 40ºF in the middle of the night making it extremely uncomfortable to stay inside during the evening and almost impossible to sleep comfortably at night.

Feder’s Furnace Repair technicians are capable and available to service your current furnace or recommend an alternative heating system if that is your need. Our furnace repair technicians know the most appropriate diagnostic techniques and methods to determine the best approach to heating your home and the most cost effective parts and equipment to meet your heating needs.

Feder’s Furnace Repair technicians will work with you to increase the energy efficiency of your home furnace and to keep the cost of running the system at its minimum. To speak with one of our furnace consultants or schedule a service call with a technician, call us at 888-353-8444

Furnace Repair System Operation

The experts at Feder’s Air Conditioning, Heating, Appliances, Plumbing & Electrical Service & Repair Center are pleased to share the following information that explains the major components of a furnace and how a furnace works.

A household furnace is a major appliance that is permanently installed to provide heat to an interior space through intermediary fluid movement, which in most cases are air or steam. The flame originates at the burners and is drawn into the heat exchanger by the negative pressure produced by the draft inducer. The hot gases produced by the combustion of the flame pass through the chambers of the heat exchanger and heat the metal walls of the heat exchanger. The gases cool as they transfer the heat to the heat exchanger and are at about 120 °F (50 °C) as they exit on a high efficiency furnace. The cooled gases then enter the draft inducer blower and are pushed into the venting pipes. The exhaust gases then are directed out of the house through the vent pipes.

The controls include the gas valve, ignition control, ignitor, flame sensor, transformer, limit control, blower control board, and flame roll out switch. The transformer provides 24 volts of electricity to power the controls. 24 volts is applied to the thermostat that is installed in the living space.

The thermostat is basically an automatic switch that closes and completes the electrical circuit when the room temperature drops below the heat setting. This then allows 24 volts to the circuit board which initiates the heat sequence. The circuit board has a relay that closes to power up the motor on the draft inducer blower. Then the circuit board ignitor relay is energized which sends 120 volts to the hot surface ignitor and makes it glow bright and get extremely hot.

Next the gas valve relay in the circuit board is energized. This allows voltage to the gas valve and energizes a solenoid coil in the gas valve which opens the valve to allow gas to flow to the burners. The gas flows into the burners and is ignited by the hot surface ignitor. The ignition control circuit board applies an AC voltage to the flame sensor which is just a stainless steel rod. An interesting thing occurs inside a burning flame, which is called ionization. That is, free electrons are produced which can conduct electricity through the flame itself. The electrons will normally flow from the flame sensor, through the flame when present, and back to ground through the grounded burners.

The ignition system must prove that a flame is present to continue the gas flow, or if there's no flame, then shut off the gas flow through the gas valve to prevent a possible explosion. It also must not be fooled into thinking there is a flame present by a flame sensor that is touching the ground from being broken or bent. The way it does this is by a diode effect where the sensor surface area is less than 10% of the ground surface area. This produces a half-wave of electrical current from each full wave. The ignition control circuit detects the half-wave to determine if the sensor is merely touching ground. If the ignition control receives this half wave signal from the flame sensor then combustion will continue.
Now the circuit board timer counts a determined amount of time and energizes the blower relay. This relay powers up the blower motor and air is then pushed through the heat exchanger where it removes the heat from the hot metal and enters the ductwork to go to the various rooms in the house. The limit control is a safety device that will open the electrical circuit to the ignition control and stop the gas flow if the furnace overheats. The flame roll-out switch does the same thing if the flame was rolling out of the heat exchanger instead of being completely induced into it by the draft inducer.

The blower creates a negative pressure on the intake side which draws air into the ductwork return air system and blows the air out through the heat exchanger and then into supply air ductwork to distribute throughout the home