8 Steps to Repair a Furnace - Identification and Troubleshooting of a Gas Furnace

The gas oven

The gas oven is a device with the appearance of a large box that does the following:

• Takes cold air,
• Clean it with an air filter,
• Heat it with a gas burner using a stainless steel heat exchanger,
• Distributes the hot air with a blower through the network of ducts of his house

The hot air then cools in the different rooms of your home and returns to the oven through back grilles and ducts.

Returning cold air enters through the oven air filter to complete another cycle.

Sometimes there is a humidifier mounted in the oven or in the return air duct.

Ovens come in different efficiencies that are measured in AFUE.

Occasionally things do not work the right way and you need to troubleshoot a gas oven or turn on a permanent pilot if you have one. Most new furnaces have electronic lighters and require special problem solutions.

Let's look at the most common problems and repairs you might need to make.

1. The gas oven does not produce heat

Possible causes

• The thermostat is set too low and does not require heat
• The thermostat does not work
• The switch or fuse controlling the oven is fired or blown
• The natural gas or propane valve is closed
• The pilot is off

Possible repairs

• Check that the thermostat is in warm mode and has a proper temperature setting
• Try moving the graduating knob up or down a couple of degrees
• Clean the thermostat contacts if it is a non-digital model
• Reset the tripped switch
• Replace the blown fuse
• Turn the pilot light on

2. The gas oven turns on and off too frequently

Possible causes

• The oven air filter is dirty
• Problem with blower motor
• Problem with heat anticipator (thermostat)

Possible repairs

• Adjusts the thermostat heat anticipator
• Also see troubleshooting a thermostat
• Replace the dirty air filter
• Oil the blower motor lubrication ports (usually at each end of the shaft) with light oil
• Check that the belt is adjusted. The band should hang more or less 1 "to the center of its extension.
• If it is too loose, tighten the band.
• Replace the frayed belt.

3. The gas oven blower does not shut off

Possible causes

• The thermostat is set to continuous fan
• The oven fan switch is broken (if the thermostat has no fan setting)

Possible repairs

• Change the thermostat fan setting
• Reboot or replace oven fan control switch

4. The oven has noisy operation

Possible causes

• The sharp "screech" sound may be caused because the blower belt is slipping or the motor shaft bearings need to be greased
• The bass "boom" sound can be caused by an incorrectly adjusted pilot light if this problem occurs with the burners off.
• A more serious "boom" sound may be caused by dirty gas burners if this problem occurs with the burners on.

Possible repairs

• Oil the engine lubrication ports (usually at each end of the shaft) with light oil
• Check that the belt is adjusted. The band should hang more or less 1 "to the center of its extension.
• If it is too loose, tighten the band.
• Replace the frayed belt.
• Adjust the pilot light
• Call the furnace service to adjust or clean the burners.

5. The oven light is off - start a pilot off

Possible causes

• The pilot can be turned off due to a strong air flow, a dirty hole or dirt in the gas pipe.
• The thermoconnector may also be defective and be cutting the gas flow.

Possible repairs

• For a general description of the pilot of a gas furnace and how to solve problems, repair and ignite it, please see gas oven pilot and thermoconnector. Also see the How to replace a thermoconnector tutorial.

6. Problems with electronic ignition of the oven

Furnace New furnaces do not depend on a permanent pilot to turn on the gas burners. Electronic ignition is typically performed in one of two ways:

• Indicator, or
• Hot surface ignition

The intermittent pilot system uses an electronically controlled high voltage electric spark to power the gas pilot and then the main burners when the thermostat calls for heat. In this situation, If you didn’t get solution, better to take help furnace repair in Burr Ridge, IL.

The hot surface ignition system uses an electronically controlled resistance similar to the filament of a light bulb (and shown in the photo above), to ignite the gas burner.

See the tutorial Overview and repair of the electronic ignition oven for troubleshooting and repair tips for electronic ignition furnaces.

7. Oven and thermostat do not match

Ovens and thermostats are not mixable appliances. Using the wrong type of thermostat with an oven can cause operation problems and can be dangerous. Although the thermostats look similar they are designed differently.

There are numerous types of heating systems and thermostat systems and need to be coordinated for safe and proper operation.

Review the thermostats and furnace compatibility tutorial to understand the three thermostat systems used today:

• Mill voltage
• low voltage
• Voltage online

8. Furnace problems caused by thermostats

Some common symptoms present in the oven may be due to a faulty thermostat. After you have confirmed that the oven is not the problem, check the thermostat.

Problems with the thermostat can be reflected in a furnace that does not produce heat, abrupt changes in temperature or turn on and off too often. As described in the previous section compatibility between the thermostat and the oven, you need to determine what type of thermostat you have for your oven.