Troubleshooting Common Furnace Problems

03 Jan Troubleshooting Common Furnace Problems

Kingsport, TN

Few home issues are as inconvenient as problems with the furnace because furnace problems are almost never noticed until the furnace is actually in operation. This, in turn, invariably means that it is in the fall or winter when it is cold out, and if the problem with the furnace is that it is not producing heat, homeowners can confront the nightmare scenario of pipes freezing and bursting if it is cold enough outside.

While it is never a bad idea to call in a professional, there are some furnace problems that can actually be repaired at home and fairly quickly. However, this requires some know-how, such as being able to figure out what the problem is and whether it can be repaired at home. While lots of things can go wrong with a furnace, there are a few very common problems which, once identified, can narrow the decision as to whether to attempt a home repair or call in a maintenance technician. What are some of these?

Furnace is blowing cold air

A furnace that is working – in that it is blowing air but not warm air – is a situation that might be caused by a number of things that can be fixed at home.

These can include:

• Thermostat settings – It might very well be that the thermostat is not set correctly. If it is not set for “warm” but instead set for “on”, the thermostat is telling the furnace to produce air, but not necessarily warm air. Setting the thermostat to “heat” or “automatic” might solve this problem. Alternatively, the thermostat may have gone bad. This can be replaced by people who have a decent knowledge of electricity and the equipment to be used, but since a thermostat is a relatively inexpensive and easy fix, a technician would likely be a better option.
• Bad air filter – Another issue might be a clogged or dirty filter. A bad filter may restrict airflow into the furnace, which would cause it to overheat. Many furnaces have safety mechanisms that will shut off the heat to prevent damage to the furnace. Therefore, a change of filter might solve the issue.
• Duct work – Sometimes, the air coming into the furnace might be just fine, but there may be a difficulty with the air coming out of it. Ducts that leak or have connection problems, may cause the warm air to leak out. However, unless the problem in the ducts is obvious, this will likely require a visit from a technician.
• Pilot light – In nearly all furnaces, air is heated by the burning of fuel. The fuel is ignited by a pilot light, which is supposed to stay on permanently. On occasion, a pilot light goes out and, in an older furnace, can be relit to restore heat. However, newer models have an electric ignition, and if the pilot light is out, the ignition is faulty. This will require a visit from a technician.

Furnace is not on at all

There are a host of reasons why a furnace will simply not come on at all, but some of them can be taken care of without a technician. One of them may be as simple as the unit not getting electricity because the switch has been flipped at the breaker. Turning it back on again may solve the problem, though if the switch keeps tripping, a technician may need to be called.

It might also be that the access panel on the furnace is open. Since this is extremely dangerous, a furnace will not operate if the panel is open. Closing it should resolve the issue.

Otherwise, some of the same causes for the furnace not producing heat may mean it will not come on at all; namely, a clogged filter or incorrectly set (or failing) thermostat may prevent the furnace from blowing any kind of air, hot or cold. If all the possible causes mentioned have been checked and fixing them does not solve the issue, a visit from a technician is probably in order.

Bad smell

If the furnace comes on and does not produce heat but produces an unpleasant chemical smell reminiscent of formaldehyde, the issue is likely with the heat exchanger. This can be verified by looking at the furnace itself: if there is water leaking around it, if it has soot, and if the flames in it are not blue but instead yellow or orange, the heat exchanger is almost certainly malfunctioning. This will certainly require professional repair, as a poor heat exchanger can cause a carbon monoxide leak into the house, leading to a variety of health issues.

Noise

A furnace which is making unusual noises can have several causes, and determining which is which largely depends on the noise itself. A high-pitched whining noise is probably caused by a loosened or worn-out blower belt, which can be repaired at home by those who are mechanically inclined. On the other hand, a loud scraping noise may be caused by worn-out blower-ball bearings or by a faulty blower wheel, which needs replacement and is probably something to be left to professionals. Finally, a loud bang when it’s turning on may indicate a buildup of dirt or problems with the igniter, which will likely also best be left to professionals.

For those whose furnaces have begun to have problems in the Tri-Cities, Thompson Electrical Services offers a full range of repair or replacement options which they have been providing for close to two decades. To set up an appointment, call (423) 343-5726 or use the website to get a quote.