Heating / March 12, 2019

3 Signs of Heat Exchanger Problems

Virtually all homes that contain central heating system contain a component known as the heat exchanger. As its name suggests, the heat exchanger transfers heat to the air of your home, while keeping toxic exhaust gases safely isolated. This central role makes the heat exchanger one of the most vital parts of a residential furnace system.

The punishing conditions inside of a heat exchanger mean that certain problems develop as time goes on. Unfortunately, many homeowners fail to recognize the signs that their heat exchanger has a problem. If you would like to learn how to troubleshoot problems with this component, keep reading.

1. Carbon Monoxide Alarms Going Off
   Virtually all gas-burning furnaces produce some quantity of carbon monoxide, a highly deadly gas. Under ideal operating conditions, this gas passes through the heat exchanger and moves safely out of your house through the flue. Yet if your heat exchanger has become cracked or corroded, carbon monoxide may escape into the air of your home.If the carbon monoxide alarms in your home have recently begun going off, you must contact an HVAC contractor immediately to inspect your heat exchanger. Of course, you should understand that other problems can also lead to elevated carbon monoxide levels. Water heaters, wood stoves, and fireplaces can all produce dangerous amounts of carbon monoxide.

   Homeowners should also understand the link between furnace efficiency and carbon monoxide. Simply put, a well-tuned furnace produces relatively small amounts of this dangerous gas. A furnace with an incorrect air-to-fuel ratio, on the other hand, may produce much greater amounts of carbon monoxide.
   Therefore, in addition to staying on top of any heat exchanger damage, you must have a trained technician regularly maintain your furnace.

2. Black Streaks on Your Furnace Filter
   All central HVAC systems contain a special filter used to keep contaminants from damaging or clogging the sensitive mechanisms inside of your furnace. This filter, commonly referred to as the furnace filter, resides in the return air duct. Air moving out of your home passes through this filter before it moves into the furnace system.As discussed above, a cracked or corroded heat exchanger allows carbon monoxide and other exhaust byproducts to escape into your home. One of these byproducts happens to be soot. Your furnace may not produce enough soot that you can visibly see it in your home’s air. Yet black streaks on your furnace filter provide a strong clue that your home’s air contains elevated soot levels.

   The presence of such soot generally indicates that your system has a leak somewhere — often in the heat exchanger. Elevated soot levels may also indicate that your furnace itself requires attention. Clogged burners, poor venting, and improper air-to-fuel ratios can all lead to excess amounts of soot.

3. Pooling Water
   Another strong clue that your heat exchanger may have developed a crack involves pools of water around your furnace. This problem occurs more frequently for those who own high-efficiency furnaces. A high-efficiency furnace actually contains two heat exchangers. The second exchanger allows the system to capture even more heat from your furnace’s exhaust.The second heat exchanger performs its job so well that any water vapor present in the exhaust often condenses. Under normal conditions, a special condensate line funnels this water to a nearby drain. If your heat exchanger has a crack or hole, condensate may begin escaping in places where it shouldn’t.

   Other issues such as clogged filters and blocked condensate lines can also lead to pooling water. To determine if your heat exchanger lies at fault, contact a professional as soon as possible. For more information about the state of your heat exchanger, contact San Diego’s experts at Mauzy Heating, Air & Solar.