Why Is My Furnace Leaking?: 4 Reasons Your Gas Furnace Is Leaking Water

Have you ever checked on your furnace only to discover your feet are soaking wet? When water pools around the base of your furnace, there could be several explanations. Before you attempt to remedy the problem yourself, it’s best to call your local HVAC technician to properly diagnose the leaky furnace.

Below is a list of reasons why your furnace may be leaking.

Furnace Condensation Leak

Condensation is the most likely cause of leaks in high-efficiency gas furnaces. When the heat exchanger extracts heat over a long period of time, the combustion gases cool to create condensation. Normally, the moisture from the condensation is channeled into a floor drain, so if you notice a leak, it could mean one of three things:

  1. The condensation tubing is clogged.
  2. There are breaks in the line.
  3. The floor drain is clogged.

How do you know if you have a high-efficiency furnace? Furnaces with an Annual Fuel Utilization Efficiency (AFUE) rating of 90 percent or more are high efficiency. High-efficiency furnaces also have a white PVC vent pipe; standard efficiency furnaces have a metal vent pipe.

It is very unusual for a standard efficiency furnace to experience condensation leaks. If this is the case, then the flue pipe may not be the correct size.

Damaged Secondary Heat Exchanger

The secondary heat exchanger may be faulty if you’ve ruled out a condensation leak. Unfortunately, this problem is very expensive to repair, and most homeowners choose to replace the entire furnace. Remember, if the cost of the repair is more than half the the unit’s value, it’s best to replace the furnace altogether.

Interior Drain System Plug

If your air conditioner shares an internal drain with your heating unit, there may be an internal drain system clog that is forcing water into your furnace. It’s important to contact your local HVAC professional to unclog the drain to avoid any further damage.

Humidifier Leak

Whole-home humidifiers that are attached to the furnace may develop wear over time and leak into the furnace. If you schedule regular maintenance for your unit, then the heating and cooling contractor should have informed you of the issue before it became a larger problem. If you do not have your furnace tuned up regularly, schedule an appointment today. If the humidifier is leaking into your furnace, it can cause serious internal damage that will be very costly to repair down the road.

Leaky furnaces can not only damage the unit, but they can harm floors and walls as well as provide the optimal environment for mold to grow. To protect your health and home, please do not ignore the problem. The HVAC experts at Lenz Heating & Cooling proudly serve the Des Moines Metro Area and Waukee. Call us today for a free diagnosis or second opinion.