Why Is My Furnace Leaking Water in Winter? | Causes of Furnace Leak
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Why Is My Furnace Leaking Water in Winter?

Unfortunately, leaks are a part of life. While a puddle beneath your air conditioner may not make you think twice, water leaking from your furnace should definitely be cause for alarm.

We’ve put together this guide to help you understand what’s causing your leak, and what you can do to protect your home’s heating equipment.

Possible Causes of a Furnace Leak

A conventional furnace, otherwise known as a standard-efficiency furnace, does not produce condensation. On the other hand, a high-efficiency furnace, or a condensing furnace, has a second heat exchanger that produces condensation. Once this water vapor is created, it drains out through a PVC pipe into a condensate pump or floor drain.

If this system isn’t working properly, you’re likely to experience a leak. Here are some of the most common issues that cause your condensate drainage system to leak:

  • Clogged condensate drain hose
  • Cracked inducer assembly
  • Damaged condensate drain line
  • Clogged condensate trap
  • Backed-up condensate pump

If you don’t have a high-efficiency furnace, the leak is likely coming from another appliance, like an air conditioner, water heater, or humidifier.

An easy way to tell the difference between a standard and high-efficiency model is by looking at the flue pipe on the furnace. A standard model will usually have a metal pipe and a high-efficiency model will have a PVC pipe.

How to Protect Your Furnace

Once you notice your furnace is leaking, it’s important to take the proper steps to prevent water damage from affecting your heating system.

  1. Turn Off Your Furnace

  2. Before you do anything else, turn off your furnace to prevent more water from leaking out. You can turn your furnace off by switching the dial on your thermostat. Otherwise, you can flip the switch on the side of your furnace.

  3. Clean Up Pooled Water

    Once you’ve turned your furnace off, mop up any water that’s pooled onto the floor. If there is any water that’s spread to electrical outlets or other appliances, take extreme caution to avoid the risk of electric shock. Pause your clean-up until you’ve turned off the power at your circuit breaker. Better yet, call an experienced electrician for assistance.

  4. Call an HVAC Specialist

    After you’ve safely cleaned up the pooled water, call a professional HVAC specialist for repair service. An HVAC technician will be able to diagnose what’s causing the leak in your furnace and make recommendations for repair. The good news is that a repair job for this kind of leak generally involves just a few small parts. As long as your furnace was not water damaged in the process, you likely won’t need a full furnace replacement.

Schedule Furnace Repair in Bend, OR

If your furnace is leaking, count on the experts at Ponderosa Heating & Cooling, Plumbing & Electrical. Our experienced HVAC technicians have the tools to quickly diagnose and repair your furnace so you can return to enjoying the comfort of your home. We’re the top choice for furnace repairs in Bend, OR, and the surrounding Central Oregon areas.

Call us today at 541-549-1605 to schedule heating service.

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