BUD MATTHEWS SERVICES IS OPEN AND READY TO SERVE. We recognize our services are often emergency in nature, and we remain fully committed to fulfilling the needs of our community. Learn more here!
Serving the Chapel Hill Area for Over 40 Years!

Why Is My Furnace Leaking Water?

Posted on: February 4, 2019

If you’re asking this question, you’re probably a bit confused. After all, furnaces don’t use water to run, do they? A boiler uses water, but a furnace heats up air with either gas burners or electric heating elements, and then sends the air into the ducts.

And yet, there is it: water leaking out of the furnace cabinet onto the floor. What’s happening? And does it mean you need heating repair in Chapel Hill, NC for your HVAC system?

We’ll take a closer look into this apparently odd, but actually common, heating problem.

High Efficiency Furnace Condensation

Although a furnace doesn’t use water to run, special high efficiency furnace produces condensation during combustion. This is because a high-efficiency furnace collects vapor in the heat exchanger from the cooled-off combustion gas rather than venting the gases out a flue. This vapor moves to a second heat exchanger, were it’s condensed to release further heat. It’s this second combustion chamber that allows high-efficiency furnaces can produce more heat energy from their fuel. The furnace then vents the vapor out of the system.

If there are clogs in the condensation tubing, or breaks in the tubing, it can lead to the condensation escaping onto the floor. You’ll want this repaired as soon as possible. Another possibility is a faulty second heat exchanger. Damage to the heat exchanger is usually serious enough to warrant having the furnace replaced.

Poor Venting in a Mid-Efficiency Furnace

A mid-efficiency furnace (lower than 90% AFUE) shouldn’t develop condensation because the vapor from the heat exchanger is vented out directly through a metal flue pipe. (High-efficiency furnaces use PVC pipes for flues.) However, this flue pipe must be correctly sized, or else the vapor will start to cool down in the pipe and create condensation that then leaks down out of the furnace. Poor venting is a major problem that needs to be addressed right away. (If you always arrange for furnace installation with licensed professionals, you shouldn’t run into this issue.)

The Air Conditioner Is at Fault

The standard HVAC configuration in homes is a combination of a furnace and air conditioner in a single cabinet, where they share the same blower fan. The air conditioner is housed over the furnace. If the air conditioner has a clogged condensate drain, water from the condensate pan will start to overflow and spill out into the cabinet. It may look like the furnace is leaking, but it’s actually the air conditioner.

This is still something that needs professional repair ASAP. Water dripping onto the furnace can create corrosion, and corrosion puts the furnace in danger of cracks along the heat exchanger, a potentially hazardous condition. You also want this fixed so the AC can work correctly.

Remember, no matter what is causing water leaks from the HVAC cabinet, water damage is expensive to remediate and can create mold and mildew growth. You never want any leaks from your HVAC system! Let our expert technicians track down the source of the leak and have it fixed or help you arrange for a system replacement if the damage is bad enough.

Call on Bud Matthews Services for all your home services needs in Durham, NC.

See What Your Neighbors Are Saying

“Many heartfelt thanks to the people I talked with on the phone late this afternoon who were concerned enough to send Pat over to check on our frozen pipes and dripping shower. Pat was so kind and professional and fixed...”

– Rindi

“Bud, I want to send my thanks to your company and especially to Scott. He got into more than he bargained for on our project yesterday. He went out and got different parts and went the extra mile to make...”

– Dave W.

“They were professional, honest, and cleaned-up after their work, and even took the shop-vacuum around the living room for good measure (we have a GSD - say no more)! Nice folks.”

– Judith A. – Pittsboro, NC

“Bud Mathew responded to our call even though it was made during the weekend. Plumber came to the house, identified the problem, gave us a temporary fix and suggested we wait until Monday to fix it. (That saved us some...”

– Gloria C. – Carrboro, NC

“They replaced a number of parts in my old Maytag dryer. It has been very reliable for 26 years and I want to keep it rather than buy a new one. Works great now!”

– Jane S. – Chapel Hill, NC

“Repair people were punctual and cordial. They troubleshot a problem, trying different approaches when the first try didn't work to clear the line. They explained everything they were doing as they did it while we watched. They were very efficient...”

– Diana B. – Efland, NC

“We were very happy with the process and outcome. Noah was very responsive. If he couldn't answer his phone when I called, he quickly returned calls. Everyone was very polite and respectful. They did a great job. Noah made good...”

– Jeffrey H. – Durham, NC

“They fixed my LG Front Load Washing Machine, which was leaking. They also helped me level it properly. They were on time, they provided clear estimates, they were professional, and they clearly explained every step of the process to me...”

– Lindsey S. – Chapel Hill, NC
See More Reviews
Certifications & Affiliations

We recognize that our services are of a special and often emergency nature, and we remain fully committed to fulfilling the needs of our community even as potential demand for our services may increase with more families either choosing to or being required to remain home for extended periods of time. More importantly, the safety of our employees and customers is always our highest priority, and we recognize that heightened diligence and focus on health and safety is required during these challenging times. We are actively monitoring updates from the CDC, WHO and local health officials; and we have been proactively and continually implementing measures and developing plans to prioritize the health and well-being of our employees and customers. Including:

  • Equipping all technicians with masks, gloves, and disinfectants.
  • Social distancing – Avoid handshakes and limit direct contact with customers during their visit.
  • Requiring technicians to clean all surfaces with disinfectants before and after performing work.
  • Requiring all employees to stay home if they are experiencing symptoms such as shortness of breath, coughing or fever.