Why is Your Furnace Leaking?

HVAC technician checking refrigerant levels with manifold gauges during AC repair.
Table of Contents

How to Fix a Leaking Furnace and Prevent Future Issues

“Help! My furnace is leaking. After mopping up the mess, I see another puddle starting to form, but I can’t tell where it’s coming from. Should I call HVAC experts to come to have a look? Or can I attempt a DIY approach to fix the leaking furnace myself?”

As the temperatures rise in Southern California, the last thing you want to deal with is the furnace leaking water in summer. Several issues may lead to a furnace leaking water, including loose valves, excessive pressure, or issues with the connecting pipes. We highly recommend contacting a reliable Thousand Oaks HVAC repair team to pinpoint the leak and remedy the problem. 

Why Is My Furnace Leaking Water?

Before discussing the solutions, it is crucial to figure out why your furnace is leaking water. Strange as it may sound, a gas furnace leaking water is an actual problem that could occur. Several issues can cause a leaking furnace.

Let’s discuss the causes of furnace leaks to help you better understand your furnace system and know when to call your local technician. The usual causes of furnace leaks include:

Causes of Furnace Water Leaks

1. Condensation Leak

Is your high-efficiency furnace leaking? You probably have a condensation leak to blame. 

High-efficiency furnaces (furnaces with an AFUE rating of either 90 or above) contain two heat exchangers that help them produce more heat and generate condensation.

The condensation caused by heat production must get carried out of your home via pipes leading to a floor drain. When these pipes break or get clogged, water starts to collect and pool up around the base of the furnace.

2. Humidifier Leak

Is your furnace leaking water in winter? Consider having your humidifier checked. A humidifier is linked to your plumbing system to add moisture to the air. Excess water in the humidifier empties through the drain line, so if it gets clogged or blocked, water will build up as it won’t drain as quickly as it should.

Contact our Thousand Oaks heating repair specialists if you need help with your leaky humidifier. You can also avoid such issues by scheduling preventative HVAC maintenance with our Conejo Valley HVAC experts.

3. Air Conditioner Leak

Is your furnace leaking water in summer only? 

In mild climates like California, your air conditioner and furnace work together to keep your home comfortable. When both units run simultaneously, the AC’s condensation pan might fill up and drip water onto the heating system, making it seem like your furnace is leaking.

4. A Clogged Filter

Did you know that a dirty or clogged AC filter can cause water leaks in a furnace if you have central air conditioning? A dirty air filter may restrict airflow through the furnace coil, resulting in excessive moisture and freezing temperatures that can cause ice to form outside the coil. When your A/C isn’t running, the ice will melt and leak into your furnace if the condensate drain can’t handle all the moisture.

Ensure that you always check the condition of your furnace’s air filter and replace it if it’s dirty. Regularly changing your air filter will also ensure that you don’t deal with a furnace leaking carbon monoxide. 

5. A Plumbing Leak

Is your furnace leaking water when AC is off? Sometimes, there might be an issue with the plumbing, not the furnace itself. A leak in your roof or plumbing might drip water onto your furnace and make it seem like you have a leaking furnace.

6. Heat Exchanger Problem

Still haven’t found the source of the leak? An issue with the heat exchanger in your furnace might be causing the water leak. Find a Conejo Valley HVAC repair near me and call 805-499-0448 today! 

Is Furnace Leaking Water Dangerous?

While a leaking furnace may not pose an immediate threat to your safety, it sure puts your comfort on the line. If you leave your leaking furnace unfixed, you will soon be facing some costly outcomes as water is destructive.

Leaking water can lead to rust developing on the working parts of your furnace. Initially, this leads to increasing inefficiency and eventually to breakdowns and costly repairs.

How to Fix a Leaking Furnace

Immediately you notice that your furnace is leaking water, you need to turn it off instantly and call a reputable HVAC company to help you repair it. Here are the steps you should take as you wait for help to arrive: 

  • Turn off your furnace – The first thing you should do is switch off the entire heating system
  • Adjust the thermostat to OFF, then close the gas line valve – Set the thermostat to off, then shut off the gas line valve and the electrical breakers associated with your furnace.
  • Dry off the water – Mop up all the water collected around your furnace, as standing water is not good for your furnace and your laminate flooring. 
  • Wait for expert HVAC repair near me – Besides looking for the leak, our professional Thousand Oaks HVAC technicians will inspect the humidifier, air conditioner, and any other component affecting the leak.

Contact Conejo Valley Home Services in Newbury Park for all your heating and furnace needs, including installations, repairs, and preventative maintenance. 

How to Prevent Your Furnace from Leaking Water

Don’t want to deal with a gas furnace leaking water? Consider scheduling regular furnace preventative maintenance with Conejo Valley Home Services. Our able technicians will find minor furnace issues and deal with them promptly before they escalate into more significant problems. 

Hire Professional Furnace Repair Services

Unless you have the skills and certification, or the solution is simple, like replacing an air filter, never attempt to fix a leaking furnace on your own. You’ll likely end up causing more damage and paying massive amounts for HVAC repairs and replacements.

If you spot a leak, do not deal with it alone. Let Conejo Valley Home Services help! Call us today at  (805) 499-0448.

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