Furnace Leaking Water in Winter: Steps to Take

Premier Systems
December 5, 2022

The winter is when we depend on our furnaces the most. Unfortunately, during the winter, your furnace becomes more susceptible to breaking down. A furnace leaking water in winter generally indicates a bigger problem.


Sometimes this problem is an easy fix, but other times the solution can be more complicated. This guide explores what to do with a leaky furnace, including when to call for a furnace repair by Premier Systems


Do You Have a Conventional or Condensing Furnace? 

Before diagnosing what caused the leak and implementing the right repair solution, you'll need to check what kind of furnace you have. 


It's easy to tell if you have a conventional furnace if you can spot a metal exhaust. Another way you can tell is if it has an Annual Fuel Utilization (AFUE) rating at or below 90 or if there isn't an AFUE rating listed. 


If your furnace has a PVC exhaust pipe or an AFUE rating above 90, then it's a condensing furnace. A conventional furnace leaking water in winter is never a good sign and requires a call to an HVAC professional. 


What Are the Main Causes of Furnace Water Leaks? 

Knowing how to repair a leaky furnace starts with accurately diagnosing the problem. For example, it's normal for a high-efficiency furnace to produce condensation, which usually isn't an issue. However, your furnace may have a broken part: 


Problem with Your Humidifier

AC units have a dehumidifier, while furnaces often have a humidifier. A humidifier's primary purpose is to add moisture to the air. This added moisture results in more trapped heat, warming your home more efficiently during the colder months. 


Not every furnace has a humidifier, however. You can quickly tell if your furnace has a humidifier by seeing if it has a box with several pipes and wires running toward your furnace. 


Sometimes a humidifier can cause your furnace to leak, usually because you have a clogged or dirty filter. You only need to clean or replace the filter to resolve this problem. 


Your humidifier's drain can also be clogged, meaning you'll need to clean it. While a clogged drain or filter is usually an easy fix, it's crucial never to ignore a leak. Even a minor leak can escalate into a bigger issue that may require extensive repairs. 


Condensate Pump 

Not every furnace has a condensate pump, and this is an issue that only pops up in condensing furnaces. These furnaces feature condensate pumps designed to push created condensation inside the furnace out to pipes. 


A malfunctioning condensate pump can trigger water backups, resulting in a leak. It's not advisable to attempt a condensate pump repair yourself. Instead, it's better to call a professional HVAC crew. 


Flue Pipe

An ill-fitting flue pipe can often trigger a leak, requiring immediate repairs. Your heat exchanger can create condensation, and your flue pipe is responsible for draining this condensation. However, an improperly installed flue pipe can cause a water leak. 


If you have a leaky conventional furnace, you should look at your flue pipe before anywhere else. However, the issue can also be your drainpipe. 


Conventional furnaces don't produce condensation within their unit. Instead, they use a drainpipe to remove gases outside, creating condensation. Like with a flue pipe, an ill-fitted drainpipe can cause a leak. 


Secondary Heat Exchanger

A furnace leaking water in winter can also be due to your secondary heat exchanger. A secondary heat exchanger absorbs your primary heat exchanger's combustion exhaust. Your furnace then releases excessive heat, producing water vapor. 


Look for the following signs to check if your secondary heat exchanger is damaged: 


  • You can spot water dripping from the fan compartment.
  • You can see some visible cracks.
  • You notice corrosion on your secondary heat exchanger.


Unfortunately, a damaged secondary heat exchanger can often mean your furnace is reaching the end of its lifespan. It's possible to repair a furnace with this problem, but usually, it's cheaper to replace it with a new energy-efficient model. 


What Should Homeowners Do If Their Furnace Starts Leaking During Winter?

Whether you're dealing with a minor or a substantial leak, taking immediate action is vital. Here are the following steps to take when dealing with a furnace leaking water in winter: 


  • Turn off your furnace's power: Many furnaces have a switch you can flip to turn off your furnace quickly. However, if you cannot spot one, you can turn your system off using the breaker. 
  • Clean up any water around the unit: Start by soaking up all the water around your unit using a dry towel. However, you may need to use a wet-dry vacuum for large water amounts. 
  • Try diagnosing the issue: Try diagnosing the issue before calling a professional HVAC team. If you have a dirty or clogged air filter, replace it with a new one to see if that resolves the problem. 
  • Call a professional HVAC team: Lastly, you'll want to call a professional HVAC team. The right team will bring years of experience and can quickly resolve any leak you may have. 


Can You Repair a Leak Yourself or Hire an Amateur? 

Some homeowners see an issue like a leaking furnace as a chance to try out their DIY skills. However, you shouldn't try repairing a furnace yourself for the following reasons: 


You May Not Have the Right Tools 

A professional HVAC team brings the right tools to repair and install furnaces. However, you may need to buy new tools before repairing your furnace or spend much more time with the obsolete tools you have.

 

You Can Cause Further Damage 

You can end up damaging your furnace when attempting to repair it. Even if you fix the initial leak, you can create the right conditions for parts to break down in the future. A professional HVAC team can avoid this problem. 


You Can Void Your Warranty 

Many furnaces have a warranty that can save you money in the long run. However, these warranties generally have some restrictions. One typical limitation is that you can't have an unprofessional service your furnace. 


Likewise, if you use a service from an unlicensed maintenance team, you may not be covered if they damage your furnace. 


How Often Should You Service Your Furnace? 

Some homeowners only call a repair team when they notice issues with their furnaces. Besides a leak, other issues can include: 


  • A furnace blowing cold air 
  • A furnace not turning on or short-cycling 
  • A furnace being abnormally loud
  • Having broken down parts 
  • Suddenly having skyrocketing energy bills 


The best way to solve these problems is through preventative measures. Servicing your furnace at least once a year can catch and fix minor issues before they become major headaches. It's best to service your furnace right before winter. 


For the Best Furnace Repair Services, Call Us Today 

Furnaces can make your home and family comfortable, especially during winter. Besides keeping you warm, a furnace can also improve indoor air quality and overall comfortability. 


However, a furnace leaking water in winter can quickly become a nightmare. When faced with this issue, homeowners can call Premier Systems for the best furnace repair and maintenance services. 


Even if your system has a minor leak, calling HVAC technicians is essential. When you call us, we don't waste any time coming to you with tools in hand, ready to diagnose and fix the leak. With routine maintenance, we can help prevent leaks from occurring again.


Bozeman, MT, residents can call our team today at 406-333-0177 for the best furnace maintenance contractors!

June 1, 2026
5 HVAC Problems Homeowners Notice During Montana's Rainy Days Rainy weather can be a welcome break from the summer heat, but it can also reveal hidden issues with your home's heating and cooling system. Increased humidity, fluctuating temperatures, and excess moisture can all impact your HVAC system's performance. If you've noticed your home feeling less comfortable during rainy weather, your HVAC system may be trying to tell you something. Here are five common HVAC problems homeowners experience during Montana's rainy days and what you can do about them. 1. Excess Indoor Humidity One of the most common complaints during rainy weather is a home that feels damp or sticky, even with the air conditioner running. Your HVAC system does more than cool the air—it also removes moisture. If your system isn't properly dehumidifying your home, indoor humidity levels can rise quickly. Signs of High Indoor Humidity: Sticky or clammy indoor air Condensation on windows Musty odors Increased allergy symptoms If your home consistently feels humid, your air conditioner may need maintenance or your system may be improperly sized for your home. 2. Musty Smells Coming from Vents Rain and humidity create the perfect environment for mold and mildew growth. If you notice a musty odor when your HVAC system turns on, moisture may be collecting somewhere in the system. Common causes include: Dirty evaporator coils Clogged condensate drains Mold growth in ductwork Excess moisture around the air handler Ignoring these odors can lead to reduced indoor air quality and potential health concerns for your family. 3. Reduced Airflow Rainy weather can expose airflow issues that may have gone unnoticed during drier conditions. Dirty air filters, clogged coils, or ductwork problems can restrict airflow and make it harder for your system to maintain comfortable temperatures. Watch for: Weak airflow from vents Rooms that won't cool evenly Longer run times Higher energy bills A professional HVAC inspection can quickly identify and resolve airflow problems before they become major repairs. 4. Water Leaks Around Your HVAC Equipment Many homeowners are surprised to find water pooling near their indoor HVAC unit during rainy periods. While it may seem like rainwater is entering the system, the issue is often related to a clogged condensate drain line. Your air conditioner removes moisture from the air, and that water needs somewhere to go. When drain lines become blocked, water can back up and leak around your equipment. Don't ignore water around your HVAC system. Left untreated, it can damage flooring, walls, and even the unit itself. 5. Thermostat and Electrical Issues Heavy rainstorms can sometimes cause power fluctuations that affect HVAC controls. If your thermostat isn't responding properly or your system cycles on and off unexpectedly after a storm, electrical components may have been affected. Common warning signs include: Blank thermostat screens Inconsistent temperatures System short cycling Failure to start If you notice these symptoms after severe weather, it's best to have a technician inspect the system to prevent further damage. Keep Your HVAC System Ready for Any Weather Montana's weather can change quickly, and your HVAC system needs to be ready for everything from summer rainstorms to humid days and temperature swings. Regular maintenance helps identify small problems before they become expensive repairs. A seasonal HVAC tune-up can: Improve system efficiency Reduce humidity issues Prevent unexpected breakdowns Extend equipment life Improve indoor air quality Schedule Your HVAC Inspection Today If you've noticed musty odors, humidity problems, weak airflow, or water leaks during recent rainy weather, don't wait for the problem to get worse. Our experienced technicians can diagnose the issue and help keep your home comfortable no matter what the forecast brings. Contact us today to schedule your HVAC inspection and ensure your system is ready for Montana's changing weather.
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Wildfire season has become an increasingly common part of life in Southwest Montana, especially for homeowners in Bozeman, Belgrade, and Four Corners. While the smoky haze outside is easy to see, what’s happening inside your home is often less obvious. Many people assume that simply closing windows and doors will keep them safe—but wildfire smoke can still enter your home and impact your indoor air quality (IAQ) in ways that affect both comfort and health. Why Wildfire Smoke Indoors Is a Serious IAQ Concern Wildfire smoke is made up of extremely fine particles called PM2.5, which are small enough to pass through tiny openings and even some standard HVAC filters. Once inside your home, these particles can circulate through your ductwork and linger in the air. For homeowners in our area, poor indoor air quality during wildfire season can lead to: Coughing, sneezing, and throat irritation Headaches and fatigue Aggravated asthma or allergies Increased strain on your HVAC system Without proper filtration and system maintenance, your home’s air may not be as clean as you think. How Smoke Affects Your HVAC System Your HVAC system plays a major role in managing your indoor air quality —especially during wildfire events. When smoke enters your home, your system can either help remove harmful particles or unintentionally spread them throughout your space. If your system isn’t equipped with the right components, you may experience: Reduced filtration of fine smoke particles Dirty ductwork circulating contaminants Increased wear and tear on system components Decreased efficiency and airflow This is why homeowners across Bozeman and Belgrade are upgrading their systems to better handle wildfire smoke conditions. HVAC Solutions to Improve Indoor Air Quality During Wildfire Season The most effective way to protect your home’s air is through professional HVAC solutions designed specifically for indoor air quality in Four Corners, Belgrade, and Bozeman. Upgrade to HEPA or High-Efficiency Filters Standard filters aren’t designed to capture the smallest smoke particles. Upgrading to HEPA filters or high-MERV rated filters allows your system to trap significantly more airborne contaminants, improving your IAQ immediately. Install Whole-Home Air Purification Systems Advanced air purification systems integrate directly into your HVAC system to continuously clean the air as it circulates. These systems are especially effective during wildfire season when outdoor air quality is poor for extended periods. Add an Air Scrubber Air scrubbers go beyond traditional filtration by actively removing pollutants, odors, and particles from the air and surfaces in your home. This added layer of protection can make a noticeable difference in homes affected by wildfire smoke. Schedule Professional Duct Cleaning If smoke has entered your home, particles can settle inside your ductwork. Duct cleaning removes built-up contaminants and prevents them from being recirculated, helping restore cleaner air throughout your home. Keep Up with HVAC Tune-Ups Regular HVAC tune-ups ensure your system is running efficiently and filtering air properly. During wildfire season, a well-maintained system is critical for maintaining healthy indoor air quality. Long-Term Protection for Homes in Bozeman, Belgrade & Four Corners Wildfire smoke isn’t just a temporary inconvenience—it’s an ongoing challenge for homeowners in Southwest Montana. Investing in indoor air quality solutions through your HVAC system provides long-term protection for your home and your family. By combining: High-efficiency filtration Whole-home air purification Air scrubbers Clean ductwork Routine system maintenance …you can significantly reduce the impact of wildfire smoke indoors. Breathe Easier with the Right HVAC Support Your home should be a place where you can escape poor outdoor air—not bring it inside. With the right HVAC upgrades and maintenance, you can take control of your indoor air quality in Bozeman, Belgrade, and Four Corners, even during the peak of wildfire season. If you’re noticing smoke lingering in your home or want to prepare ahead of time, working with a trusted HVAC professional can help you choose the best solutions for cleaner, healthier air. Cleaner indoor air starts with the right system—and the right team behind it.
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