What To Do If Your Furnace Is Leaking Water in Summer

There are some things you only think about during certain times of the year. When was the last time you thought about whether you were wearing sunblock in the middle of winter? Conversely, when was the last time you thought about having a cup of hot chocolate during one of Sacramento’s many triple-digit summer heat waves?

You probably don’t tend to do either of those things all that often, do you? And, I’m just guessing here, but you probably also don’t think about your furnace much during the middle of summer—if all is going well, that is. I guess that’s why I get a panicked phone call from time to time from folks who want to know what to do about their furnace leaking water in summer.

So, that’s what I’d like to talk about here today: what to do if you’re one of those folks who notice that their furnace is sweating buckets—just like you—in this extreme heat.

The First Thing You Should Do If Your Furnace Is Leaking in Summer

Before I jump into the many reasons why your furnace is leaking during the warmer months of summer, I’ll start by saying that the first thing you should do if you notice a pool of moisture around your furnace is to clean it up. While you’re probably thinking that I really don’t need to tell you this, you’d be surprised to know how many folks get caught in a tizzy once they notice the water and forget to mop it up. It’s only a matter of time before that pool of water starts to smell musty, cause damage to your floor, or start to grow mold—and it’s a bit of a safety hazard. Slip ’N Slides are for outside, so mop up that indoor puddle as soon as you notice it.

Why Your Furnace Is Leaking in Summer

Now that you’ve mopped up the mess, let’s get into what caused it in the first place. First, you should understand that your AC produces a whole lot of water in the form of condensation during the hot summer months. If your unit is working properly, you should never see this water, but you may indeed hear a faint dripping from time to time, which is normal. The water will drip into the drain line and then be channeled into the floor drain. 

If something isn’t working properly, though, water can leak out and make it appear that something is going wrong with your furnace when actually the problem is typically with the AC unit.

Here are a few of the reasons why you may see water under your furnace in the summer months:

• The drain is clogged: A clogged drain is probably the most common reason why your furnace appears to be leaking in the summer months. Sometimes the AC and the furnace share an internal drain, and if there’s something plugging up the drain, which can happen if dirt and dust collect in there, the condensation your HVAC system produces inevitably overflows and leaks onto the floor under the furnace. In this case, it isn’t actually your furnace leaking, it just appears to be. If you’ve had your HVAC serviced lately, this is likely not the problem, but an HVAC pro will be able to rule it out. They’ve got the tools to get in there are see if there’s a clog or not.
• Your drain pan is full: Just below the evaporator coil in your furnace or air conditioner is a drain pan that catches the condensation coming off the coil. If you’ve got an old unit, your drain pan might be rusted or damaged, which could mean that the water is running right through it and dripping onto the floor instead of into the drain pipe. If this is the case, you’ll need a pro to replace your drain pan with a shiny new one.
• Your air filter is dirty: This seems to be a likely culprit behind many HVAC problems but that is because a clean filter is so essential to a smoothly running machine. If your air filter is dirty, ice will form on the evaporator coils. This ice eventually melts and often creates too much of a puddle for the drain pan to contain, resulting in a bit of a flood. If you haven’t had your air filter changed in the last few months, this could be the problem behind the puddle.
• The condensate pump is faulty: For those of you who have your AC and furnace installed in your basement, then you have a condensate pump that works hard to push all of the accumulated moisture outside. If there’s something wrong with the pump, water doesn’t make it outside and instead accumulates on the floor, often under your furnace, again making it appear like it’s the source of the leak. If this is the case, a pro will be able to fix or replace your pump so that you won’t have any more leakage.

This Is Not a Summer DIY: Call a Pro to Fix Your Furnace Leak

Unless you’re an HVAC expert, it’s next to impossible to know which one of these problems is causing the furnace leak. The thing is, regardless of which one does turn out to be the culprit, a leaking HVAC or furnace is always cause for concern and could be a sign of something seriously wrong with your system. That’s why I’d recommend calling in the HVAC pros, like the friendly folks at Bell Brothers, as soon as you finish mopping up the mess so that they can diagnose and fix the problem as quickly as possible.

The thing is, regardless of which one does turn out to be the culprit, a leaking HVAC or furnace is always cause for concern and could be a sign of something seriously wrong with your system.

While you have the pros at your place, it’s also a good idea to schedule regular HVAC and furnace maintenance with them. Not only can regular maintenance prevent problems with your system, it also keeps your furnace and air conditioner spick and span and running as efficiently as possible. What’s also great is that maintenance checks and tune-ups can increase the lifespan of your heating and cooling units. That means you won’t have to worry about forking out the cash for a new one every ten years.

Remember, if you do experience a leak under your furnace this summer, don’t sweat it. Just keep in mind that the sooner you call a pro, the sooner you can go back to enjoying your peaceful, cool home. If you leave it too long, though, bigger issues could develop with your unit and you could be without a furnace—and an air conditioner. And in this Sacramento summer heat, I wouldn’t wish that on anyone.

At Bell Brothers, our trained HVAC professionals would love to help you keep your AC running smoothly all summer long by scheduling regular HVAC maintenance. Contact us today to schedule a free in-home consultation.

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Image courtesy Stasique