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My Furnace is Leaking Water – What Do I Do?

Water leaks in your home are frustrating, time-consuming, and can cause costly damage – not to mention costly repairs.

But what do you do when it’s your furnace leaking water? It’s easy for panic to set in – especially as the temperatures get colder and colder.

Here’s what you need to do if you find yourself in this situation.

Turn off Your Furnace and Call GLT for Repairs

If you discover your furnace leaking water, the first thing you should do is turn it off.

Make sure your thermostat is first set to ‘Off. Then turn the shut-off valve located on the gas line connected to your furnace and the electrical breakers associated with your furnace.

It’s likely that the problem causing the leak is something only professional repair technicians should handle, so your next step is to call us.

You should then mop up all the water that has collected around the base of your furnace. Standing water is bad for your furnace and your floor. Remember: Only do this if your furnace electrical circuit is shut off.

If your furnace looks like a lonely island in the middle of a small pond, it’s possible to rent a wet/dry vacuum from big hardware stores to make cleanup easier.

Why is My Furnace Leaking Water in the First Place?

Depending on whether you have a high-efficiency furnace (an AFUE rating of 90 or more) or a conventional furnace, a number of different things will cause your furnace to leak.

1. High-Efficiency: There’s a Leak or a Clog in the Condensate Lines

High-efficiency furnaces create condensation through the heat exchange process. When operating normally, this condensation is drained safely out and away from your furnace through the condensate line and drain trap.

If there’s a leak or a clog in the condensate lines, you’ll quickly find a puddle around your furnace.

2. High-Efficiency: Your Condensate Pump Isn’t Working

A condensate pump is what actually pushes the water through the lines and away from your furnace. These can experience mechanical problems which often cause leaks.

3. Conventional: The Metal Vent Pipe is Creating Condensation

If you’re furnace has an AFUE rating of less than 90, it’ll have a metal exhaust vent pipe (vs. the white PVC vent pipe of a high-efficiency furnace). The exhaust vent carries away the gases produced during the combustion process, and releases them outside while they’re still hot.

If this venting pipe isn’t properly sized for your furnace, gasses can get trapped by the extra air. Eventually they cool down – this forms condensation which leaks out of your furnace.

4. For Any Furnace: The Humidifier is Leaking

Many homeowners choose to add a humidifier to their heating systems to make their homes more comfortable during the dry winter months.

They have water constantly moving through them, and if they spring a leak or become clogged, it looks like it’s your furnace that’s leaking water.

This is something our technicians will thoroughly inspect when diagnosing the source of the water. It’s also something we can inspect when you have your annual furnace tune up.

5. For Any Furnace: It Might Actually Be the Air Conditioner

If we’re in that seasonal grey period where you use your air conditioner one day, and turn on the heat the next, it may not be your furnace leaking water.

Air conditioners absorb a lot of moisture from the air inside your home, so they also have condensate lines and a drain pan. If there’s a clog or leak, it could appear as though your furnace is the source.

Make Sure to Replace Your Furnace Filter

As a rule your furnace filter should be changed every 90 days. But if your furnace is leaking water, you should swap out the furnace filter after the repairs are made and before you turn your furnace back on.

A wet, dirty, or clogged filter will restrict airflow, and put extra strain on your furnace. It’s best to start fresh with a new/cleaned filter.

We’ll Find the Source of the Leak and Get Your Heat Back in No Time

No matter what make or model of furnace you have, we can make the necessary repairs.

Our team of technicians are highly-trained and professional, able to diagnose the problem and have you up and running again as quickly as possible

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