Finding water leaking from your furnace can be a concerning situation, but understanding the potential causes and knowing the right steps to take can help you address the issue quickly and efficiently. Whether the leak is from a clogged condensate line, a malfunctioning pump, or an issue with the furnace’s heat exchanger, it's important to act fast to prevent water damage and further complications. In this article, we’ll walk you through the steps to take when you discover water pooling around your furnace, how to troubleshoot the problem, and when to call a professional for repairs.

If you're system is in heating mode, The good news is the water around your furnace is not the cause of a leaking water line. Its actually made by the furnace itself. See when your furnace runs it burns natural gas which is actually just Methane(CH4) and so the methane when it burns will split the hydrogen from the methane and bond with the oxygen to make water(H20) which is then condensed and removed from the furnace by the drain system. In this case the most likely cause for the leaking water is that the furnace drain is clogged or a drain tube has come loose or a gasket has failed. in this case there isn't much to do except visually inspect the external drain lines of the furnace and then call HVAC ASAP to check it out

Alternatively if there is a large amount of water around the furnace and you are using the A/C there are a few more possibilities. The first thing to check is the furnace filter. when the furnace filter is clogged up it slows down the air moving through the AC coil and so instead of cooling your house the ac cools itself which causes the moisture in the air to freeze onto the coil. this will cause lots of havoc to the system as there is a giant block of ice on top of the furnace where the air condition coil is. this is why its so important to change your filters regularly. once the system turns off the ice that is on the coil will start to melt and then overwhelm the water collection system in the ac coil causing it to overflow and leak water onto the furnace.

The water generated by the AC is actually completely different than the water that is generated by the furnace and has a completely different process of being removed from the equipment. The water that is created by the air conditioner is actually moisture that is being removed from the air via condensation. this is because when the air conditioning coil inside the furnace gets cold the water inside the air sticks to the coil. Just like a cold drink when it leaves the fridge. inside the coil there is a collection system for this water and it uses gravity to flow out of the AC and into the floor drain or condensate pump. Similarly to the Furnace sometimes if the drain becomes clogged this will cause the drain system to back up and overflow onto the furnace which is really damaging to the equipment. Bare metal and water are not a great combo at all.

If you've had duct cleaning recently this can also be the culprit. even when the duct is blocked off sometimes the debris and dust inside the ductwork ends up on top of the furnace and on the ac coil if it has enough momentum it can overshoot the vacuum that attaches to the ducts and often what happens is the coil and the collection system gets clogged up with dust and debris which will stop the water from flowing out of the coil. this will cause the water to overflow onto the furnace. a way you can see if this is the cause is by unplugging the ac drain tube(usually black tube) that comes out of your ductwork above the furnace which usually looks something like this

Once this little drain connection is removed sometimes it can be cleaned and cleared of debris to unblock the drain and sometimes the debris is inside the drain channel a little further and you might need to use a pipe cleaner or something small to dig out any debris. be careful though when this part is removed it might have 2-3 liters of water behind it that's been building up over the past few days of ac use so have something ready to catch the water underneath.

If you're still having trouble with your air conditioning leaking water and are running out of ideas give us a call at HVAC ASAP and well get your AC back up and running in no time at all