Why Is My Furnace Leaking Water?

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Why Is My Furnace Leaking Water?

Leaks are a fairly common issue for furnaces. 

There are several reasons they happen; some major, others minor.

If you come home to a furnace leaking water, you’ll most likely need a technician to come out, diagnose the problem, and repair your furnace.

Let’s go over the primary reasons for water leaks in a furnace.

Why Furnaces Leak Water

If you notice water around the base of your furnace, it needs to be remedied right away.

Leaks can cause huge issues, including damaging parts, flooring, and walls, leading to mold growth.

Let’s look at the most common reasons for a furnace leaking water.

Condensation Leak

Condensation leaks are one of the most common reasons for a furnace leaking water. 

Many furnaces run at high efficiency, which means an AFUE rating of either 90 or above. 

This type of furnace contains two heat exchangers that help it produce more heat.

Condensation caused by the production of heat must get carried out of your home via pipes. 

When these pipes either get clogged or break, you’ll get leaking condensation around the base of the furnace. 

Leaking Humidifier

A built-in humidifier can add comfort by keeping your home’s indoor humidity levels balanced, but it can also be an unexpected source of furnace leaks. 

Any HVAC system with a built-in humidifier will have a plumbing to supply that humidifier with water. 

These water lines can develop leaks throughout their lifespan, resulting in a furnace leak.

A Plumbing Leak

Finding your furnace leaking water may mean there’s an issue with the plumbing and not the furnace itself. 

There actually may not be an issue with the furnace’s components, which is a good thing. 

However, the leak still needs to be addressed.

When a clogged or broken plumbing pipe causes a backup in the drainage system, it seems as though the furnace is leaking. 

Damaged Heat Exchanger 

A problem with the heat exchanger in your furnace could cause a water leak and, unfortunately, is one of the most expensive repairs. 

If you’ve looked into the other possible causes of a leak and can’t find it, it may be the heat exchanger.

A new unit may need to be installed. A technician will be able to advise you on whether this needs to happen.

What to Do When You Notice a Leak

When you notice water dripping from your furnace or pooling up at the base, you need to act fast. 

Before a professional comes to your home to diagnose the issue, it’s essential to do a few things.

First, shut the entire system off. 

You should see a switch on or next to the furnace. If you can’t find this, turn the unit off at the breaker.

You’ll need to clean up all the water that has pooled up around the unit. 

It’s important to soak up all water thoroughly, as water damage happens quickly. 

If you can tell exactly where the leak is coming from, this will give you a good indication of what the problem is. 

However, you’re likely going to need professional furnace repair.

Denver Furnace Repair by First String Heating

If you notice your furnace leaking water or have another heating system problem to deal with, don’t hesitate to contact us at First String Heating.



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