Again, the most common reason for a leaking furnace is a condensation leak. High-efficiency furnaces extract heat from the combustion gases for a longer period of time than a standard-efficiency furnace does, causing the gases to cool, then condense. The condensation is routed to a floor drain.

Why is there water dripping from my furnace vent?

When a high efficiency furnace releases the exhaust gases, condensation is created. This condensation is a significant amount of moisture on the PVC pipe, and it needs to be drained either into a floor drain or a condensation pump. A water leakage occurs when the condensation is unable to drain properly.

Why is there condensation in my furnace exhaust pipe?





So why is your furnace exhaust pipe leaking water? It could be that the exhaust pipe is the incorrect size. This could lead to the furnace exhaust cooling down within the pipe, condensing and becoming water vapor, causing a condensation leak.

Why is my flue pipe leaking water?

So why is the furnace exhaust pipe leaking water? The incorrect size of the exhaust pipe is often responsible for the condensation leak. As the furnace exhaust cools down within the pipe, condenses, and becomes water vapor, it leads to condensation leak.

What is the pipe coming out of the furnace?

If your furnace is 90% efficient or greater, you probably have PVC pipes coming out of the wall of your home that look something like those pictured here. These pipes allow the furnace to intake fresh air and to safely vent flue gasses out of the home.

How do you unclog a furnace vent pipe?

Scrub the inside free of any dust and debris; then use the handheld vacuum to get out as much as you can. Wipe it clear with a rag or soft cloth and then replace the cap. Cut away any branches or remove any object that might be obstructing the pipe and creating debris. The vent should always be clear.

What is the small pipe on the side of house dripping water?





What is an overflow pipe? An overflow pipe leads from a water storage tank or cistern inside your home to the outside. They’re a vital part of your home’s plumbing system.

How do I stop condensation in my furnace vent?

Adjust the furnace temperature: Make sure that the furnace temperature is hot enough for the gases to freely flow through the flue and out into the atmosphere. Improve the flue design: Have a professional HVAC tech look at your flue and recommend improvements to the flue’s design.

What causes flue gas condensation?

Flue gas will form and condense on a heat exchanger and in the boiler stack when it falls below its dew point, and this occurs when the return water temps of the system are around 135°F. The vapor of the flue gas undergoes a phase change into a liquid which is now acidic with a pH typically between 2–5.

How do you tell if your furnace vent is clogged?

How to tell if your exhaust vent is blocked

  1. Furnace doesn’t heat the air. By far, the most common symptom of a blocked exhaust vent is a furnace that doesn’t heat up. …
  2. Furnace heats up for a little while, then shuts off. …
  3. Furnace cover panel gets hot. …
  4. Bad smells when your furnace is heating.



How do you tell if your vents are clogged?

The biggest symptom of clogged air ducts in your home is a difference in temperatures. This is most likely to occur if you set your whole-home thermostat to the desired temperature and then notice that one room isn’t as warm or cool as the others.

Does a furnace vent need a cap?

The top of a chimney after installation does not always have a chimney cap. You will likely need to install a cap for your gas furnace chimney, but not for the reasons you might think.

What does a gas vent cap do?



Gas can vent caps, like a rain cap provide a means to dispense fuel, water, and other liquids quickly and smoothly.

How do you change a gas cap on a vent?

Quote from the video:
Quote from Youtube video: It's really simple just pop the old one off. And let the other one. Off. There you go thank you that's all the only final touches. Take some weather wood paint.