Why would a furnace leak water at the base?
Usually the condensation from a high-efficiency gas furnace is channeled to a floor drain. Your leak could be a result of the condensation tubing becoming clogged or from breaks in the line. It could also be a result of the floor drain becoming clogged.
A standard-efficiency furnace, which has a metal exhaust pipe, should not have condensation. If it does, it could mean that the flue pipe was incorrectly sized. That could allow the hot exhaust to cool down and condense in the pipe, then drain back to the furnace and leak out.
Why a high-efficiency furnace creates condensation:
Why in the world would a high efficiency furnace create condensation?
It is about how the furnace extracts heat from combustion gases .
A lower-efficiency furnace extracts some heat from combustion gases and then quickly vents them out the flue pipe.
However a high-efficiency furnace, to extract more heat, has 2 heat exchangers. These allow the furnace to extract heat from the gases for a longer period of time. This causes the combustion gases to cool and then condense.
That condensation then exits out of your home through a drain. But if that water is pooling around the furnace, there’s a problem preventing it from draining properly.
The main causes of a condensation leak around a high-efficiency furnace:
- Clogged condensation tubing
- Clogged condensation drain
- Breaks in the condensation line
- Issues with the condensate pump (if you have one)
You’ll need a Heater Repair technician to diagnose which of these is the issue and then fix it.
Other causes of leaking water around a furnace…
Faulty furnace secondary heat exchanger
If you don’t have a furnace condensation issue, it’s possible that the secondary heat exchanger is the source of water around your furnace.
Hopefully not as that could be an expensive fix, and it might even require a complete furnace replacement.
Issue with furnace humidifier
You could also have an issue with your humidifier, which could be leaking inside your furnace.
If you’ve had an annual HVAC service check, as is suggested by HVAC Philly for all Bucks County, Montgomery County and greater Philadelphia area residents, this is an unlikely scenario because your service technician would have alerted you to the issue early.
If you have neglected that tune-up, you should call for it now because if this is your problem, the leak could do a lot of internal damage to your furnace.
Internal drain system clog
There is another possibility. If your air conditioning unit is still operating and it shares an internal drain with your furnace, you could have an internal drain system plug, which is sending water to the furnace.
While we can’t diagnose your issue precisely, don’t let this go too much longer. It’s a clear sign that you need to call in professional help. HVAC Philly is available to assist 24/7 for any emergency situation. Servicing the greater Philadelphia, Bucks County and Montgomery County area.
Leaks can cause huge issues, including damaging parts, flooring and walls, and lead to mold growth. A reputable heating and cooling specialist, like HVAC Philly, should be able to quickly diagnose the source of the leak and offer solutions to your water furnace problem.
Do your homework and get more than one estimate before you act, but get started now.