Furnace Leaking Water

Furnace-Leaking-Water-Impressive-Climate-Control-Ottawa-400x500

You just realised your furnace leaking water in your newly finished basement, and not sure why. Under no circumstance should you ever see water around your furnace. There is a sign that something is leaking and not draining properly. It could be a simple fix and to begin troubleshooting, you don’t have to go in a panic mode. Depending on the season, a furnace leaking water should have you inspect different places to find the trigger of the leak. Mainly, overflowing evaporator drain pans used with furnace coils, air handler coils, mini splits, and even dehumidifiers create lots of insurance claims. More often than not, the mini-flood results from a lack of annual preventive maintenance: dirty coils, plugged drain lines, and loss of charge mean lots of water with nowhere beneficial to go.

– Improper Insulation 

During the cooling season, the indoor evaporator coil and the suction line sweat. The refrigerant lines should have black insulation (armaflex), to keep the condensation from dripping. Sometimes if the insulation is missing or if it has open seems, it can cause dripping and obviously, this is an easy fix. All arm flex joints should be butted up tight and well-taped.

Dirty Evaporator Coil

Your air conditioner evaporator coil produces a lot of condensation (water) during the summer. Eventually, this water runs down the coil into a drain pan, and then out to the drain. Once drained water goes either into the ground, outside the house, or into a condensate pump. Then, in turn, the pump takes the water either outside the house or into a plumbing drain. If the coil is dirty, then the water, instead of running down the coil, will hit the dirt, and then drip onto the floor. This is one reason why the coil should be cleaned annually, not to mention for efficiency reasons. Sometimes the indoor coil can ice up. And when the ice eventually melts, it drips onto the floor. Like water, you should never see ice anywhere on your system during the cooling season.

Clogged Evaporator Drain

Now if you have a dirty coil, the water will mix with the dirt and the dirt will end up in the pan. A dirty drain pan will get clogged and water leaks will appear in the basement. The bottom of the trap is the most common source of a clog and it can be cleaned out with a long flexible cleaning brush. Keep in mind, that it doesn’t take much dirt to clog a drain.

And if your unit is in an attic (Such as High Velocity) or a finished basement, this can cause terrible damage. This is another reason why it is important to always have a good, clean, properly sized air filter, along with annual inspections.

While many high-efficiency units have condensate directed to a nearby floor drain, some condensing furnaces or boilers must utilize a condensate pump sending the liquid to a remote drain elsewhere in the building.

Sometimes the condensate is pumped to a sink, laundry tub, or even outside. Pumping condensate to a receptacle that can be stopped-up is inviting a flood creating property damage. Ask your installer to ensure a secondary float switch is available. In the event of a condensate pump failure, the float switch will signal the control circuit to power down.

1. Proper Installation

Furnaces, water heaters, boilers, and air handlers should be installed on a solid concrete base raising the appliance about two inches above the floor, providing some protection from minor flooding.

2. Install Float Switch

Install a float switch in the evaporator coil secondary drain outlet.

3. Annual Maintenance

It is better to have a licensed gas technician inspect your drain pan, evaporator coil, and vents. Plus blow out the drain lines and clean traps on every maintenance call.

I have no answers for Mother Nature’s wrath; destructive overland flooding is a fact of life. However, on the HVAC side, we must do all we can to prevent as much water damage as possible. Our Licensed gas fitters use standard industry techniques and materials when on maintenance calls. They educate homeowners to better maintain their HVAC systems and offer protective devices where possible.

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