First thing to know is whether you have a standard gas (non-condensing) or high efficient gas condensing furnace.
- A Standard or mid efficient gas furnace is not designed to produce any kind of water. The vent piping or chimney pipes will be made of metal and likely connect to a masonry or double walled chimney pipe. A poorly designed or blocked exhaust pipe may allow the vent gasses to cool down prematurely and compromise the safety and operation of the unit. Water could also be coming from a humidifier or central a/c unit and appear to be coming from the furnace itself. Annual maintenance is of upmost importance to minimize the dangers of this situation.
- A High Efficient Condensing gas furnace has a secondary heat exchanger that will extract additional heat from the vent gases. The vent piping will be made of ABS or PVC plastic and most often pass through a wall to the outdoors. This absorbing of more heat also takes more time. Enough time in fact for the gases to cool down and condense into water before it leaves the furnace. Normally, high-efficiency furnaces drain away condensation via a draining system. But instead, if that water ends up on your floor, that’s a sign that there may be a problem with your furnace.
Problems with a Condensate Pump
Some high-efficiency furnaces in Winnipeg may use a condensate pump to push the condensate water towards a suitable drainage location.
A condensate pump is a small plastic box (size of a shoe box) connected to the furnace PVC drain pipe and pumps water toward the drain. It basically acts like a small sump pump.
If the condensate pump malfunctions or stops working altogether, you’ll see water dripping or overflowing from the device. Check the following before calling for service:
- Make sure the pump is plugged is if it is not hard-wired
- Check to see that both hoses are inserted into the pump case
- Make sure there are no kinks or obstructions in the drain hoses.
A Bad Heat Exchanger
Most discussions on heat exchangers involve the fact that they may be cracked or leaking. High efficient heat exchangers however run the risk of getting plugged up and restricting the required pathways for condensate droplets to gather and make their way out of the furnace. We can almost always contribute this type of failure to a poor installation or commissioning during the initial start-up. Unfortunately a bad heat exchanger can be a very expensive repair. You should have a professional Heating Contractor inspect the heat exchanger and give you proper advice on whether you should replace the part or replace the entire furnace. Most manufacturers offer lengthy warranties on heat exchangers but the labor component can be as much as $500 to $800. This together with the realization of the remaining expected safe and functional use of the other components can make it a challenging decision especially once a high efficient furnace is more than 10 or 12 years old.