Is it Normal For Water to Pool in a Pan Under the Central Heating Unit?

Water under your heating system could indicate a problem.

Water pooling anywhere around your home can be alarming. When the water localizes in a specific place, you can pinpoint its origin. Water pooling under a central heating unit likely came from the appliance itself and not from another source. This will be helpful in diagnosing and solving the problem.

Types of Heating Units

The type of central heater you have will determine if the water dripping is normal or not. It will be acceptable in some types of heaters, but not in others. Look at your heater to determine if it is a hydronic or steam system that operates with a boiler, a furnace or a heat pump that is tied into your central air conditioning.

Heat Pump Leaking

Heat pumps are tied into air conditioning units and used in areas with milder climates. During the winter, the air conditioning mechanism uses the refrigerant to pull warmth out of the air outside and transfer it inside while pulling cold air out of your home. The refrigerant in these systems condenses and evaporates to achieve this. Through this process, water forms around the pipes of the evaporator coil. A drain pipe is placed under this to collect the condensation and prevent it from damaging your home. If your system's drain pipe gets blocked with algae or mold, condensation will back up into the pan. Clearing the drain line with bleach will help future condensation to flow through the pipe instead of spilling into the drip pan.

Boiler Leaking

Boilers are used to heat water to send through pipes in your home for radiators or baseboard heating systems. Since these appliances use water, standing water under the heating system a water leak from the system is possible, and it is more likely to indicate a problem. If you see water under a central heating system that uses a boiler, contact an HVAC heating technician immediately. He will check for and repair any leaks found in the boiler or pipework around it.

Furnace Leaking

Furnaces heat air and use a blower to circulate it through ducts in your home. Some high-efficiency furnaces produce condensation. This can pool under the furnace in the normal operation of the appliance. Other types of furnaces have humidifiers attached to them. The drain hose on these units can clog, leading to water standing on the floor under the furnace, where the humidifier is attached. Clear out the drain line and check for clogs. If water still pools, contact an HVAC technician for service.

References

• "Refrigeration and Air Conditioning Technology"; William C. Whitman, et al.
• "Black & Decker Complete Photo Guide to Home Repair"; Jennifer Gehlhar
• "Hot Water Boilers"; Carson Dunlop & Associates
• "Essentials of Home Inspection: Home Reference Book"; Carson Dunlop & Associates