Water leaking around the base of the furnace or inside the blower compartment.

Safety first: Turn off power before working around water and electrical components.

Steps to check:

• Inspect condensate trap: On condensing Coleman furnaces, locate the plastic trap assembly near the inducer. Remove and flush with warm water to clear debris. Reassemble per the furnace manual.
• Check drain tubing: Ensure all hoses are firmly attached and not cracked. Replace brittle or leaking tubing.
• Verify slope: The drain line should slope continuously downward to the floor drain or pump. Adjust supports to eliminate sags where water can collect.
• Inspect secondary heat exchanger pan: If accessible, check for cracks or corrosion. A damaged pan may require replacement of the collector box assembly.

Persistent leaks can damage the furnace and surrounding structure; if you cannot locate the source, contact an HVAC technician.