You need to find out what the pipe is. It could be one of the following:
- AC condensate drain. It is supposed to drip, especially when the AC is running. But, check the condensate drain pan in the HVAC unit to see if it is full of water.
- Overflow drain line from the water heater drain pan. It will only drip when the water heater has a leak, or if the relief valve has tripped. Is there water in the drain pan under the water heater?
- If you have a water softener, it could be the backflush drain. This will spew out a lot of water during the backflush cycle.
|