Water Poured into Furnace Exhaust Pipe

Hi - a neighborhood child placed my sump pump hose into the furnace exhaust pipe (white PVC pipe sticking up) on the outside of my house. I believe it pumped through one cycle before I found it.

I discovered a large puddle of water below the furnace and water was in collection pans inside the furnace compartment. I turned off the furnace/AC, soaked up as much water as I could and pointed a fan at the unit to dry everything off.

I figure that it’s ok if some water gets in since the exhaust pipe is open with no cover - rain could easily blow in at anytime.

What can I do to make sure everything is ok? Could there be a big risk?

Thanks!