How to find which pipe leads where

[Brent1369]

We are going to install a rainwater pump but I have no idea which pipe leads to where ( like toilet washing machine) is there any way how I can find this out?

 

[Sylvan]

Dye test.

Place some dye inside one of the pipes and then look at the discharge by the house trap

 

[Sponsor]

 

[Fitter30]

Air compressor blow water backwards from the device just use 5-10 lbs

 

[DIYorBust]

Air compressor blow water backwards from the device just use 5-10 lbs

I once saw a plumber blow into a pipe for this purpose. It didn't look like the best way.