Help need

hi all was wondering if anyone could shed some light on my problem. I own a mk1 1.5 gx and for some reason I'm losing water. I've fitted a new water pump new rad and replaced all the hoses for new one plus new header tank. Ant help would be very greatful 

Are your carpets damp? Could be a heater matrix. Or…

I bought an aftermarket heater valve and it leaked. Changed it for a vw component. Problem fixed. Cheap no good. Good no cheap. 

Yeah carpet is damp on the drivers side. I think ill replace that an see how I get on. Thanks for the help