water leaking onto front floorboard, passenger side, plastic pipe break?

Thank you! That hose drains water freely to the outside. I unclogged it with air hose a few months ago. i keep carpet pulled back and i use towels on floor board every day to soak up the water draining from the passenger side firewall compartment. Could the heater housing possibly not be sealed? If so, can I just pull up the padding at bulkhead to get to it? Or do i have to take dashboard apart? What type if sealant can i use? Something gooey like 'dum-dum' or...?? THNK YOU for your time and assistance!