Heater leaking any Ideas?

Yesterday while riding I found that my heater is leaking water in my boat. Today I checked the hoses to see if they might be the leaking point but I don't think they are. I don't know what the inards of the heater consist of, but I suspect that the leak is inside. Has anyone had a leaking heater? Any suggestions of things I can check without having to take it to the dealer? It's under warranty but I hate to wait 2 weeks to get my boat in for a heater leak. Can I just by-pass the heater by bridging the two hoses? Thanks.