Check the hose connects under the cushion. The hot side needs to be replace every couple of years. Also, check the anti-freese line under the sink if you see pink water. They may need to be tightened. You'll have to take the entire draw assembly out to get to them.

Jim

Richard,
I would also advise looking for the simple solution first. There are about 100 hose clamps in that area, all it takes is one loose one to cause a leak. Also, It is hard to tell exactly where the leak is coming from in that area.

A few thoughts:
Does the water pump cycle occasionally (usually in the middle of the night) when all faucets are off? If it does, the leak is on the high pressure side of the pump. If it does not, it is on the low pressure side.

The heater drain valve often leaks.

For what it is worth.
Dave

I have had to replace the fittings that go into the tank. While awkward to reach, they are threaded and are available as standard plumbing parts. Two of them developed leaks over time. You can easily see whether water is dripping from them. Another source for leaks for me was at a one-way valve that connects two pieces of tubing together. It keeps water from the heater from flowing back into the water pressure system. The original one on my boat was made of plastic and I replaced it with one made of brass. I have also had to tighten hose clamps. It has always been a relief to discover these inexpensive fixes rather than having to replace the heater itself.