[Pluto]

I just ordered some century heat transfer fluid to refill the overflow tank on the aquahot because the level has slowly been dropping. 

I thought it might have something to do with the heater running, but on closer inspection I noticed that there was a small puddle of fluid near the back of the unit.  Looking around some more i found that coolant had been running down the AH exhaust pipe and making a puddle on the ground.

I'm not seeing a leak around any of the external piping or pumps so I'm assuming that it's coming for inside of the unit itself. 

I haven't found much in the manual about a leak and or how to fix it.  I am assuming that it's going to be a major operation to fix the problem but I don't know.

Does anyone know or have an idea of what could be leaking on the inside of the aquahot? 

Thanks in advance,
Tyler