I have a suburban hot water system inside the van and our last trip the unit is working fine but if i leave the pump on for water when running 12v the over flow of the hot water just keeps pumping out water. I have checked the relief valve released pressure and turned back on but same result. Pump just keeps running as if i have a tap on and when checking the overflow again water is coming out at a steady rate, no dripping. Anybody had a similar issue?