Daddyo
Guru
Sorry for the provocative title butI didn't know how else to word the question. A little background first. Our prior boat had a single Lehman 120 that ran at 180 degrees, checked with my inferred at cruise. Water heater water and bus heater were scalding hot. Exact same 120 on this boat with WH and bus heater on the loop and only moderately hot. Replaced thermostat and added circulating pump. Bleed system many times. I've checked the manifold and expansion tanks temps and all seem fine yet I can not get the hot water loop scalding as in the past. Why!!!!