Intermittent hot cold water issue

[RDT]

Hi guys, I have an 02 43 open.  Having an issue with water temperature fluxuation on all of my fixtures.  Shower is particularly bad (and most important).  I tried changing the mixer valve in the shower-that didn’t work.  It seems that when the water pump cycles on and off correlates with the temperature changing.  I checked the inline filter at the pump it was clean.

Any thoughts on what I should be looking at?  Thanks!

[egstasea]

Check to if the hot water tank valves were left in bypass.

[RDT]

Thanks egstasea, first year dewinterizing this boat. Previous owner plumbed in a bypass system, I have both valves open (they are right on the tank). I believe that is correct-But I am not sure, does that sound right to you? Thanks again!

[egstasea]

My 40 Express has diverting valves (three ports) on both cold in and hot out.  The horizontal position allows the water to flow through the heater and the vertical position the water flows through the bypass.  It took some trial and error to figure mine out.