Aquahot changing sound

[Ck2hans]

Aquahot was completely rebuilt 2 years ago (new tank too). It has always had a low level high pitch whine, but has worked fine for two years now.
We have been living out of the coach for business for the last 3 months. All of a sudden the Aquahot is running quite a bit quieter, but still working great. Is this noise change to quieter something I should be concerned about?
Chuck

[Loc]

Chuck,

Maybe the bus gods are smiling on you. My Aquahot in my Millennium would make a whine sound when I had the pump turned on to heat the engine. Without the engine heat pump on, it was relatively quiet except when it fired up the boiler and cycled.

[freds]

Aquahot was completely rebuilt 2 years ago (new tank too). It has always had a low level high pitch whine, but has worked fine for two years now.
We have been living out of the coach for business for the last 3 months. All of a sudden the Aquahot is running quite a bit quieter, but still working great. Is this noise change to quieter something I should be concerned about?
Chuck

My Espar heater was whining. To make it go away I changed the bend in the exhaust hose.