Hello again, if the high limit switch is starting to wear out, and trips prematurely, then replacing it will solve the problem for a while but it will not solve the cause.... the cause is established conclusively by lower water flow in the long run of tube to the hot tap.
If the over heat fuse blows, it will stay blown, and no allow the heater to resume heating at all until it is replaced...you had reported earlier that the heater would resume heating for a while after it tripped.
It is possible that fuse has since blown, however, if it has nothing would work at all.
Regarding data on the internet, it can be very good and accurate at times, and entirely or partially bogus at other times, or just not fully accurate to your situation as is most likely this time.
very few of those posting on the web are with verified credentials (as with us on Just answer we are all very thoughly vetted, and most of us with 98% or better accuracy scores... my accuracy rate is 98.8)
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