"Ashton Crusher" wrote in message
news
On Sat, 8 Aug 2015 10:28:16 -0400, "Robert Green"
wrote:

stuff snipped

You would also think that heating the water causes more sediment to
dissolve
so I am not sure exactly what most causes gunk buildup. I suspect it's
the
quality of the water, but I haven't seen any study that apportions the
causes of sedimentation.

Yes, you would think heating it would make it dissolve stuff, not
precipitate it but perhaps the fact that it just sits there perking
away (figuratively) much of the day with no water movement somehow
results in precipitates dropping out. Or perhaps the mixing of cold
and hot water causes precipitation regardless of it being on average
quite hot and lessening the high temp results in less of that presumed
effect.

Well, I'll keep looking. What's clear is that gunk DOES build up and with
some heaters/areas it builds up pretty quickly. It would be nice if
lowering the temperature not only saved money, but lengthened the service
life of the heater. We'll get at least one more data point when mine
finally goes. I started seeing some water dripping lately. Maybe I'll find
out soon. )-:

--
Bobby G.