On Wed, 29 Aug 2007 09:27:19 -0700, sonofabitchsky wrote:

Got a shower upstairs that works fine for about 5 minutes, then the
water gets really hot, then colder and so on. This is happening
without anyone in the house using anything. House was built in the
late 70's early 80's I guess with a newer water heater and copper
piping. Any ideas?


I would first look at pipe to see if it is plumbed correctly with proper
size. Quite likely someone may have cut corners when house was built.
This would not be the first time.