Cold water sandwich effect

[tetstream]

We were out for a three night dry camp in our newish bambi. I took several "spit" showers, all the same. The water runs hot, then cool, then hot at the shower head. SPit shower means I just turn the head on enough to get parts to wash wet, soap up and then spit rinse.

Water heater heats for about 15 minutes, then shuts off. Then I shower. I run the shower on full hot until I get hot at the head, to run the cold water out of the lines. Then I take my shower, bascially on full hot to offset the cold water sandwich. I definately don't use the 6 gal capacity of the WH.

Acts like the hot water in the line between the WH and the shower cools down between the times I turn the shower head on. But that's hardly any time at all.

Ideas??

[richinny]

can you insulate any of the heated water line?

[tetstream]

Certainly I could insulate any of the hot water line that I could access. However, I'm not convinced that would solve the problem and may create more trouble.

In my experience with plumbiing houses, pipe wrap is good and bad. The bad is that once the pipe is filled with hot water, it takes a long time for the water to heat the cold mass of the pipe wrap around alll the line. Consequently, you run more water at the tap to get hot water, because the cooler mass of the pipe wrap takes the heat away from the initial hot water passing thru the pipe. Running extra hot water out of my limited fresh water supply and 6 gal HW tank is not what I want to be doing.

Besides, the temps around the trailer were in the 80's and 90's this weekend, so I would think that the lines would not loose much heat once raised to equilibrium with the passing water.

[boatdoc]

Originally Posted by tetstream

We were out for a three night dry camp in our newish bambi. I took several "spit" showers, all the same. The water runs hot, then cool, then hot at the shower head. SPit shower means I just turn the head on enough to get parts to wash wet, soap up and then spit rinse.

Water heater heats for about 15 minutes, then shuts off. Then I shower. I run the shower on full hot until I get hot at the head, to run the cold water out of the lines. Then I take my shower, bascially on full hot to offset the cold water sandwich. I definately don't use the 6 gal capacity of the WH.

Acts like the hot water in the line between the WH and the shower cools down between the times I turn the shower head on. But that's hardly any time at all.

Ideas??

Hi tetstream; You may have to install a back flow preventer check valve. There are some threads on this issue. Thanks "Boatdoc"