Re: [GBlist] recirculators

[Speireag Alden <Joshua.M.Alden.91@alum.dartmouth.org>]

Sgrìobh David Porter:

>I had a recirculator pump installed and an insulated copper pipe run through
>the attic from the tank to the master bath lav.  That created a loop for the
>house.  For the first couple of months, the recirculator ran 24 hours per
>day; until I got the electric bill.  I was paying $40 per month extra, it
>seemed, for the cost of the recirculator pump and the constant reheating of
>the water coming back into the tank.  Knowing that the recirculator pump
>used about as much as a 60W light bulb, I then attributed most of the extra
>electrical cost to the fact that the water tank was constantly receiving
>back into it, 90 degree water.  In order for the tank to raise the
>temperature back up to the thermostat setting of 120 degrees, the tank was
>always in the heating mode, at least with one of the two elements inside the
>tank.

     David gives us some useful figures.  If your situation is roughly 
parallel, and your layout permits it, an additional tankless heater 
at $600 will pay for itself in just a little over a year.  If your 
situation is twice as good as David's (through pipe insulation, 
shorter runs, etc.) then you still have a payback in around three 
years.  Pretty good investment.

     So, if you have a remote location which needs hot water, but you 
can live with just one tap's worth at a time, run cold water to that 
location and put it through the heater.  Or run the hot water line to 
the heater, and let the tankless heater modulate when it gets hot 
water from the line.

-Speireag.
-- 
Speireag Alden, aka Joshua Macdonald Alden

If the biota, in the course of aeons, has built something we like but 
do not understand, then who but a fool would discard seemingly 
useless parts?  To keep every cog and wheel is the first precaution 
of intelligent tinkering.   -- Aldo Leopold, _A Sand County Almanac_ 

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