[Greenbuilding] [BULK] Hot Water Return Revisited WAS Windows

[Gennaro Brooks-Church]

Here is an example of a system I am installing right now. It has hot
water home run, hot water return and then hot/cold water mixing just
before returning to the boiler. The system is pump driven that has a
timer so it is only on during peap times. The pump is also variable
speed and connected to a temperature sensor so that it slows to a
trickle once a certain temperature is met.

http://ecobrooklyn.com/hot-water-home-run-return-mixing/

The only thing I don't get is the mixing of the hot water return with
incoming cold water from the mains. The reason I am told is that this
raises the temperature of the incoming water and makes the boiler work
less. But doesn't that defeat the purpose of a hot water return?

Can anyone give insight on this?

Gennaro Brooks-Church
Cell: 1 347 244 3016 USA
www.EcoBrooklyn.com




On Fri, Feb 20, 2009 at 5:36 PM, Corwyn <corwyn at midcoast.com> wrote:
>
>
> njh wrote:
>>
>> You don't need a pump, merely a pressure differential.  You could do this
>> using a thermostatic valve, a pressure reducing valve, two check valves and
>> a pressure vessel.  (A clever person could make all of these in a single
>> HDPE unit)
>>
>> Hot tap turns on, water flows from hot tank to cold pressure vessel, water
>> warms up, thermostatic valve opens and out comes water.
>>
>> Cold tap turns on, water flows out from pressure vessel until below
>> pressure reducing valve pressure, flows from mains.  The cold water could be
>> dumped into a non picky load such as toilet cistern.
>
> Could you draw a diagram, I don't think I am getting exactly how this
> would work.
>
> Thank You Kindly,
>
> Corwyn
>
> --
> Topher Belknap
> Green Fret Consulting
> Kermit didn't know the half of it...
> http://www.greenfret.com/
> topher at greenfret.com
> (207) 882-7652
>
>
>
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