Replies

1. GBA Editor
   Martin Holladay|Apr 14, 2011 04:12am|#1

   Jack,
   1. Check your local environmental regulations; there may be a law against pumping stream water to your house and returning the water to the stream at a different temperature. Heat pumps lower the water temperature in winter and raise it in the summer.

   2. Considering the cost of the equipment and the excavation required to dig a trench that is 500 feet long, as well as the pumping energy required to move the water, my guess is that your proposal will cost much more than a ductless minisplit air-source heat pump. The Mitsubishi HyperHeat works down to about -17 degrees F; if it is much colder than that for long periods of time where you live, you might need electric-resistance backup.

2. 
   Jack Woolfe|Apr 14, 2011 07:16am|#2

   Martin,
   I thought of digging a shallow well near the stream for the water source, rather than pumping directly from the stream. The well would both filter the water of debris as well as protecting the pipe from damage by floating ice, etc. Hopefully, using a well would not trigger environmental regulations.

   可以从接近32度水中提取多少热量的任何想法？空气热泵正在从低于冻结的空气中提取热量，因为空气不会冻结（虽然空气中的水分可以冻结），但如果你从水中提取足够的热量以使你陷入困境的温度下降。

   I wondered about the energy costs of pumping the water such a distance. Your comments heightens my concern. I wonder if there is a rough, back of the envelope, way to calculate energy losses from pumping? Would it be more energy cost effective to pipe the waste water back to near its source, and thus use the weight of the waste water to help pull up the fresh water (at the cost of greater intra-pipe resistance and material cost), or would it be better to just dump the waste water out on the ground?

3. 
   James Morgan|Apr 14, 2011 06:35pm|#3

   我的信封猜测是，当天气开始变冷时，你在没有时间平整的时间冻结浅井固体，在大部分冬天，你都会在抵抗力上奔跑。但请咨询一个声誉良好的GSHP安装人员，以获得对您局势的知情评估。除非你能负担得起一些严重的昂贵的错误，否则这不是一个弥补的项目。

4. 
   Zac McCormick|Apr 14, 2011 10:31pm|#4

   我不会试图通过热泵直接运行任何种类的地表水，特别是接近冻结。您可以考虑利用水流中的闭环防冻电路。例如，我已经看到有铜线线圈的系统，其中悬挂在蓄电池中的防冻电路，其中河流水贯穿。可以获得像经过专业设计的东西。

5. 
   Jack Woolfe|Apr 15, 2011 09:18am|#5

   Martin, James and Zac,
   Thanks for your good thoughts. It does look like I should get expert advise. I wouldn't have thought a shallow well, essentially at river level, would freeze up in the winter -- at least as long as I didn't dump the chilled water back into the well. I get my potable water from a spring, which doesn't freeze up in the winter. The antifreeze circuit should like a good idea, to keep the heat pump clean.