Diavolicchio
Contemplation Leave
I'm building a new home this coming year that will be a well-insulated, air-tight, 1,380 sq ft cottage here on the Coast of Maine. One of the indulgences I'm allowing myself will be an shower in the main bathroom which will have six hydro-massage shower heads and the capacity at full bore to be using 15 gpm of water. Yes, at first glance, this probably sounds horribly wasteful and totally unnecessary, but I absolutely love a good, powerful shower massage and decided that I would allow myself this system if I could design it in such a way to keep the propane necessary to heat the water to a minimum.
I discovered some technology a few months back that I believe will help me accomplish this. Specifically, it's a GFX or Drain Heat Recovery System. In essence, it's a copper coil that wraps around the shower drain. As you take a shower and are flushing all of the energy in the hot water down the drain, the cold water that is about to be fed into your tankless water heater flows UP a copper coil wrapped around the drain, pre-heating the cold water significantly and at no cost (beyond that of the GFX itself.) Here's a photo of a commercial version of a GFX that is recovering over 60% of the energy that would otherwise simply be flushed down the drain:
The well water where I live in Maine is estimated to be around 46F in the winter and 56F in the summer. Taking this as a yearly average of 51F, this water gets preheated by the GFX by a rise of 24 degrees, bringing it up to 75F before it hits the water heater. The water heater therefore only has to burn enough propane to bring the water from 75F to 110F, the temperature at which it exists the shower heads.
I've done the math on this and it turns out that if I take two 20 minute showers a day running all six shower heads at capacity (or two 30 minutes showers running 4 out of 6 heads) each shower will require around $2.40 in propane. Yes, that's a ton of water, but it would feel like heaven after a long hard day working outdoors.
For the record, I'll be using my own well water and recycling it right back into my own land. I also work from a home office, drive relatively little, and would be using the propane equivalent of 1-1/3 gallons of gasoline each day for showers, just to put things in perspective.
I'm curious to hear if anyone else on here is using a Drain Heat Recovery System and if so what your experiences have been. Have you been able to get the rise in water temperature that the system promised? I'd love to hear more about it. I'm also very much open to suggestions for other cost-effective system for preheating and storing water. The Apricus evacuated solar tubes may be a possibility as well.
I discovered some technology a few months back that I believe will help me accomplish this. Specifically, it's a GFX or Drain Heat Recovery System. In essence, it's a copper coil that wraps around the shower drain. As you take a shower and are flushing all of the energy in the hot water down the drain, the cold water that is about to be fed into your tankless water heater flows UP a copper coil wrapped around the drain, pre-heating the cold water significantly and at no cost (beyond that of the GFX itself.) Here's a photo of a commercial version of a GFX that is recovering over 60% of the energy that would otherwise simply be flushed down the drain:
The well water where I live in Maine is estimated to be around 46F in the winter and 56F in the summer. Taking this as a yearly average of 51F, this water gets preheated by the GFX by a rise of 24 degrees, bringing it up to 75F before it hits the water heater. The water heater therefore only has to burn enough propane to bring the water from 75F to 110F, the temperature at which it exists the shower heads.
I've done the math on this and it turns out that if I take two 20 minute showers a day running all six shower heads at capacity (or two 30 minutes showers running 4 out of 6 heads) each shower will require around $2.40 in propane. Yes, that's a ton of water, but it would feel like heaven after a long hard day working outdoors.
For the record, I'll be using my own well water and recycling it right back into my own land. I also work from a home office, drive relatively little, and would be using the propane equivalent of 1-1/3 gallons of gasoline each day for showers, just to put things in perspective.
I'm curious to hear if anyone else on here is using a Drain Heat Recovery System and if so what your experiences have been. Have you been able to get the rise in water temperature that the system promised? I'd love to hear more about it. I'm also very much open to suggestions for other cost-effective system for preheating and storing water. The Apricus evacuated solar tubes may be a possibility as well.
