attic solar water heater idea

jimphilly · 02-20-13, 03:14 PM

Hello everyone,
This is my first post.
I have a row home in Philadelphia with a black asphalt roof. It has an almost flat roof--just a slight slope for water drainage. I pulled down the second floor ceilings and am installing R38 batts of insulation.
Before I do that however, I want to install PEX tubing, (or should I use CPVC piping?) secured to the horizontal roof joists. The crawl space is about 11' by 30' by about 3' high. It gets quite hot in the summer. I want to use it to preheat the water going into my natural gas water heater. It would have a way of removing the water in the winter, when the area would be quite cold, by taking this "loop" out of the hot water system using manually operated shutoff valves.
The crawl space area "produces" useable heat between April and mid-October.
Comments please on the idea.

02-20-13, 03:14 PM	#1
jimphilly Lurking Renovator Join Date: Jan 2013 Location: Philadelphia Posts: 1 Thanks: 0 Thanked 0 Times in 0 Posts	attic solar water heater idea Hello everyone, This is my first post. I have a row home in Philadelphia with a black asphalt roof. It has an almost flat roof--just a slight slope for water drainage. I pulled down the second floor ceilings and am installing R38 batts of insulation. Before I do that however, I want to install PEX tubing, (or should I use CPVC piping?) secured to the horizontal roof joists. The crawl space is about 11' by 30' by about 3' high. It gets quite hot in the summer. I want to use it to preheat the water going into my natural gas water heater. It would have a way of removing the water in the winter, when the area would be quite cold, by taking this "loop" out of the hot water system using manually operated shutoff valves. The crawl space area "produces" useable heat between April and mid-October. Comments please on the idea.