waterheatertimer.org
Do-it-yourself
Average
temperature of
shallow ground water
 |
| Visit forum on fireplaces, stoves & chimneys |
 | Indirect heater stores geothermal heat |
| See new water heater ideas | |
| 54° | Approx annual average outdoor temperature for northern US states |
| 65° | Approx annual average outdoor temperature for southern US states |
 |
| Passively pre-heat cold water using staging tank or tempering tank located in naturally warm area See illustrations |
Is
shallow water temp same as shallow ground temp?
Casual proof: As former caver or spelunker, I observed year-round underground temps.
Once past the entrance, caves remain same temp year-round. Caves get temperature from average underground temperature in region. For example, limestone caves in Indiana are 54°F year-round, summer or winter. Southern caves are warmer. The map shows same temps I saw inside caves.
Note: There are three ways of talking about underground temperature.
1. Shallow temps might start at 8-12 feet deep.
2. Deep underground, up to 5 miles in some diamond mines. Deep diamond mines reach very high temps read1 read2
3. Geothermal hot spots from volcanic activity. Cause extremely high temps near surface.
For data, search US Geological Survey: http://www.usgs.gov/
For cave info: http://en.wikipedia.org/wiki/Caving see links at bottom
For geothermal: See #27 on my page: 9 ways to save with a water heater
For research: Use 'google alert' in e-mail, shows all relevant posts that day : http://www.google.com/alerts
See charts showing formula & cost of heating water: Family chart for setting water heater timer
 | Do-it-yourself
water heater timer & how-to |