Get Help from Bob Vila
- Give-Aways & Offers
- Monthly Must Do's
- DIY Project Ideas
- Step-by-Step Guides
- Inspirational Photo Galleries
[This message has been edited by LDoyle (edited May 07, 2003).]
40 gallon 40,000 btu heater runs about 4 hours a day to keep the water hot, about 160,000 BTU's a day.
Tankless 100,000 BTU heater runs about 20 minutes a day, 33,000 BTU's used.
Thats around 127,000 BTU's a day not being used.
I have a propane powervent heater that I metered the vent motor to get the amount of time the heater runs per day.
I base the other one on taking 2 10 minute showers a day. There is a little more for when washing hands, but can't amount to more than a few minutes of use. The trick is to have the heater as close as possible to the faucets with these units. For my kitchen I am going with a small electric tankless unit since it is in the middle of the house and at least 30 feet or more from each heater. WE will be replacing the tank heater soon with another tankless unit for that section of the house.
If we were using natural gas, it wouldnt matter what we used, but since we are using propane, and its a limited supply, we want to conserve as much as possible, over $1000 to fill is pretty damn expensive.