My sister's water heater just died on her this week, so she's been researching the advantages and costs of transitioning to a tankless water heater. If you've been thinking about switching to one when your water heater poops out, here's some basic info to think about.
1. Tankless water heaters only heat water as you need it, rather than storing it and waiting for it to be used. This form of heating water as needed usually saves 10-20% off your water heater portion of your bill. Since water heaters eat up approximately 14% of your bill, this can be a good amount of savings!
2. Besides energy savings, tankless heaters use less materials and require less energy consumption in regards to production and transportation to stores.
3. Life expectancy is longer - tankless heaters have a life expectancy of around 20 years, compared to conventional water heater's 10-15 years.
Costs and Disadvantages:
1. The cost of a gas tankless water heater will run you 2-4x the cost of installation as a regular water heater, due to needing to retro-fit existing houses with wider gas supply lines and heavier cable or multiple circuits to draw more power. New construction is the best time to install a tankless heater to save on retro-fit costs
2.Water usage can sometimes be limited if you're planning on running two showers at once, as well as laundry or the dishwasher. Large full-house tankless units can pump out over 5 gallons per minute for gas, and around 3 gallons per minute for electric. If you don't usually run more than 2 water-consuming devices at a time, you should be fine.
All in all, if you're needing to replace your hot water heater, a tankless unit might be the way to go. Even if you plan on moving from your home in the next few years, it's a great selling point to buyers to have a tankless water heater. "Green" is in!