Water Heater … Boring! Right? Well, not so fast! … especially if you are considering the purchase of a new to-be-built home, but also if you are considering some significant remodeling.
Long pipe-runs from the water heater to the kitchen and/or bath rooms will add significantly to energy costs unless the system is designed to minimize, or eliminate, the heat loss. Plus, letting the water run for a shower until the hot water arrives can waste a lot of water over time. And a tank too small for the size of the family/group simultaneously needing to use hot water for showers, baths, laundry and/or dish washing can cause great irritation when some of those showers must be delayed while the water heater is refilled and reheated.
So what are the design issues?
- Family/group size and size of bath tubs – what is the likely hot water demand to be?
- Gas or electric? Gas is more energy efficient for heating water, but some homes are all-electric. Most varieties of water heater can be either electric or gas fueled.
- Tank size – 50 gallon is most typical and sufficient in most cases, but are available in various sizes up to 98 gallons at retailers.
- Tankless – installed at the point-of-use. Most energy efficient and water efficient, but costly to install to the point of being not feasible for a retro-fit.
- Recirculating – for instant hot water from a central source. To minimize energy loss, the pipes must be very well insulated. Deserves serious consideration for a new home.
- Multiple Tanks – nearly mandatory for very large homes, while not feasible for small homes.
- Heat-pump – same technology as use for AC units. A small heat-pump sits right on top of the electric water heater pulling heat out of the surrounding air … VERY efficient during the summer when the water heater is located in the garage, especially in southern Arizona.
- Solar panel electric energy source – work great, but rebates and incentives have diminished.
What about maintenance? With the rather “hard” water in the metro-Phoenix area, the typical life span for a water heater is about six years for electric and ten for gas. The scale buildup on the heating element is commonly the reason for failure. Two maintenance procedures can significantly extend the life of a water heater:
- Semi-annual partial draining of the tank – just hook up a water hose to the water tank drain faucet and drain out three-to-five gallons. With that water will go the sediment that’s collected in the bottom of the tank.
- For an electric water heater, on four-year intervals, replace the anode rod, the heating element. These get heavily corroded by the minerals in the hard water. The parts are available at Home Depot and elsewhere.