Over the last few years tankless hot water heaters have become very popular. They come with a number of efficiency advantages when compared to their conventional tank type counterparts. But, things like the higher initial cost of tankless water heaters, and more complex installation can be viewed as negatives. So, are tankless water heaters all they’re cracked up to be, or do they come with drawbacks?
The most obvious benefit associated with tankless water heaters is their superior energy efficiency when compared to traditional tank type water heaters. These traditional tank type water heaters heat, reheat, and store hot water 24 hours a day, 7 days a week. Heating water when you’re not using it or not even home, results in substantial energy, or standby losses. Tankless hot water heaters, on the other hand, only heat water when it’s needed. These savings can be dramatic, as tankless water heaters use 30 to 50 percent less energy than units with tanks.
Endless Hot Water
One of the major flaws inherit with tank type water heaters is that they can only hold a certain amount of hot water. If this hot water runs out, so does your luck, as cold showers are less than desirable. Tankless (on demand or instantaneous) water heaters heat water instantly, with no reliance on storage. Tankless hot water heaters can insure that there is never a shortage of hot water, as long as it’s operating within its capacity.
Traditional tank water heaters store water in their tanks. Depending on the tanks age, they can have considerable scale and rust buildup. Using hot water from an old rusty tank is something many people do daily, without even thinking about it. Tankless water heaters, as the name implies, has no tank to collect buildup, water is simply heated as it’s passed through the unit. Also, the benefits of avoiding corrosion mean that tankless units will last much longer than tank types.
Due to the rather compact size of tankless hot water heaters, they can provide considerable space savings. Tankless water heater units can be utilized just about anywhere. Installation on walls, inside or outside, in attics or closets, are common. Small tankless electric water heaters can be stored under sinks. Gas tankless water heaters should be installed centrally, and proper precautions should be followed.
Current costs to purchase a tankless water heater are higher than that of traditional tank water heaters. They range in price from $150 for small point-of-use unit, to upwards of $1,200 for higher end gas-fired tankless water heaters. As a general rule, the more hot water a tankless unit can produce, the higher the cost. It’s important to weigh the higher initial cost of a tankless unit with the future operational cost savings, resulting in improved energy savings and longer life expectancy. Looking at the overall picture, initial cost may not be such a con, after all.
The installation costs associated with installing a tankless water heater unit are substantially higher than that of traditional tank units. These install costs are often predicated on the fuel type of your chosen tankless unit. Gas tankless water heaters are the most complicated installs. They require certain vent, combustion, and gas line requirements, this complicates the installation, which adds to the costs. Electrical tankless gas heaters are cheaper to install, but may require multiple circuits. New construction is the ideal time to install a tankless unit, as the costs are minimized. This would not be a do-it-yourself project unless you’re a contractor or have comparable skills.
Limited Flow Rate
All tankless water heaters are limited by flow rate. Many of the higher end units have a maximum flow rate of about 6 gallons per minute (GPM). So, even if you’ve got a tankless unit with suffucient BTU output, you’ll still be limited by flow rate. This could present problems for homes where multiple hot water taps are running simultaneously. If you’re running a bath, washing your clothes, and running the dishwasher, this could present some hot water shortages. A solution to flow rate issues might be to supplement with point-of-use units at heavy use locations, or even run gas units in parallel. Analyzing your simultaneous needs to determine your peak hot water flow demands is always recommended before selecting a tankless water heater.