Replacing a water heater is not something which every homeowner thinks to do of their own accord. Since after installation a good water heating system is mostly “out-of-sight out-of-mind”, it can be hard to know when yours needs replacing unless it starts to break down. But you should absolutely be looking to replace any hot water system which is approaching or past the end of its warranty, and sometimes even sooner. For instance, houses with hard water will need to replace their water heaters more regularly, as this water wears the heaters down quickly.
When trying to source your new water heater, look carefully: they typically last 10-15 years, so the efficiency and reliability of the device will potentially have a significant effect on your finances over time. Here are some of the most important criteria to consider for each heater:
Fuel type
The energy source of a heater can determine many of its other characteristics, such as energy efficiency, availability and price. The most complicated aspect of your heating system, it’s important to consider the options.
The most common type of heaters use some combination of electrical and natural gas, but geothermal and solar-powered models offer enticing benefits in energy efficiency and environmental footprint.
Size of Tank
The size of the tank in a system determines how much hot water it can deliver, and how often. While larger tanks take more energy to heat, they may be necessary for busy households who consistently use multiple streams of hot water over a peak period (such as morning showers/breakfast/laundry). Look into the FHR (First Hour Rating), which measures the amount of hot water the system can deliver over an hour.
If your hot water needs are particularly low – such as a 1- or 2-person household which rarely uses more than one source of hot water at a time – then you may benefit from a “demand” heater, which has no tank at all and heats water on an as-needed basis.
Energy efficiency
Since it can have a huge impact on long-term costs, you should have a good idea how energy efficient your potential heater is before making the decision to buy. Consumer ratings such as ENERGY STAR can help you gauge the efficiency of individual models, but much of their performance is determined by the type of heater and the type of fuel. For instance, demand heaters are estimated to 8%-34% more efficient than tank heaters, depending on how much water is used per day. A more efficient heater saves you small amounts of money over time, but will almost always cost more up front, and there may be less variety available.