Consider the size of your household and the number of fixtures you have to heat water. Tankless water heating heaters may take some time before the water is heated up enough to allow for showers. Also, pressure can decrease if the temperature rises. Manufacturers will usually give guidance as to how many showers a water heater can power at once. Powering multiple showers is easier with units that have higher GPMs.
Condensing models tend to be more expensive. However, condensing models have a longer lifespan than conventional heaters, which means that you will be able to recuperate the difference in a reasonable time.
Outdoor units have their limits. A propane tankless water heating unit can be used in cold temperatures. However, the heater must be protected from rain, snow, wind, and extreme weather. Also, models made for camping or other offgrid use should not be left out in poor weather.
Concentric venting can be used, or you can opt for horizontal venting at an additional charge. The unit comes with both isolation and pressure relief valves, making annual maintenance flushing easier.
It is important to understand the type of fuel and hot water that you currently use before you purchase a tank water heater. A plumbing contractor will be able to assist you in choosing the best water heater for your home. You can also use A. O. Smith's online Product Selector XPERT(tm).
The cost of the unit is low but it has some great features. A digital thermostat gives you precise temperature control. You can even install it remotely from your unit. Hot start programs reduce water temperature fluctuations which can be caused due to stop/start. Although stainless steel venting is required for this model, which will increase the price, it is still an economically viable option for modest homes or guesthouses.
BTUs (British Thermal Units), is the unit that measures heating power. Technically, it refers to the amount of energy necessary to raise 1 pound worth of water 1° Fahrenheit. In simple terms, the BTU rating can be described as a per-hour value that shows how much heat a tankless hot water heater can produce. This is important because insufficient heat may cause the water to not heat enough.
