Harold Kestenholz
If you are thinking about an instantaneous water heater, there are some shortcomings that have pervented their widespread use in North America. They have difficulty when delivering less than 1/2 gallon per minute because the fire does not turn down to the small demand. The control to do this is a frequent demand for repair or replacement. You will start a 100,000 btuh gas fire to get a pot of hot water for tea. The small diameter tubes lime up in hard water areas, so Europeans typically replace heat exchangers within five years. Europeans also have the manufacturer’s servicemen disassemble, clean, inspect and reassemble the unit yearly.
