Rico in Spanish means rich in English just if your talking about money. If your talking about food rico means it's delicious, good, etc. Example, esto huele rico mean this smell good or  que Rica la comida means like delicious food in English. Puerto Rico means Rich Port in Spanish.
Tankless or demand-type water heaters heat water directly without the use of a storage tank. Heat pump water heaters move heat from one place to another instead of generating heat directly for providing hot water. Solar water heaters use the sun's heat to provide hot water.
If your tankless water heater is not installed with isolation valves, it is recommended that you seek the assistance of a plumbing professional.Turn off the electricity and gas, to the tankless water heater. Do not perform this procedure with power or gas turned on; damage to the water heater can occur. Shut off the main water supply valve to the tankless water heater. Consult the instructions provided by the isolation valve manufacturer for specifics in using their valve assemblies.