User Manual Marey ECO110 220V Self-Modulating

Both water inlet and outlet connections are 1/2" NPT.

In general, tankless water heaters can work for floor heating applications. There are no specific limitations. However, your design should allow for all of the requirements of this heater, such as the minimum water pressure, which is 8 PSI.

It should. It provides a lot of hot water at the temperature you select. Since it's on-demand and doesn't have a reservoir, it should work well. Keep in mind it's more expensive to operate than a gas fired water heater, but is also instantaneous and convenient to install. Make sure that you run adequately sized conductors and have the proper circuit breakers in your panel

PVC should not be used for the hot water connection. Instead use copper, CPVC, or other high-temperature rated pipe. You may use PVC for the cold water connection.