Rinnai Wireless Controller The Rinnai Wireless Controller (with transceiver) is the easiest and quickest to install, and suitable for retrofitting into existing homes. No need to mix hot and cold water, this reduces temperature spiking when another tap in the building is turned on Allows diagnosis of problems (such as gas supply disruption) when the appliance is serviced by displaying 'error' codes, which the service person can utilize. Safety, especially if you have young children, the hot water can be pre-set to a child-safe level.