The mixing valve mixs in cold water to the hot water coming out to bring the temp down to where you choose. 140 water never leaves the valve, which is mounted on the exit from the hot water heater. The design is super simple, so failure is very unlikely. But it is designed to fail to full cold.
The mixing valve mixs in cold water to the hot water coming out to bring the temp down to where you choose. 140 water never leaves the valve, which is mounted on the exit from the hot water heater. The design is super simple, so failure is very unlikely. But it is designed to fail to full cold.
I have never heard of a whole home mixing valve. That sounds like it would be a pretty complicated retrofit.