When installing the Smart Thermostatic Control in a home without a dedicated recirculation loop there is always the question, “how many thermostatic crossover valves do I need and where should they be installed?”
The simple answer is you need one AMK-ODR valve
at the end of each dead-end hot water line. However, if you don’t have a plumbing schematic for your home this may not be a simple answer.
The way to figure out how many dead-end hot water lines you have is to wait for the hot water lines to cool off. Then go to the sink in your home that takes the longest time to heat up. Run the hot water at this location until the water is hot.
Now go to all the other sinks in your home and see if they have hot water in them. If the water is hot within seconds, then it is on the same line. If it doesn’t heat up quickly then it is probably on a separate line and will need a second AMK-ODR valve.
Many homes have a line that services the bathrooms in one direction and a second line that services the kitchen, but that is just a generalization. And depending on the location of the water heater relative to the hot water fixtures, an AMK-ODR valve may not be necessary on some hot water lines. For example, if the water heater is located in the garage adjacent to the kitchen or laundry room then a valve at that location is probably not needed because it will have hot water quickly already.
Tip for Large Houses and Better Performance
Another reason to install an additional valve is if you have a large house. The AMD-ODR valves have the highest flow of any thermostatic valve on the market, but they still restrict the pump flow.
If you have two bathrooms that are near each other and on the same line but far from the water heater, installing one at each location will allow twice the water flow thus speeding up your on-demand hot water performance.
It can take a few cycles to get an understanding of your plumbing layout especially if your home has had an addition, but this method should give you a good understanding of how hot water flows in your home.
If you have any questions or need advice, contact customer support, we love to help.