Recirculation Pumps – What Is A Hot Water Re-circulation System?
Are you waiting at your sink or shower for the water to get hot? In a standard home, when a hot water valve is opened, the water in the hot water pipe has usually been sitting in the pipe for a while and is no longer hot. Anyone needing hot water turns the faucet on and waits until hot water from the water heater tank reaches the fixture. In large homes, especially at the plumbing fixtures farthest from the water heater, this can take a while and the water running in the meantime is wasted.
Hot water recirculation systems circulate water in the hot water pipes, so that hot water will always be available and less water is wasted. This causes the water heater to run more, but how much more depends on the type of system. If the home uses a solar water heating system, this is less of a concern, since heating water is inexpensive or free.
What Is A Hot Water Recirculation Under-sink System?
This system is typically used on retrofits but may also be installed in new construction. A pump is installed under the bathroom sink farthest from the water heater. The pump contains a sensor which switches the pump on when water temperature drops below 85°F and switches it off when water temperature reaches 95°F. Newer pumps are adjustable from 77° to 104°.
In this system hot water is re-circulated intermittently. Hot water is returned to the water heater via the cold water pipes. This raises the temperature of the cold water slightly, but it returns to the usual cold temperature in a short time.
Hot Water Recirculation System Installed At The Water Heater
This system can deliver hot water to fixtures quickly without waiting for the water to get hot. Rather than relying on low water pressure common in most water lines, recirculating systems use a pump to rapidly move water from a water heater to the fixtures. The system circulates water back to the hot water storage so that it’s ready the moment you turn on the tap. The pump uses the main supply line, which eliminates the need to install a return line. A small circulation pump is installed on the outlet pipe of the hot water storage tank to ensure the water in your line stays hot. The valve at your tap provides the by-pass that allows the water to recirculate using the already installed cold water pipe line as a return line to the hot water service. Together the pump and valve provide instant hot water from every tap and shower in the home. There is even a timer on the pump to make the system even more efficient during low-demand periods like night and midday.