Domestic Hot Water Recirculation Control Pilot
FortisBC wanted to evaluate the energy impacts of on-demand recirculation controls and engaged FRESCo to support a pilot project to test Enovative’s technology.
Domestic hot water (“DHW”) recirculation systems in commercial buildings reduce the waiting time that building occupants experience when they make a hot water draw far away from the water heater. Typically, the recirculation pump operates continuously, pumping water from the water heater through a loop that traverses around the entire building and returns to the water heater. The DHW in the loop is maintained at an elevated temperature, resulting in significant heat loss, whether or not there is demand for DHW.
The purpose of demand controls is to operate the recirculation pump only in response to DHW demand. This results in lower temperatures in the DHW loops and less pump operation, leading to a potential 5-20% of natural gas and electricity savings.
How could demand control technology deliver energy savings?
- It reduces water heating gas consumption by eliminating the need to continuously maintain water at high temperatures.
- It reduces electrical usage for pump operation from running 24 hours per day, seven days per week down to approximately six hours per day, reducing.
What are the potential long-term benefits?
- Lowers property operating costs and increases property market value.
- Minimizes pipe occlusion, pinhole leaks and damaging mineral deposits.
- Extends product life of the entire water heating system.
- Compatible technology with solar-thermal water heating systems.