Some small-capacity water-cooled refrigeration systems use municipal water as their cooling medium. These systems will typically add a regulator to control water flow through the condenser. These regulators are commonly referred to as water regulating valves. They serve two purposes: They regulate water flow to maintain the system’s high-side pressure and stop the flow of water when the system cycles off so as not to waste water.
These valves can also be used on larger systems using a water tower instead of municipal water. In those designs, it is generally best to use a three-way water regulator. They have an additional port to bypass the water around the condenser as the port that controls water flow to the condenser closes.
The system’s high-side pressure is exposed to the underside of the regulator’s diaphragm. As the condenser pressure increases, the diaphragm flexes, and, through a mechanical linkage, opens the valve to let more water flow through. As the condenser pressure decreases, less pressure is applied to the underside of the diaphragm and an opposing spring on the opposite side of the diaphragm closes the water valve. The spring pressure and the high-side pressure oppose one another to balance the correct amount of water flow through the valve. When the system shuts down, the high-side pressure is too low to oppose the spring pressure and the regulator completely shuts down.