231-Series Sump
The HOBBS 231 Series Sumps are located in the pool floor where the piping terminates. The fitting can be utilized for a number of functions: When used as a suction sump, the fitting forces the flow of water over the pool floor, which serves two purposes. First, it prevents vortexing which would otherwise allow air to enter the suction line. This would cause pump cavitation and shorten pump life. Second, it provides better water circulation and improved pool floor cleaning action. The maximum designed flow rate is 60 gallons per minute with a 16" water level. The fitting can also function as a ballast fitting for waterfalls or as a dump line in fountains with a HOBBS #492-Series Wind Compensation System. The maximum flow rate is 70 gallons per minute with a 16" water level. The fitting can also be used as an equalizer fitting between small pools with equal water levels. A maximum flow rate of 20 gallons per minute is possible. As a second function to any of the above, the fitting can function as a small capacity (20 gallons per minute) pool drain. The pipe connections are double tapered to provide leak-free joints from the inside, as well as the outside. This facilitates pressure testing and winterization of the lines and allows draining of the pool by removing a 2" N.P.T. internal plug from the alternate pipe connection, when a separate drain line is installed.