Method and system for positive evacuation of solar collector

Abstract

A method and system for positive evacuation of water from a solar collector using a bypass line which diverts a portion of water from the feed line of the solar collector to an inlet of a water pump. When the solar water heating circuit is turned off, suction created by the filtration pump rapidly evacuates all or substantially all water present in the solar collector. The system should include a water level switch on the feed line to the solar collector, a drain valve that allows pool water to evacuate from the solar collector and associated piping when water is present, a control mechanism that relays information from the water level switch to the drain valve, a small drain line that connects the solar pool heater feed and return lines to a water pump inlet, and a check valve to prevent by-pass.

1 . A method for positive evacuation of water from a solar collector, comprising
 i) pumping water from a swimming pool through a feed line to a solar collector and back through a return line to said swimming pool during operation of said solar collector;   ii) diverting a portion of pumped water from said feed line so that it bypasses said solar collector and is returned to an inlet of a water pump during operation of said solar collector, thereby creating a bypass flow from said feed line to said water pump;   iii) terminating operation of said solar collector by closing a water inlet to said feed liner; and   iv) positively evacuating water from said solar collector using suction created by said water pump and said bypass flow until substantially all water has been removed from said solar collector.   
     
     
         2 . The method of  claim 1 , wherein a water level sensor located in said feed line is used to determine when substantially all water has been removed from said solar collector. 
     
     
         3 . The method of  claim 1 , further comprising diverting a portion of water exiting from said solar collector via said return line to said swimming pool is diverted from said return line and added to said bypass flow. 
     
     
         4 . A system for positive evacuation of a solar pool heating apparatus, comprising
 a) a water feed line having an inlet and an outlet, and adapted to convey water from a swimming pool to a solar heating apparatus,   b) an inlet valve to open and close said inlet of said water feed line,   c) solar heater control means for opening and closing said inlet valve in response to data received from at least one of a water temperature sensor and a solar energy sensor,   d) a return line having an inlet and an outlet, and adapted to convey water from said solar heating apparatus back to said swimming pool,   e) a solar heating apparatus comprising an intake manifold operatively connected to said outlet of said water feed line and a solar collector panel, and an exhaust manifold operatively connected to said inlet of said return line and said solar panel,   f) a bypass line connecting said water feed line and said return line, said bypass line adapted to convey water from said water feed line and said return line to an inlet of a filtration pump of said swimming pool,   g) a bypass valve located in said bypass line,   h) a water level sensor to indicate whether water is present in said water feed line, said water level sensor being located downstream of said bypass line,   i) bypass valve control means to close and open said bypass valve in response to data received from said water level sensor,   such that a portion of water flowing towards said solar heater apparatus is permitted to flow through said bypass line when said water level sensor indicates water is present in said water feed line.   
     
     
         5 . The system of  claim 4 , wherein said filtration pump is capable of filtering a minimum amount of water equal to four times a volume of said swimming pool within a 24 hour period. 
     
     
         6 . The system of  claim 4 , wherein said inlet valve of said water feed line comprises a three-way motorized ball valve. 
     
     
         7 . The system of  claim 4 , wherein said inlet valve of said water feed line comprises a two-way valve in combination with a booster pump. 
     
     
         8 . The system of  claim 4 , further comprising a gas-fired pool heater. 
     
     
         9 . The system of  claim 4 , further comprising at least one pressure release valve. 
     
     
         10 . The system of  claim 4 , further comprising at least one vacuum relief valve.