Patent ID: 8282017

Claim:
A heat transfer system comprising: a first cell ( 46 ) storing liquid and a second cell ( 48 ) storing liquid; a first heating element assembly ( 56 , 66 ) associated with the first cell and a second heating element assembly ( 58 , 68 ) associated with the second cell, wherein said first heating element assembly ( 56 , 66 ) comprises a first tubular coil ( 66 ) situated about a first heating element ( 56 ), said first coil adapted to receive liquid from a heat exchanger ( 14 ) and to heat the received liquid before it is introduced into said first cell ( 46 ) and said second heating element assembly ( 58 , 68 ) comprises a second tubular coil ( 68 ) situated about a second heating element ( 58 ), said second coil adapted to receive liquid from a heat exchanger ( 14 ) and to heat the received liquid before it is introduced into said second cell ( 48 ); a controller ( 22 ) adapted to independently energize each of said heating element assemblies ( 56 , 66 ; 58 , 68 ) when the temperature of liquid in the associated cell is below a first predetermined temperature; and a first pump ( 50 ) adapted to pump liquid from the first cell ( 46 ) to a heat exchanger ( 14 ) and from the heat exchanger to the first cell ( 46 ) via the first coil ( 66 ) and to the second cell ( 48 ) via the second coil ( 68 ), and a second pump ( 52 ) adapted to pump liquid from the second cell ( 48 ) to said first cell ( 46 ) in order to maintain a liquid temperature in said first cell ( 46 ) above a second predetermined temperature, wherein the liquid comprises a heat transfer oil which is liquid at temperatures of 220-250° F. and wherein the heat transfer system comprises a closed flow circuit for the liquid.