The Tekmar Differential Setpoint Solar Control 156 is designed to operate an on - off pump to transfer heat from a heat source like solar panels to a storage tank. The Tekmar 156 is perfect control for most basic solar hot water heating applications but can also be a part of a more elaborate solar system. The Tekmar 156 control operates based on a setpoint temperature difference or delta T. The relay turns on when the delta T rises above the setpoint and turns off when the delta T falls below the setpoint less the differential. The Source Minimum and Storage Maximum settings turn off the relay when heat transfer is no longer desirable. Some of the potential applications of the Tekmar 156 control include using solar hot water collectors or a wood boiler as a heat source. Included with this control is two Tekmar 071 Sensors which are 3/8 inch OD and 3/4 inch long. Some Solar Panel and Solar Storage Tanks have smaller wells and may require the purchase of Tekmar 079 Sensors.
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Product Spec Sheet