Pool and Spa
Questions about Pool Repair? Ask an Expert Online.
The DR code means there is no water flow through the heater. You may have a pump air lock where air is trapped in pump and you need to loosen the union on front of pump to release air. You may have a bad pump that is not working or a bad pressure/Flow switch located on or next to the heater housing this switch has two wires on it and you need to jump acrioss the two wires to simulate the switch closing and send power to heater. I believe it is the pump that supplies water to heater that is your issue.