What we do on site
We start with the code and a flow check, because a lot of heater calls are a filter or valve problem showing up as a heater fault. Then we test the part the code points to. Ignitors, sensors, switches and boards are the usual fixes.
On older heaters we check the exchanger. Conejo Valley water is hard, and scale builds up inside the tubes until the heater can't move heat into the water.
