Upon arrival, the customer reported that their boiler would not turn on. While inspecting the equipment in the basement, I noted that the low-water cutoff was repeatedly clicking. I confirmed that it was receiving proper line voltage in and out as expected. I then traced power entering the boiler control and found that although 120 V was present on the input, there was no consistent output. At times, the control produced no voltage, and at other times it delivered intermittent, low voltage. I checked the resistance on the outdoor sensor and found it reading open line (OL). Next, I removed the primary control from the burner and discovered that it had shorted against the burner tube. After contacting technical support, we reviewed the sequence of events and agreed that this short likely caused failure of the boiler control. The existing control is over 30 years old and is no longer readily available. I attempted to reach tech support again to determine whether a retrofit control is poss
