Received a series of text messages / emails from our Waterfurnace 7 this AM, started with “Main System in Tennessee Ridge, TN has experienced an E16: "Variable Speed Pump" on Nov 20, 2023 at 10:21 AM.” System looked like it was running normally, loop pump power was about 260W per Symphony. Cycled the circuit breakers, error returned once system restarted. Error repeated 5X over the next 25 minutes, then the system sent an E5: “Main System in Tennessee Ridge, TN has experienced an E5: "Freeze Detection - Coax" on Nov 20, 2023 at 10:53 AM.” and shut down. Current state: - Backlights are off on all the thermostats - All lights are off on the Intellezone2 controller (however I measured 27VAC on its power terminals) - No sounds like the blower or loop pump from the unit - Green light on the surge suppressor on the front of the unit is lit - No response from Symphony Unit was in heat mode when this happened. Did the loop pump fail, coolant got too cold and the unit went into a protect mode? I Emailed our dealer / servicer when this happened (plus they should be getting the messages), no response. Had an all day Dr appt, was unable to call. Any thoughts / suggestions? Unit was commissioned in 2018, received a PM this April, first real problem.