Too high difference between two CH supply water temperature sensors.
When the system measures a difference between two CH supply water temperature sensors equal or higher than 18ºF ( with a confirming time of 10 seconds), error 52 is created. This error condition is stopping the boiler and to get to the normal operation again, the temperature between the two CH supply water temperature sensors has to be lower than 14°F for 10 seconds. When this timer is expired, error will be resolved.
