Unigas PBY1025 Manual Of Installation - Use - Maintenance page 106

Connections from terminal side :
24V AC
Probe connection:
input AI1 = probe Pb1 = set-point "tr" = oil heater temperature probe;
input AI2 = probe Pb2 = set-point "tCI" = plant consent temperature probe (when installed);
input AI3 = probe Pb3 = set-point "OIL" = oil heater output temperature probe (PID regulation);
input AI4 = probe Pb4 = set-point "tcn" = oil heater consent temperature probe.
Pb3
Pb4
Pb1
COD. M12924CA Rel. 0.5 03/2016