MODULATING |
Mode 5 – Outdoor reset using primary/secondary pip- ing. The heater is operated as in Mode 2. However, the target temperature is based on outdoor reset. See Fig. 33.
MODULATING |
*
*Maximum 4 times the pipe diameter or 12”, whichever is less.
Fig. 31: Mode 2 Primary/Secondary Piping
Mode 3 – Dedicated DHW operation using UniTemp 80 piping. A call for heat is determined by the DHW sensor and the DHW boiler target. The heater outlet water is also controlled to the boiler target tempera- ture. See Fig. 32.
MODULATING |
Fig. 32: Mode 3 Dedicated DHW
Mode 4 (Not supported) – Outdoor reset using pri- mary piping. The heater is operated as in Mode 1. However, the target temperature is based on outdoor reset.
*
*Maximum 4 times the pipe diameter or 12”, whichever is less.
Fig. 33: Mode 5 Primary/Secondary Piping with
Outdoor Reset
Mode 6 (Not supported) – Designed for an external input signal with primary piping. The external input sig- nal can be provided from a BMS, an EMS or a sequencing control. The external input signal changes the boiler target according to a linear scale. The con- trol operates the boiler burner to maintain the boiler target at the boiler outlet sensor.
Mode 7 – Designed for an external input signal with primary/secondary piping. The external input signal can be provided from a BMS, an EMS or an external control. The external input signal changes the boiler target according to a linear scale, as shown in Tables O and P. The control operates the boiler burner to maintain the boiler target at the system sensor. See Fig. 34
31
