Required if the boiler or the combi boiler does not have control of the pump
Optional: 'G' for fan-only operation and 'C' for t-stat common
Dry contact from the air handler to the boiler or combi boiler that enables a call for heat
The reversing valve operation is selectable with the AHU app: the default setting
energizes the O/B terminal during cooling
Required: the outdoor sensor for balance point control of backup heat source is available
separately as IBC outdoor sensor kit P-9067.
Required: sensors for cooling applications are available separately as IBC A/C sensor kit
P-1015
Required: if outdoor unit requires a dry contact; typical of bonded controls. Check your
outdoor unit installation manual.
Figure 35 Single-stage heat pump with a boiler or combi boiler as backup wiring - with isolation relays
Worked examples:
1. Wiring single-stage heating with a boiler or combi boiler on page 37
2. Wiring single-stage heating with a tankless water heater as a heat source on page 38
3. Wiring single-stage heating with boiler or combi boiler, and single-stage cooling on page 39
4. Wiring two-stage cooling with a boiler or combi boiler heating using a 2-stage thermostat on
page 40
5. Wiring single-stage heat pump with a boiler or combi boiler as backup on page 41
6. Wiring single-stage heat pump with a boiler or combi boiler as backup (emergency heat on
T-stat) on page 43
7. Wiring two-stage heat pump with a boiler or combi boiler as backup (2-stage thermostat) on
page 45
8. Wiring two-stage heat pump (2-stage thermostat) on page 47
9. Wiring single-stage heating, single-stage cooling, with the tankless water heater as the
heat source on page 48
10. Wiring two-stage cooling with a tankless water heater as a heat source on page 49
11. Wiring single-stage heat pump with a tankless water heater as a backup on page 50
12. Wiring two-stage heat pump with a tankless water heater as a backup on page 52
13. Wiring make-up air with a boiler or a combi as a heat source on page 54
2.8.0.1 Tankless Mode
Tankless Mode should always and only be chosen when a tankless water heater is a heat source.
Tankless mode recognizes that when DHW is being drawn the water heater is in effect temporarily
unavailable, so reduces the fan speed when outlet temperature drops.
To Next Page
Loading...
Need help?
General
