11 Electrical - Low Voltage
11.1 Low Voltage Maximum Wire Length
Table 4 defines the maximum total length of low voltage wiring from the outdoor
unit, to the indoor unit, and to the thermostat.
24 Volts - Wire size
18 AWG
16 AWG
14 AWG
Table 4
11.2 Low Voltage Hook-Up Diagrams
Low Voltage Unit Connections
Figure 24
11.3 Thermostat Wiring Diagrams
•
Be sure power supply agrees with equipment nameplate.
•
Power wiring and grounding of equipment must comply with local codes.
•
Low voltage wiring to be No. 18 AWG minimum conductor.
•
"- - - - - - - -" Field installed electric auxiliary heat connection
•
Single-stage auxiliary heating supported by 2H thermostat
•
Twin-stage auxiliary heating supported by 3H thermostat
•
W1: The first stage of field installed electric auxiliary heat.
•
W2: The second stage of field installed electric auxiliary heat.
•
The outdoor unit W signal is connected to the electric auxiliary heat or
the first stage electric auxiliary heat.
Figures 25-30 refer to thermostat wiring diagrams for the BOVA20/
BOVC20 and BVA2.0 manufacturer matched indoor and outdoor
systems.
Bosch IDS BOVA20 & BOVC20 Split System Heat Pump - BTC 761703107 A (12.2023)
Max. Wire Length
150 Ft.
225 Ft.
300 Ft.
Control
Board
Access
Panel
NOTES:
- Low voltage connection must be made inside the
outdoor unit control board access panel.
- There is no terminal block for low voltage connections,
wires must be spliced using field supplied wire nuts
- Field supplied wire nuts should be 22-16 gauge.
- Refer to unit wiring diagram for more information.
Dashed lines in the following thermostat wiring diagrams refer to optional
wiring (wiring for Passive Dehumidification Function and/OR Electric
Heat). For thermostat wiring please refer to the Owner's Manual of the
thermostat.
B terminal to be connected with thermostat (O/B) wiring. Reversing valve
energizes in heating.
Installation Instructions
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