Asked by: Osaro Ruso
asked in category: General Last Updated: 10th January, 2020

What is the O B Wire?

A wire labeled O, B, or O/B is used to control whether a heat pump is in heating or cooling mode. However, on some thermostats, a wire labeled B is the common wire C. In most cases, the common wire is labeled C.

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Similarly, you may ask, what is OB wire on thermostat?

A wire labeled O, B, or O/B is used to control whether a heat pump is in heating or cooling mode. However, on some thermostats, a wire labeled B is the common wire C. In most cases, the common wire is labeled C.

Secondly, is RC the same as C wire? Though it is a common notion, it may be incorrect to state that the C-wire powers the thermostat. Typically, the wires that give the power supply (usually termed as the 'hot' wires) are marked Rc (for cooling) and Rh (for heating). They give a 24-volt power supply from the HVAC system's control panel.

Just so, what color is ob wire?

Terminal designations G – Fan, usually a green wire. R – 24 VAC usually a red wire (Rc and Rh are discussed later) C – 24 VAC Common. Y – Compressor, usually a yellow wire.

What does OB mean on Nest thermostat?

The Nest thermostat defaults to an O orientation for heat. pumps. If the O option is highlighted, select B. If the B option is highlighted, select O. Test your heating and cooling once again to make sure the issue is resolved.

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