Isolating a wellbore with a wellbore isolation system

A wellhead sealing assembly comprising:

• a first packer configured to be disposed in a wellhead, wherein the first packer fluidically seals a wellbore providing a first sealing boundary, the first sealing boundary configured to prevent a pressurized fluid from crossing from a first side of the first sealing boundary to a second side of the first sealing boundary;
• a second packer configured to be disposed in a wellhead, wherein the second packer fluidically seals the first packer from an atmosphere of the Earth, providing a second sealing boundary, the second sealing boundary configured to prevent a second pressurized fluid from crossing from a first side of the second sealing boundary to a second side of the second sealing boundary;
• a packer spacer housing configured to mechanically couple the first packer to the second packer, the second packer offset from the first packer;
• and
• a control assembly coupled to the first packer and the second packer, the control assembly configured to:
• sense a wellbore pressure on a bottom surface of the first packer,
• sense a second pressure in a packer cavity defined by the first packer, the second packer, the packer spacer housing, and the wellhead, and
• compare the wellbore pressure to the second pressure to determine that the wellbore is fluidically sealed from the packer cavity.

A method for isolating a wellbore comprising:

• sensing a wellbore pressure on a bottom surface of a first packer, the first packer disposed in a wellhead and configured to provide a first sealing boundary to seal the wellbore, the first sealing boundary configured to prevent a pressurized fluid from crossing from a first side of the first sealing boundary to a second side of the first sealing boundary;
• transmitting a signal representing the wellbore pressure to a controller;
• sensing a second pressure in a packer cavity, the packer cavity defined by a top surface of the first packer, a bottom surface of a second packer disposed in the wellhead and configured provide a second sealing boundary to seal the wellhead, the second sealing boundary configured to prevent a second pressurized fluid from crossing from a first side of the second sealing boundary to a second side of the second sealing boundary;
• transmitting a signal representing the second pressure to the controller;
• comparing the wellbore pressure to the second pressure;
• and
• determining that the wellbore is fluidically sealed from the packer cavity.