BoilerFaultCodesWhat the manual says
Manufacturer manualSystem pressure too low – the heating system needs venting or water needs topping up until the preset pressure is reached. Replace the cable to the pressure sensor replace the pressure sensor
What causes this fault?
This fault occurs when the internal sensor detects that there is not enough water inside the system to safely transfer heat. The most common cause is a slow leak in the pipework or radiators, though it frequently happens after you have recently bled your radiators to remove air. In some cases, the error persists because the pressure sensor itself has failed or the electrical connection to it has become loose.
This code is frequently seen in autumn when homeowners turn their heating back on for the first time or bleed their radiators to prepare for winter.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Avoid the next call-out bill
A cover plan would handle faults like 2971 B: no call-out fees, no surprise bills.
Affiliate links. We may earn a commission at no extra cost to you.