Code 32, furnace locks out, pressure gauge may show high reading

Safety: Allow the system to cool. High pressure can cause hot water discharge.

• Check gauge: Confirm the pressure reading. Anything significantly above the recommended maximum (often 2.5–3.0 bar) is too high.
• Release pressure: Bleed a small amount of water from a radiator bleed valve or drain point into a container until pressure returns to normal.
• Check filling loop: Ensure both filling loop valves are fully closed and the hose is removed if required by local regulations.
• Expansion vessel check: If pressure rises sharply when heating, the expansion vessel may be flat or failed. A technician should test and recharge or replace it.