Significant loss in pressure High

Heatline Significant loss in pressure Fault Code

Q: What does the Heatline Significant loss in pressure fault code mean?

Your boiler has stopped working because there is not enough water inside the system to operate safely.

Q: How much does it cost to fix Heatline error code Significant loss in pressure?

Typical repair cost for the Heatline Significant loss in pressure fault is £80-150 including labour.

Also written as SIGNIFICANTLOSSINPRESSURE — same fault.

The Heatline Significant loss in pressure fault code means: your boiler has stopped working because there is not enough water inside the system to operate safely.. It appears on 2 Heatline models in our database.

Technical description: The boiler will lock out

Typical repair cost £80-150 (including labour)

DIY fix possible

Locate the filling loop, which is a silver braided hose under your boiler.Open the valves at both ends of the hose to allow water into the system.Watch the pressure gauge on the front of the boiler until the needle reaches the green zone (typically 1.0 to 1.5 bar).Close both valves tightly and remove the filling loop if it is not a permanent fixture.

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Heatline models that show the Significant loss in pressure fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Heatline Significant loss in pressure fault code information on this page is sourced and cross-checked against the official Heatline service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026