Insufficient system pressure Sufficient water pressure is not detected within the heating circuit to guarantee correct operation of the boiler Check on the boiler pressure gauge (23) that the system pressure is between 1÷1.2 bar (17.4 psi)
The 10 error code on Immergas boilers indicates insufficient system pressure sufficient water pressure is not detected within the heating circuit to guarantee correct operation of the boiler check on the boiler pressure gauge (23) that the system pressure is between 1÷1.2 bar (17.4 psi).
Immergas 10 means: insufficient system pressure sufficient water pressure is not detected within the heating circuit to guarantee correct operation of the boiler check on the boiler pressure gauge (23) that the system pressure is between 1÷1.2 bar (17.4 psi). On this component the documented failure modes are sufficient water pressure is not detected within the heating circuit to guarantee correct operation of the boiler or system water pressure too low, or a leak somewhere in the system. You can safely reset the boiler once — if 10 returns, do not keep resetting. A qualified heating engineer should diagnose the root cause.
What Does 10 Mean
The 10 code is shown by the boiler’s control board when it detects insufficient system pressure sufficient water pressure is not detected within the heating circuit to guarantee correct operation of the boiler check on the boiler pressure gauge (23) that the system pressure is between 1÷1.2 bar (17.4 psi). The boiler then stops instead of continuing to run in that condition: the code is the appliance reporting a problem, not proof that the boiler is broken.
| What you see on the boiler |
|---|
| The display shows 10 and the boiler stops until the fault is cleared |
Common Causes
The first cause below is the one the Immergas service literature publishes for this code (source: centriassistenza.org). The others are the failure modes documented for the same component on other boilers, confirmed by 5 different manufacturers.
| Cause |
|---|
| Sufficient water pressure is not detected within the heating circuit to guarantee correct operation of the boiler |
| System water pressure too low, or a leak somewhere in the system |
Safety Warning
10 involves electrical or pressure-related components. Do not attempt repairs without proper qualifications. Ensure the boiler is electrically isolated before any inspection. If you notice water leaks, unusual sounds, or pressure anomalies, contact a qualified heating engineer immediately.
Parts & Prices
Prices shown are indicative. Actual prices and availability vary by region.
How to Fix It
Check on the boiler pressure gauge that the system pressure is between 1÷1.2 bar (17.4 psi) and restore the correct pressure if necessary
Check on the boiler pressure gauge that the system pressure is between 1÷1.2 bar (17.4 psi) and, if necessary, restore the correct pressure
Check on the appliance pressure gauge that the system pressure is between 1÷1.2 bar (17.4 psi) and, if necessary, restore the correct pressure
Repressurise the system to the pressure stated on the boiler — typically 1.0–1.5 bar (15–22 psi) when cold. If it drops again, look for a leak on pipework, radiator valves and the pressure relief discharge.
Refer to the Immergas service documentation for the detailed procedure. Only a qualified engineer should carry out these repairs.
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Affected Models
Immergas models that can display fault code 10:
| Model Family | Output Range | Frequency |
|---|---|---|
| All Immergas models | — | Possible |
Frequently Asked Questions
Check on the boiler pressure gauge that the system pressure is between 1÷1.2 bar (17.4 psi) and restore the correct pressure if necessary. According to the technical documentation, this is the first check on the list for 10.
10 is not classified as a high-severity fault, so the boiler can be reset once. If 10 comes back, stop resetting: the underlying cause is still there and needs a qualified heating engineer.