What does the Vaillant I.020 fault code mean?

Your boiler has detected that the water level in your heating system has dropped slightly below the recommended amount.

How much does it cost to fix Vaillant error code I.020?

Typical repair cost for the Vaillant I.020 fault is £0-£90 including labour.

Vaillant I.020 Fault Code: What It Means & How to Fix It

What the manual says

Manufacturer manual

The water pressure in the heating system is at the lower limit.

Shared across the range

This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.

DIY fix possible

Locate the external filling loop, which is a silver braided hose usually underneath the boiler.Open the small valves at either end of the loop slowly until you hear the water flowing.Watch the pressure gauge on the front of the boiler and close the valves once the needle reaches 1.5 bar.

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All 172 fault codes on the Turbomax 242/282 1E

Seeing a different code? Every code this model can display, in one place.

Burner lock out indicator F.000 F.001 F.002 F.003 F.010 F.011 F.012 F.013 F.020 F.022 F.023 F.024 F.025 F.027 F.028 F.029 F.032 F.035 F.040 F.042 F.044 F.047 F.049 F.057 F.061 F.062 F.063 F.064 F.065 F.067 F.068 F.070 F.071 F.072 F.074 F.075 F.076 F.077 F.078 F.080 F.081 F.083 F.084 F.085 F.087 F.088 F.089 F.090 F.092 F.095 F.096 F.097 F.105 F.194 F.195 F.196 F.317 F.318 F.320 F.321 F.322 F.323 F.324 F.325 F.326 F.327 F.330 F.334 F.336 F.337 F.338 F.342 F.343 F.344 F.347 F.363 F.707 F.905 Fan operation indicator Flame indicator Hot water demand indicator I.003 I.144 Ignition indicator L.016 L.022 L.025 L.032 L.095 L.096 L.097 L.105 L.144 L.194 L.195 L.196 L.319 L.320 L.322 L.343 N.013 N.027 N.032 N.089 N.095 N.096 N.097 N.100 N.144 N.194 N.270 N.317 N.319 N.324 N.343 Power on indicator S.000 S.001 S.002 S.003 S.004 S.005 S.006 S.007 S.008 S.009 S.010 S.011 S.012 S.013 S.014 S.015 S.016 S.017 S.019 S.020 S.021 S.022 S.023 S.024 S.025 S.026 S.027 S.028 S.029 S.030 S.031 S.032 S.034 S.039 S.041 S.042 S.054 S.057 S.059 S.088 S.091 S.092 S.093 S.096 S.097 S.098 S.109 S.175 S.199 S.326 S.328 S.335 S.341 S.599

Your boiler has detected that the water level in your heating system has dropped slightly below the recommended amount.

What the manual says

DIY fix possible

Avoid the next call-out bill

All 172 fault codes on the Turbomax 242/282 1E

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