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Hot water demand indicator on Vaillant Turbomax 242/282 1E

Your boiler is working exactly as it should and is simply confirming that it has received your request to heat water for your tap or shower.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 31 August 2026

What the manual says

Manufacturer manual

The hot water demand indicator will illuminate when a hot tap is turned on and water is drawn at a high rate.

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.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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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 I.003 I.020 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

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