What does the Heatline d.08 fault code mean?

This code is simply an indicator showing that your room thermostat is currently sending a signal to the boiler to request heating.

How much does it cost to fix Heatline error code d.08?

Cost varies. Contact a Gas Safe registered engineer for a quote.

Heatline d.08 Fault Code: What It Means & How to Fix It

What the manual says

Manufacturer manual

Current state of the 230V room thermostat

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

Check your wall-mounted room thermostat settings to ensure it is set to your desired temperature.If the boiler is running when you do not want it to, lower the temperature setting on your thermostat.If the code persists when the heating is turned off, consult your thermostat manual to ensure it is wired and communicating correctly.

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All 118 fault codes on the Vizo 24

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

d.00 d.01 d.02 d.09 d.10 d.16 d.17 d.18 d.20 d.22 d.23 d.33 d.34 d.35 d.36 d.40 d.41 d.44 d.67 d.68 d.69 d.71 d.80 d.81 d.82 d.83 d.85 d.93 d.94 d.96 Err F00 F0 F01 F1 F2 F3 F4 F5 F6 F10 F11 F20 F22 F23 F24 F26 F27 F28 F29 F32 F49 F61 F62 F63 F64 F65 F67 F68 F70 F71 F72 F73 F74 F76 F77 F83 F84 F85 F86 P.01 P.02 P.03 P.05 P.06 P.07 S.00 S.01 S.02 S.03 S.04 S.05 S.06 S.07 S.08 S.10 S.11 S.13 S.14 S.15 S.16 S.17 S.20 S.21 S.23 S.24 S.25 S.26 S.27 S.28 S.30 S.31 S.32 S.34 S.35 S.36 S.37 S.41 S.53 S.54 S.58 S.90 S.92 S.95 S.96 S.97 S.98

This code is simply an indicator showing that your room thermostat is currently sending a signal to the boiler to request heating.

What the manual says

DIY fix possible

Avoid the next call-out bill

All 118 fault codes on the Vizo 24

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