9 Outdoor DC fan motor fault
The F8 error code on Haier boilers indicates 9 outdoor dc fan motor fault.
Haier F8 means: 9 outdoor dc fan motor fault. The usual causes are fan motor failure (seized bearings or burned windings), fan speed sensor fault or wiring fault between fan and pcb. You can safely reset the boiler once — if F8 returns, do not keep resetting. A qualified heating engineer should diagnose the root cause.
What Does F8 Mean
The F8 code is shown by the boiler’s control board when it detects 9 outdoor dc fan motor fault. 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 F8 and the boiler stops until the fault is cleared |
Common Causes
Causes documented in 1 technical sources.
| Cause |
|---|
| Fan motor failure (seized bearings or burned windings) |
| fan speed sensor fault |
| wiring fault between fan and PCB |
| air pressure switch fault (stuck open or closed) |
| blocked flue or air intake restricting airflow |
| condensate blocking the siphon or trap |
Safety Warning
F8 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.
Step-by-Step Diagnosis
Listen for the fan — it should start before ignition. If silent, check power supply to the fan motor
Spin the fan manually (with power off) — if it feels stiff or gritty, the bearings are worn
Check the wiring connections between the fan and PCB
Test the air pressure switch — with the fan running, the switch should close. Disconnect and test with a multimeter for continuity
Check the flue for blockages — inspect the full length including the terminal
Verify the condensate trap is clear
Measure the fan speed signal at the PCB (Hall sensor output)
How to Fix It
Replace the faulty thermistor/NTC sensor
repair or replace damaged wiring
clean corroded connectors
if the PCB input is damaged, replace the PCB
Refer to the Haier service documentation for the detailed procedure. Only a qualified engineer should carry out these repairs.
Diagnostic Tools
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Affected Models
Haier models that can display fault code F8:
| Model Family | Output Range | Frequency |
|---|---|---|
| All Haier models | — | Possible |
Frequently Asked Questions
Replace the faulty thermistor/NTC sensor. According to the technical documentation, this is the first check on the list for F8.
F8 is not classified as a high-severity fault, so the boiler can be reset once. If F8 comes back, stop resetting: the underlying cause is still there and needs a qualified heating engineer.