High
H21-049 on Ideal Mini C28

Your boiler's fan is failing to start or maintain the correct speed, which prevents the unit from safely venting exhaust gases and heating your home.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Fan (mod. miniHEC28)

From this model's manual
Verified against the Ideal/Ideal Mini He installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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All 40 fault codes on the Mini C28

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

164-026169-033169-083169-127169-141E00-684E00-688E01E01-156E16E57-048E57-049E69-243E83-013E83-081E83-082E83-086E83-101E83-122E83-126E83-127E83-142E83-145E90-627Faulty air pressure switchFaulty primary circuitH20-986H21-048H21-052H21-060H21-064H27-582Lack of burner ignitionLED 1 fast pulseLED1 flashing, LED2 onLED1 on, LED2 flashingLED2 flashing, LED3 onLock-out signal lamp E blinksOverheat thermostat lockout

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