Baxi · 600 Combi 2
H.01.21 boiler fault code
600 Combi 2
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Renting? Report it to your landlord or housing provider first. They are responsible for gas safety and boiler repairs, and the repair should not cost you.
What H.01.21 means
H.01.21 indicates Flow temperature rises too quickly in domestic hot water mode; the boiler stops temporarily for 10 minutes.
Safe check
Record the displayed code. Do not open the casing or carry out internal checks; arrange a Gas Safe registered engineer.
When to contact an engineer
Arrange a Gas Safe registered engineer to investigate this boiler fault.
Safety notice
A boiler fault code alone is not a gas or carbon-monoxide emergency. If you smell gas, a CO alarm sounds, anyone feels unwell, or there is an unsafe flame, leave and call 0800 111 999 from outside.
Source and provenance
- Baxi 600 Combi 2 Installation Manual · §11.2, Table 33, printed p. 74
installation manual
Official manufacturer PDF; revision not stated in the supplied citation