Alpha
Alpha Flue Limit Thermostat 1.021356
Alpha flue limit thermostat rated at 90°C, part number 1.021356, for Alpha HE and CD series gas boilers.
At a glance
- Also known as THERMOSTAT-SCREW-IN-L90-10C, FLUE-LIMIT-THERMOSTAT-90-C, 1250303
£24.84
£20.70 ex. VAT · VAT at 20%
Same-day dispatch
Ordered by 4pm Mon–Fri, 10:30am Sat.
30-day returns
Unused, in original packaging.
What it is
The Alpha 1.021356 is a flue limit thermostat rated at 90°C, used on Alpha gas boilers in the HE and CD families. It monitors flue temperature and interrupts the boiler's operation when the limit is exceeded, protecting the appliance from overheating and unsafe flue conditions. It is a serviceable thermostat supplied for boiler repair and maintenance work.
Signs this part needs replacing
- Boiler locks out or shuts down shortly after firing
- Repeated resetting required to restore heating or hot water
- Boiler runs briefly then cuts out, with the fault returning each cycle
- Flue limit fault code or lockout indication on the appliance
- No continuity across the thermostat terminals when tested
Before you order
- Confirm your boiler model against the fitment list above
- Check the part number marked on the existing thermostat matches 1.021356
- Verify the 90°C rating matches the component being replaced
- Inspect the wiring and terminal connections before fitting the new thermostat
Compliance
| GC number | H28-385 |
|---|---|
| Alternative numbers | THERMOSTAT-SCREW-IN-L90-10C, FLUE-LIMIT-THERMOSTAT-90-C, 1250303 |
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| ALPHA ALPHA HE CB25 | — | — | — | |
| ALPHA ALPHA HE CB33 | — | — | — | |
| ALPHA ALPHA HE SY25 | — | — | — | |
| ALPHA CD70S | — | — | — | |
| ALPHA CD70S (LPG) | — | — | — | |
| ALPHA HE CB25 | 47-532-25 | 47-532-25 | — | — |
| ALPHA HE CB25 (LPG) | 47-532-27 | 47-532-27 | — | — |
| ALPHA HE CB33 | 47-532-26 | 47-532-26 | — | — |
| ALPHA HE CB33 (LPG) | 47-532-44 | 47-532-44 | — | — |
| ALPHA HE SY25 | 41-532-07 | 41-532-07 | — | — |
Showing 10 of 15 compatible appliances.
Documents & drawings
Everything we hold for this part. Where a document exists but we don't hold it, the technical team will source it from the manufacturer — usually the same working day.
ALPHA appliance manual — CD70S, CD70S (LPG)
manualmanualALPHA appliance manual — HE CB25 (GC 47-532-25), HE CB25 (LPG) (GC 47-532-27), HE CB33 (GC 47-532-26), HE CB33 (LPG) (GC 47-532-44), HE SY25 (GC 41-532-07), HE SY25 (LPG) (GC 41-532-12)
manualmanualALPHA appliance manual — HE25 (GC 47-532-41), HE25 (LPG) (GC 47-532-42), HE33 (GC 47-532-43), HE33 (LPG) (GC 47-532-44)
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