Alpha
Alpha Air Pressure Switch 1.8396
Air pressure switch for Alpha CB24, CB24X, CB28, CB28X and SY24 LPG boilers, part number 1.8396.
£87.24
£72.70 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 air pressure switch is an Alpha component fitted to CB and SY series LPG boilers. It monitors the pressure produced by the combustion fan and confirms that air is moving through the appliance before the gas valve is allowed to open. If the switch does not prove airflow, the boiler will not fire and will typically lock out.
Signs this part needs replacing
- The fan runs but the boiler fails to ignite and goes to lockout
- Repeated or intermittent lockout on start-up or during a demand for heat
- Boiler fires only when the pressure switch tubing is disturbed or re-seated
- No continuity across the switch when the fan is running and airflow is proven
- Lockout clears on reset but returns on the next cycle
Before you order
- Confirm your boiler model against the fit list above, as this switch is listed for LPG variants
- Check the part number on the existing switch matches 1.8396
- Inspect the sensing tubes and fan for blockage or damage before assuming the switch has failed
- Verify the appliance is the LPG version, as the natural gas models are not listed here
No specification data held for this part.
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| ALPHA ALPHA CB24 | — | — | — | |
| ALPHA ALPHA CB24X | — | — | — | |
| ALPHA ALPHA CB28 | — | — | — | |
| ALPHA ALPHA CB28X | — | — | — | |
| ALPHA ALPHA SY24 | — | — | — | |
| ALPHA CB24 | 47-532-15 | 47-532-15 | — | — |
| ALPHA CB24 (LPG) | — | — | — | |
| ALPHA CB24X | 47-532-14 | 47-532-14 | — | — |
| ALPHA CB24X (LPG) | — | — | — | |
| ALPHA CB28 | 47-532-16 | 47-532-16 | — | — |
Showing 10 of 15 compatible appliances.
Documents & drawings
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