Alpha
Alpha differential pressure switch 6.5641850
Genuine Alpha differential pressure switch, part number 6.5641850, fitted from boiler serial number A74708025.
At a glance
- Also known as 1251289
- This is gas appliance work and should be carried out by a Gas Safe registered engineer
£187.58
£156.32 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
This is the differential pressure switch fitted to affected Alpha boilers, monitoring the pressure difference across the fan/flue system to confirm safe combustion airflow before and during firing. It is a genuine Alpha part, number 6.5641850, listed by the manufacturer's own parts records as fitted from boiler serial number A74708025.
Signs this part needs replacing
- Boiler locks out on ignition with a pressure switch or fan-related fault code
- Boiler fails to fire despite the fan running
- Intermittent lockouts that clear on reset
- Switch tests as open/closed incorrectly when checked by an engineer
Before you order
- Check your boiler's serial number against the cutoff quoted (from A74708025) before ordering
- Isolate electrical power to the boiler before working on any controls
- This is gas appliance work and should be carried out by a Gas Safe registered engineer
Compliance
| Alternative numbers | FLOW-SWITCH-PRIMARY, WATER-FLOW-SWITCH-PRIMFUGAS, 1251289 |
|---|
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| ALPHA 500 E | 47-532-07 | 47-532-07 | — | — |
| ALPHA ALPHA 500 E | — | — | — |
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.
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