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Alpha Pressure Switch 1.027277

Alpha

Alpha Pressure Switch 1.027277

At a glance

  • Part type: Pressure switch
  • Also known as 1257404
Manufacturer part no.
1.027277
Showing prices

£30.04

£25.03 ex. VAT · VAT at 20%

Available to order · 3 working days
Available to order · 3 working days
Not certain it's the right part? The technical team verifies fitment before dispatch — no charge, and it stops a second trip.Call the technical teamSend a technical question

Same-day dispatch

Ordered by 4pm Mon–Fri, 10:30am Sat.

30-day returns

Unused, in original packaging.

What it is

The Alpha 1.027277 is a pressure switch used in Alpha domestic gas boilers. It monitors pressure within the appliance and signals the control board when the required condition is met, allowing the boiler to proceed through its ignition sequence and continue running safely. It is a direct replacement component for the Alpha CD and ECO families.

Signs this part needs replacing

  • Boiler locks out during or shortly after the ignition sequence
  • Fan or air pressure fault code displayed on the boiler
  • Intermittent firing, with the boiler starting on some attempts and failing on others
  • Boiler runs briefly then shuts down and repeats the cycle
  • No response from the switch when pressure conditions change, confirmed by meter or continuity testing

Before you order

  • Confirm the model and GC number against the compatibility list, as several Alpha variants use different switch arrangements
  • Check the alternative numbers 1257404 and 027277 against the label on the existing component
  • Isolate the electrical supply before removing the old switch and note the wiring positions
  • Inspect the sensing tube and its connections for blockage, splits or loose fit, as these can mimic a failed switch

Not sure which part?

Search by part number, product name or brand — our technical team confirms fitment before anything is dispatched.