Checking hours…Mon–Fri 7:30am–5pm · Sat 9am–12pm01302 279234Trade account
Worcester Bosch O-Ring Retainer Pump 87186844700

Worcester Bosch

Worcester Bosch O-Ring Retainer Pump 87186844700

O-ring for the pump retainer on Worcester Bosch Greenstar Compact and Heatslave II boilers.

At a glance

  • Also known as 1031403
Manufacturer part no.
87186844700
Showing prices

£14.32

£11.93 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 O-ring retainer pump is a sealing component used on the pump retainer assembly of Worcester Bosch gas boilers. It is manufactured by Worcester Bosch under part number 87186844700 and forms part of the pump sealing arrangement on the Greenstar Compact and Heatslave II appliance families. Its role is to seal the pump retainer joint and prevent water loss from the circulating pump.

Signs this part needs replacing

  • Water weeping or dripping from the pump retainer joint
  • Visible perishing, flattening or cracking of the O-ring
  • Scale or corrosion build-up around the pump retainer seating
  • Loss of system pressure with no other obvious source
  • Evidence of a previous leak, such as staining or residue at the pump housing

Before you order

  • Confirm the boiler model and GC number against the fitment list above
  • Check the part number 87186844700 matches the component being removed
  • Inspect the pump retainer and housing for damage before refitting
  • Confirm whether any additional seals or gaskets are required for the same repair

Not sure which part?

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