Checking hours…Mon–Fri 7:30am–5pm · Sat 9am–12pm01302 279234Trade account
Hanicks
Basket
Sime Expansion Vessel 5112210

Sime

Sime Expansion Vessel 5112210

8 litre expansion vessel with 3/8 inch male connection for Sime Planet DEWY boilers.

At a glance

  • Also known as 2040100
Manufacturer part no.
5112210
Showing prices

£83.00

£69.17 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 Sime 5112210 is an 8 litre expansion vessel with a 3/8 inch male connection. It is fitted to Sime Planet DEWY series gas boilers, where it absorbs the expansion of water as the heating system heats up. This keeps system pressure stable and protects components such as the pressure relief valve from unnecessary discharge.

Signs this part needs replacing

  • Boiler pressure rises quickly when the heating is on, then drops when it cools.
  • Water discharges from the pressure relief valve during heating cycles.
  • Pressure gauge shows low or fluctuating readings with no visible leak elsewhere.
  • Corrosion or water staining around the vessel connection or body.
  • Boiler locks out or requires frequent topping up.

Before you order

  • Confirm your boiler model and GC number against the fit list above.
  • Check the connection size and thread type on the existing vessel.
  • Verify the vessel capacity matches that specified for your appliance.
  • Ensure the fault is with the vessel and not the pressure relief valve or filling loop.

Not sure which part?

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