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Sentinel X400 System Restorer 1 Litre

Sentinel

Sentinel X400 System Restorer 1 Litre

Sentinel X400 System Restorer in a 1 litre pack, a liquid treatment for use in heating systems.

Manufacturer part no.
X400
Showing prices

£15.26

£12.72 ex. VAT · VAT at 20%

Available to order · 1-2 working days
Available to order · 1-2 working days
Not certain it's the right part? The technical team verifies fitment before dispatch — no charge, and it stops a second trip.

Same-day dispatch

Ordered by 4pm Mon–Fri, 10:30am Sat.

30-day returns

Unused, in original packaging.

What it is

Sentinel X400 System Restorer is a liquid treatment supplied in a 1 litre pack for use in heating systems. It is manufactured by Sentinel and is intended to restore system condition as part of routine heating system maintenance.

Signs this part needs replacing

  • Radiators heating unevenly, with cold spots at the bottom or across the panel
  • Boiler noise such as kettling, banging or gurgling during operation
  • Sluggish circulation and long warm-up times across the system
  • Discoloured or dirty system water when bleeding radiators or draining down
  • Repeated pump or valve problems linked to system contamination

Before you order

  • Confirm the system volume so the correct quantity of treatment can be calculated
  • Check the system water condition and whether a separate inhibitor is required afterwards
  • Verify the part number X400 against the manufacturer's documentation for your system
  • Check that the treatment is suitable for the materials and components fitted to the system

Not sure which part?

Tell the parts assistant what it's going into — the appliance make and model, or the GC number off the data badge — and it will check this part is on the fit list.