Fix minor, inaccessible leaks in your central heating system quickly and effectively. This Flume Leak Sealer is designed to seal small weeping joints and hairline cracks, preventing pressure loss in sealed systems and avoiding costly repairs.

The advanced formula forms a soft, flexible seal within 24 hours without causing any blockages in the system. It is suitable for use in all types of central heating systems, including those with aluminium components. For best results and long-term protection, use in conjunction with a system inhibitor.

• Seals minor leaks – quickly seals weeping joints and inaccessible leaks.
• Prevents pressure loss – ideal for maintaining pressure in sealed systems.
• Avoids costly repairs – provides a simple fix for small leaks.
• Broad compatibility – suitable for all systems, including those with aluminium.
• Available in a choice of sizes – including 1L and a 500ml concentrate.

Delivery (UK mainland only)

 

Next Day: £5, or FREE over £40

- Order by 9pm Mon-Thu: next working day

- Order Fri to 5pm Sun: Monday

- Order after 5pm Sun: Tuesday

 

Pre-12pm: £10

- Same cut-offs as Next Day above

 

Saturday & Sunday: £10, or £5 over £40, or FREE over £75

- Saturday: order by 6pm Fri

- Sunday: order by 4pm Sat

 

Heavy items (over 30kg)

- Mon-Fri only. Order by 6pm and allow up to two working days

- Order after 6pm Thu: arrives after the weekend

 

Supplier items

- Sent directly by the supplier, so timings vary. Lead times appear on the product page in working days (Mon-Fri)

 

More about delivery 

Next Business Day Collection (eligible items)

- Order by 9pm Mon-Thu: collect next day

- Order after 9pm Thu to 5pm Sun: collect Monday

- Heavy items (over 30kg): allow up to two working days

 

Opening hours

- Weekdays vary by branch: open 6:30am-7am, close 6pm-8pm

- Saturday: 7am-6pm

- Sunday: 9am-4pm

 

Check your local store's hours and that it's open before visiting. Please wait for our text or email before collecting.

 

Holding your order
We'll hold it for 14 days, then automatically refund your original payment method.