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F4 Central Heating Leak Sealer 844300

GBP £21.99
44 points

Free Collection in store.
Free Collection in store.
Home delivery within 3 days
Home delivery within 3 days
Express delivery also available
Check stock in your area Check stock in your area

Product details

  • This F4 Central Heating Leak Sealer can be used to repair small leaks and weeps in sealed systems without blocking pumps.
  • Features: Easy to use, seals most small leaks.
  • Material: Non Hazardous.
  • Usage: One bottle is sufficient to treat up to 10 single radiators.
  • Compatibility: Not for use in single feed indirect cylinders. Compatible with all metals including aluminium.
  • Installation: For open vented systems, add via the header tank. For sealed systems, add via a filling loop or via the radiator using a Fernox injector.
  • VOC level: Low.
  • Quantity in pack: 1.
  • WRAS approved: BS EN ISO 9001 and 14001.
  • Safety details: F4 Leak Sealer is not classed as hazardous, but as with all chemicals, care should be taken.
  • Caveat: If in doubt, consult a competent plumber.

Delivery Information

All delivery methods displayed on the product page are estimated subject to stock and your delivery address.

We are able to deliver most orders to mainland UK and Northern Ireland addresses. Delivery of some items to Northern Ireland may take a little longer than stated above. Unfortunately, we are unable to deliver to the following areas; Channel Islands, Isle of Man, Isle of Wight, Orkney Islands, Shetland Islands, Scottish Islands, BFPO addresses and the Republic of Ireland.​

Available delivery options are confirmed during the checkout for you to select. Options offered may vary for orders containing multiple products.

Home delivery – From £3.95

Standard delivery including Saturday

  • Small items (one delivery person): usually within 3 days – £3.95
    (No signature required. You can add delivery instructions at checkout e.g. leave with neighbour)
  • Larger items (two delivery people): from 7 days – £8.95

Please note: some appliances are available with an express delivery service which is usually within 2 days – £19.99. These items include the cost of delivery within the product price and this will be stated on the product page.

Collect in store - Free

Reserve & Collect

  • Check stock in a store of your choice and reserve to collect and pay in store.
  • We'll contact you to confirm your reservation and when your item[s] are ready to collect, usually 3 hours after placing your reservation (during store opening hours). Your item[s] will be reserved until the store closes on the next working day.

Pay now & Collect

  • Pay now to order into a store on a day of your choice
  • Order by 2pm for delivery to store next working day

For more information about our delivery services, please visit our delivery information page delivery information page

Returns Information

Free returns - Please see our returns and refunds policy.

*Restricted delivery dates will be available during bank holiday periods