Product Description

Fernox LS-X External Leak Sealer and Jointing Compound 50ml

Product Code: 61016

Seal suitable external leaks and plumbing joints with Fernox LS-X External Leak Sealer and Jointing Compound. This ready-to-use silicone paste works on hot and cold water services, including suitable potable-water applications.

Fernox LS-X is ideal for compression joints and threaded fittings. In addition, it remains flexible instead of setting rock hard. Therefore, you can undo the joint more easily when future maintenance becomes necessary.

The compound comes ready to use in a convenient 50ml tube. It requires no mixing and does not shrink or crack as it ages.

Key Features

• Fast-acting external leak sealer
• Ready-to-use silicone jointing compound
• Supplied in a convenient 50ml tube
• Ideal for compression joints
• Suitable for threaded and screwed fittings
• Suitable for hot and cold water services
• Suitable for approved potable-water applications
• WRAS-approved product
• Requires no mixing before use
• Does not set rock hard
• Allows joints to be undone during future maintenance
• Does not shrink or crack with age
• Suitable for temperatures below freezing and above the boiling point of water
• Easy to apply directly from the tube
• Product code: 61016

Fernox LS-X Specification

• Download the Fernox LS-X Data Sheet
• Download the Fernox LS-X Safety Data Sheet
• Brand: Fernox
• Product: LS-X External Leak Sealer
• Product type: external leak sealer and jointing compound
• Pack size: 50ml
• Form: silicone paste
• Colour: milky white
• Odour: mild acetic
• Ready to use: yes
• Mixing required: no
• Potable-water use: suitable for approved applications
• Approval: WRAS approved
• Product code: 61016

What Is Included?

• 1 x 50ml tube of Fernox LS-X External Leak Sealer
• Product instructions and safety information shown on the packaging

Suitable Applications

Fernox LS-X provides a practical solution for several common plumbing jobs. For example, you can use it on suitable:

• Compression joints
• Threaded plumbing fittings
• Screwed fittings
• Hot-water pipework
• Cold-water pipework
• Potable-water services
• External pipe and fitting leaks
• General plumbing maintenance and repairs

Always confirm that the product suits the pipe, fitting, water temperature and operating pressure before application.

Flexible Jointing Compound

Some jointing compounds become extremely hard after curing. However, Fernox LS-X remains flexible and does not set rock hard.

As a result, it helps seal the joint while still allowing an installer to undo the fitting during future repairs or maintenance. It also resists shrinking and cracking as it ages.

How to Use Fernox LS-X

1. First, switch off or isolate the relevant water supply.
2. Relieve the water pressure before starting whenever possible.
3. Drain the system if necessary while the compound sets.
4. Clean the application area and remove loose dirt or residue.
5. Apply Fernox LS-X directly from the tube.
6. Shape the compound with a spatula or suitable knife.
7. Dip the tool into soapy water first to reduce sticking and dragging.
8. Replace the tube cap immediately after use.
9. Allow a minimum of two hours for the compound to set.
10. Allow more time where you have applied a thicker layer.

Moisture supports the curing process. Therefore, lightly spraying the applied compound with water can help it cure more quickly.

Repairing Larger External Leaks

Fernox LS-X can seal suitable external leaks. However, larger leaks and systems operating at higher pressures may require reinforcing material.

First, remove the water pressure and dry the area. Next, apply LS-X around the leak. Then use suitable reinforcement tape or fibre where required. Apply further compound to form a secure repair and allow it to cure fully before restoring the system.

Always follow the latest Fernox instructions. Also replace any damaged pipe or fitting where a permanent mechanical repair provides the safer solution.

Setting and Curing Time

Allow Fernox LS-X to set for at least two hours. However, thicker applications may need more time.

Water or atmospheric moisture helps the silicone cure. Therefore, a light spray of water may speed up the process. Do not restore the system until the compound has cured sufficiently for the application.

Potable-Water Use and WRAS Approval

Fernox designed LS-X for hot and cold water services, including approved potable-water applications. The product also carries WRAS approval.

However, WRAS approval applies under the stated approval and curing conditions. Therefore, always follow the latest Fernox data sheet, WRAS approval details and application instructions when using the product on drinking-water systems.

Safety and Handling

• Read the product label before use
• Check the latest safety data sheet
• Keep the product away from children
• Avoid contact with skin and eyes
• Use the compound in a well-ventilated area
• Replace the cap immediately after application
• Store the tube according to the manufacturer’s instructions
• Do not use the product for an application not approved by Fernox

If the product enters your eyes or causes skin irritation, follow the first-aid guidance in the current safety data sheet.

Why Choose Fernox LS-X?

Fernox LS-X combines leak-sealing performance with the convenience of a ready-to-use paste. It works on common plumbing joints and does not require mixing. Furthermore, it remains flexible, so installers can undo treated joints during future maintenance.

The compact 50ml tube also fits easily into a plumber’s toolbox. Therefore, it provides a useful solution for professional installers, maintenance teams and suitable domestic plumbing repairs.

Why Buy from SNH Tradecentre?

• Independent plumbing and heating merchant
• Established family-run business
• Helpful technical product information
• Fast UK delivery options
• Collection available from our Birchington trade counter
• Secure online ordering
• Support before and after your purchase
• Fernox plumbing products available from one trusted supplier

SNH Tradecentre supplies professional plumbing, heating and maintenance products to trade and public customers. Therefore, our team can help you check product suitability and find related plumbing components before you order.

Frequently Asked Questions

What is Fernox LS-X?

Fernox LS-X is a ready-to-use silicone paste that works as an external leak sealer and plumbing jointing compound.

What size tube is supplied?

This product comes in a 50ml tube.

Can I use Fernox LS-X on compression fittings?

Yes. Fernox recommends LS-X for suitable compression joints and screwed fittings.

Can I use it on hot and cold water pipes?

Yes. Fernox designed LS-X for suitable hot and cold water services.

Is Fernox LS-X suitable for drinking water?

Fernox lists LS-X for approved potable-water applications. It also carries WRAS approval. However, you must follow the stated application and curing conditions.

Does Fernox LS-X set completely hard?

No. The compound does not set rock hard. Therefore, you can normally undo the treated joint more easily during future maintenance.

Does it need mixing?

No. Fernox LS-X comes ready to use directly from the tube.

How long does Fernox LS-X take to set?

Allow at least two hours. However, thicker applications may require a longer curing period.

Can I use it while the pipe remains under pressure?

You should relieve the water pressure before application whenever possible. Drain the system where necessary while the compound sets.

Can Fernox LS-X repair every leaking pipe?

No. It suits certain external leaks and joints. Larger leaks, high-pressure applications or damaged pipework may need reinforcement or a permanent mechanical repair.