Fernox F4 Leak Sealer Liquid
Reduce pressure loss from sealed systems by sealing small leaks.
| Product Code | Size | Quantity | |
|---|---|---|---|
| 391806 | 500ml | 10/td> | Login |
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- PEGASUS PressFit Fittings & Valves
- PressFit Butterfly Ball Valves
- PressFit Isolating Valves
- PressFit Lever Ball Valves
- PressFit Fittings (Water)
- Fittings Bucket 100
- Coupler C x C
- Slip Coupler C x C
- Fittings Bucket 110
- Fitting Reducer C x C
- Reducing Coupler C x C
- Coupler C x MI
- Coupler C x FI
- Elbow C x C
- Street Elbow C x C
- Obtuse Elbow C x C
- Obtuse Street Elbow C x C
- Elbow C x MI
- Elbow C x FI
- Wallplate Elbow C x FI
- Stopend C
- Tee C x C x C
- Reducing Tee C x C x C
- Reducing Tee – Female C x C x FI
- Crossover (Part) C
- Crossover (Full) C x C
- PressFit Fittings (Gas)
- PEERLESS Wastes
- Basin Wastes
- Basin Wastes – Brushed Nickel
- Basin Wastes – Black (Matt)
- Basin Wastes – Gold
- Basin Wastes 'Easy Clean' – Chrome
- Basin Wastes – Chrome
- Plastic Body – Back Nut Fixing
- Plastic Body – Centre Screw Fixing
- Brass Body – Plastic Back Nut
- Brass Body – Metal Back Nut
- Brass Body – Brass Back Nut
- Clicker Plug – Brass Body
- Central Clicker Plug – Brass Body
- Flat Mushroom Clicker – Brass Body
- Square Clicker – Brass Body
- Captive Plug – Brass Body
- Flip Plug – Brass Body
- Free Flow – Brass Body
- Shrouds
- Pop-Up Assembly – Brass Body
- Vanity Basin Combination
- Vanity Basin Combination Enflow Pattern
- Bath Wastes – Black (Matt)
- Bath Wastes – Gold
- Bath Waste 'Easy Clean' – Chrome
- Bath Wastes – Chrome
- 'Tubby' Waste – Brass Body – Plastic Back Nut
- 'Tubby' Waste – Brass Body – Metal Back Nut
- 'Tubby' Waste – Brass Body – Brass Back Nut
- Clicker Plug – Brass Body – Plastic Back Nut
- Flat Mushroom Clicker – Brass Body – Plastic Back Nut
- Square Mushroom Clicker – Brass Body – Plastic Back Nut
- Flip Plug – Brass Body – Plastic Back Nut
- Pop-Up Waste and Overflow – Clicker
- Pop-Up Waste and Overflow – Mushroom
- Deluxe Pop-Up Waste and Overflow – Clicker
- Combination Overflow – Centre Screw – Plastic Body
- Combination Tidy Plug – Brass Face
- Combination Enflow Pattern – Brass Body – Plastic Back Nut
- Combination Enflow Pattern – Brass Body – Metal Back Nut
- Combination Enflow Pattern – Brass Body – Brass Back Nut
- Combination Clicker Plug – Brass Overflow Face
- Combination Mushroom Clicker – Brass Overflow Face
- Combination Contemporary Mushroom Clicker – Brass Overflow Face
- Combination Contemporary Clicker – Brass Overflow Face
- Combination Square Clicker Plug
- Combination Flip Plug – Brass Overflow Face
- Exposed Bath Waste
- Sink Wastes – Chrome
- 'Belfast' Waste – Brass Body – Plastic Back Nut
- 'London' Waste – Brass Body – Plastic Back Nut
- 'Belfast' Waste – Brass Body – Metal Back Nut
- 'London' Waste – Brass Body – Metal Back Nut
- 'Belfast' Waste – Brass Body – Brass Back Nut
- 'Tubby' – Brass Body – Poly Plug
- Combination Overflow – Plastic Body – Centre Screw
- Combination Overflow – Plastic Body
- Stainless Steel Basket Strainer
- Flush Grated Wastes – Chrome
- Flush Grated with Removable Top 3.3/8” – Brass Body – Plastic Back Nut
- Flush Grated 2.7/16” – Brass Body – Plastic Back Nut
- Flush Grated 2.7/16” – Brass Body – Metal Back Nut
- Flush Grated 2.7/8” – Brass Body – Plastic Back Nut
- Flush Grated 2.7/8” – Brass Body – Metal Back Nut
- Flush Grated 3.3/8” – Brass Body – Plastic Back Nut
- Flush Grated 3.3/8” – Brass Body – Metal Back Nut
- Flush Grated with Removable Top 2.7/8” – Brass Body – Plastic Back Nut
- Sink Wastes – White
- Combined Shower Wastes
- Urinal Wastes
- Caravan Wastes
- Bath Fillers
- Bottle Traps
- Chains
- Plug & Chains
- Plugs
- Chain Stays
- Stoppers
- Back Nuts
- Peerless Waste Spares
- Toilet Fittings
- General Valves
- Bib Taps
- Stopcocks
- Gate Valves
- MT Draw-Off Cocks
- Pump Valves
- Isolating Valves
- Check Valves
- Washing Machine Valves & Accessories
- Ball Valves
- Float Valves
- High Pressure Pt 1 – Side Inlet
- High Pressure Part 1 – 1/2" (8.3/4" arm, nylon seat)
- High Pressure Part 1 – 1/2" All Brass (8.3/4" arm)
- High Pressure Part 1 – 1/2" (10" arm, nylon seat)
- High Pressure Part 1 – 3/4" (13" arm, nylon seat)
- High Pressure Part 1 – 1" (16" arm, brass seat)
- High Pressure Part 1 – 1.1/4" (16" arm, brass seat)
- High Pressure Part 1 – 1.1/2" (18" arm, brass seat)
- High Pressure Part 1 – 2" (22" arm, brass seat)
- High Pressure Pt 1 – Bottom Inlet
- High Pressure Pt 2 – Side Inlet
- High Pressure Pt 2 – Bottom Inlet
- Low Pressure Pt 1 – Side Inlet
- Low Pressure Pt 1 – Bottom Inlet
- Low Pressure Pt 2 – Side Inlet
- Low Pressure Pt 2 – Bottom Inlet
- High Pressure Pt 1 – Side Inlet
- Floats
- Accessories
- Flexible Tap Connectors
- Compression Fittings
- COMPACT Compression Fittings
- Compression Bucket
- Coupler C x C
- Slip Coupler C x C
- Repair Coupler C x C
- Reducing Coupler C x C
- Reducer (1 Part)
- Reducer (3 Part)
- Coupler C x MI (No Flange)
- Coupler C x MI
- Coupler C x FI
- Flange Tank Connector
- Elbow C x C
- Elbow C x MI
- Elbow C x FI
- Wallplate Elbow C x FI
- Tee C x C x C
- Unequal Tee C x C x C
- Blanking Disc
- Olives
- Stopend C
- Nut
- Heavy Pattern Compression Fittings
- Coupler C x C
- Spigot Coupler
- Repair Coupler C x C
- Reducing Coupler C x C
- Coupler C x MI
- Coupler C x MI (Taper Thread)
- Coupler C x FI
- Tap Connector
- Flange Tank Connector
- Elbow C x C
- Elbow C x MI
- Elbow C x FI
- Wallplate Elbow C x FI
- Tee C x C x C
- Unequal Tee C x C x C
- Unequal Tee Female C x C x FI
- Unequal Tee Female C x FI x C
- Olives
- Stopend C
- Nut
- DZR Compresssion Fittings
- Chrome Compression Fittings
- Compression Adaptors and Couplers
- Copper Tube
- COMPACT Compression Fittings
- End Feed Fittings
- ECOPLUS (WRAS)
- ATOMIC (WRAS)
- End Feed Buckets
- Coupler C x C
- Slip Coupler C x C
- Imperial / Metric Coupler C x C
- Coupler MI x C
- Coupler C x FI
- Reducing Coupler C x C
- Fitting Reducer C x C
- Long Tail Fitting Reducer C x C
- Elbow C x C
- Elbow MI x C
- Elbow FI x C
- Long Radius Elbow C x C
- Long Radius Street Elbow C x C
- 45° Obtuse Elbow C x C
- 90° Street Elbow C x C
- 90° Street Elbow (Long Tail) C x C
- 45° Obtuse Street Elbow C x C
- Wall Plate Elbow C x FI
- Wall Plate Adaptor C x FI
- Cylinder Union FI
- Tap Connector C x Nut
- Equal Tee C x C x C
- Unequal Tee C x C x C
- Unequal Tee Female
- Stopend C
- Crossover C x C
- Manifold
- FUSION (Kitemark)
- End Feed Bucket
- Coupler C x C
- Slip Coupler C x C
- Metric / Imperial Coupler C x C imp
- Coupler MI x C
- Coupler C x FI
- Reducing Coupler C x C
- Fitting Reducer C x C
- Fitting Reducer (Long Tail) C x C
- Elbow C x C
- Elbow MI x C
- Elbow FI x C
- 90° Street Elbow C x C
- 90° Street Elbow (Long Tail) C x C
- 90° Long Radius Bend C x C
- 45° Obtuse Elbow C x C
- 45° Obtuse Street Elbow C x C
- Wallplate Elbow/Adaptors C x FI
- Cylinder Union FI
- Tap Connector C x Nut
- Equal Tee C x C x C
- Unequal Tee C x C x C
- Unequal Tee Female
- Stopend C
- Crossover C x C
- Manifold
- Brass and Black Iron Fittings
- Gas Fittings
- Tesla Gas Hoses
- Gas Hose Connectors
- Gas Cocks
- Mini Lever Ball Valves
- Restrictor Elbows & Tubes
- Tesla Test Point Fittings
- Meter Unions & Accessories
- Accessories
- Arctic Hayes Gas Products
- Flexigas
- Tools, Pipe Clips & Ventilation
- ARCTIC Hayes
- Ecopclip Modular Fixing System
- REMS
- Monument Tools
- Tools
- Kibosh
- Copper and Brass Pipe Clips
- Rubber Lined Clips & Accessories
- Hose Clips
- Embrass Peerless Pipe Clips
- Talon Clips, Trunking & Covers
- Airflow Ventilation
- Miscellaneous
- Drainage Products
- Plumbing Compounds
- Everbuild
- Sealants
- Embrass Peerless Chemicals
- Calmag
- Fernox
- Scalemaster
- La-Co
- Wiseman
- Evo-Stik
- BOSS
- Templers Flux
- FloPlast
- PTFE
- Vitcas
- Solder
- Metallic Wool
- Arctic Hayes
- Silicone Sealant
- Tapes
- MIscellaneous
- Electrical Fittings and Cable
- Water Storage
- Embrass Peerless Flush and Fill
- Fluidmaster Flush and Fill
- Torbeck Flush and Fill
- Delchem Flush and Fill
- Dudley Siphons
- Float Valve Spares
- Siphon Spares
- Concealed Cisterns
- Pan Connectors
- Embrass Peerless Toilet Seats
- Toilet Fittings & Pipe
- Toilet and Cistern Accessories
- Water Meters
- Washers & Repair Boxes
- Lagging and Insulation
- Polytank
- Plastic Tanks
- Taps and Shower Products
- Euroshowers
- ShowerSeal
- Shower/Bath Seals 1m
- 4-6mm Glass 7mm Drop (SEAL001)
- 4-6mm Glass 7mm Drop (SEAL011)
- 4-6mm Glass 12mm Drop (SEAL002)
- 4-6mm Glass 12mm Drop (SEAL003)
- 4-6mm Glass 12mm Drop (SEAL004)
- 4-6mm Glass 16mm Drop (SEAL005)
- 4-6mm Glass 16mm Drop (SEAL006)
- 4-6mm Glass 23mm Drop (SEAL007)
- 4-6mm Glass 25mm Drop (SEAL008)
- 8-10mm Glass 7mm Drop (SEAL009)
- 8-10mm Glass 12mm Drop (SEAL010)
- 8-10mm Glass 35mm Drop (SEAL044)
- Shower/Bath Seals 2m
- Magnetic Door Seals 2m
- Bi-Fold/Channel Seals 2m
- Shower/Bath Seals 1m
- Shower Valve and Fixing Brackets
- Tap Fittings
- Plastic Fittings
- Embrass Peerless Traps
- Plastic Traps
- Solvent Weld
- Pushfit
- Mechanical Waste Connectors
- MDPE Pipe
- FloPlast
- Soil – 110mm Ring Seal PVC-U
- Grey
- Pipe – Plain Ended
- Pipe – Single Socket
- Universal Pipe Connector
- Drain Connector
- Pipe Clip
- Socket Clip
- Single Socket Coupling
- Double Socket Coupling
- 0-90° Adjustable Bend
- 92.5° Single Socket Bend
- 92.5° Double Socket Bend
- 112.5° Single Socket Bend
- 135° Single Socket Bend
- 135° Double Socket Bend
- 92.5° Branch
- 112.5° Branch
- 135° Branch
- 92.5° Double Branch
- 92.5° Access Bend
- 92.5° Corner Branch
- 92.5° Access Branch
- Access Pipe – Socket/Spigot
- Access Pipe – Socket/Solvent Weld
- Screwed Access Plug
- Socket Plug
- Strap Boss
- Soil Manifold
- Boss Pipe – Socket/Spigot
- Boss Pipe – Socket/Solvent Weld
- Boss Pipe – Short
- Offset Bend – Top
- Offset Bend – Bottom
- Round Shoe
- Weathering Collar
- Vent Terminal
- Extract Cowl
- Reducer
- Solvent Boss Adaptor
- Rubber Boss Adaptor – Push Fit
- Weathering Slate
- Black
- Pipe – Plain Ended
- Pipe – Single Socket
- Universal Pipe Connector
- Drain Connector
- Pipe Clip
- Socket Clip
- Single Socket Coupling
- Double Socket Coupling
- 0-90° Adjustable Bend
- 92.5° Single Socket Bend
- 92.5° Double Socket Bend
- 112.5° Single Socket Bend
- 135° Single Socket Bend
- 135° Double Socket Bend
- 92.5° Branch
- 112.5° Branch
- 135° Branch
- 92.5° Double Branch
- 92.5° Access Bend
- 92.5° Corner Branch
- 92.5° Access Branch
- Access Pipe – Socket/Spigot
- Access Pipe – Socket/Solvent Weld
- Screwed Access Plug
- Socket Plug
- Strap Boss
- Soil Manifold
- Boss Pipe – Socket/Spigot
- Boss Pipe – Socket/Solvent Weld
- Boss Pipe – Short
- Offset Bend – Top
- Offset Bend – Bottom
- Round Shoe
- Weathering Collar
- Vent Terminal
- Extract Cowl
- Reducer
- Solvent Boss Adaptor
- White
- Pipe Single Socket
- Pipe Clip
- Single Socket Coupling
- Double Socket Coupling
- 0-90° Adjustable Bend
- 92.5° Single Socket Bend
- 112.5° Single Socket Bend
- 135° Single Socket Bend
- 92.5° Double Socket Bend
- 135° Double Socket Bend
- 92.5° Branch
- 112.5° Branch
- 135° Branch
- 92.5° Access Bend
- 92.5° Access Branch
- Access Pipe – Socket/Spigot
- Screwed Access Plug
- Socket Plug
- Strap Boss
- Boss Pipe – Socket/Spigot
- Boss Pipe – Short
- Offset Bend – Top
- Offset Bend – Bottom
- Weathering Collar
- Vent Terminal
- Extract Cowl
- Solvent Boss Adaptor
- Grey
- Soil – 110mm Solvent PVC-U
- Black
- Pipe – Plain Ended
- Clip
- Double Socket Coupling
- Single Socket Coupling
- 90° Single Socket Bend
- 92.5° Double Socket Bend
- 135° Double Socket Bend
- Offset Bend – Top
- Offset Bend – Bottom
- 92.5° Branch
- 135° Branch
- 92.5° Access Bend – Double Socket
- 92.5° Access Branch – Triple Socket
- Access Pipe – Double Socket
- Screwed Access Plug
- Boss Pipe – Short
- Strap Boss
- Vent Treminal
- Solvent Boss Adaptor
- Black
- Air Admittance Valves
- ABS Solvent Weld Waste System
- Pushfit Waste System
- Overflow Waste System
- 112mm Half Round Guttering and Fittings
- 68mm Round Downpipe and Fittings
- 110mm Underground Drainage PVC-U
- Equal Junction
- Pipe
- Socket Coupling
- Single Socket Bend
- Double Socket Bend
- Long Radius Bend
- Non Return Valve
- Access Fittings
- Rodding Point
- Drainguard
- Universal Gully Trap
- P Trap
- Interceptor Gully
- Square Hopper
- Rectangular Hopper
- Bottle Gully Trap
- Waste Reducer
- Reducer
- Clay Adaptor
- Flexible Rubber Fitting
- Socket Plug
- Large Inspection Chamber
- Mini Access Chamber
- 160mm Underground Drainage PVC-U
- 110mm Domestic Channel Drainage
- FloFit +
- MDPE Fittings
- Soil – 110mm Ring Seal PVC-U
- Philmac Plastic Compression
- Metric Imperial Fittings
- Coupler
- Slip Coupler
- Reducing Coupler
- End Connector Male
- End Connector Female
- Equal Tee
- Unequal Tee
- Female Tee
- Elbow
- Reducing Elbow
- Male Elbow
- Female Elbow
- End Cap
- Coupler Copper/Push Fit
- Wall Plate Elbow Plastic
- Wall Plate Elbow Metal
- Reducing Sets
- Tank Connector Assembly
- MDPE Liner
- Pipe Repair Kit
- Metric Imperial Accessories
- Metric Imperial Valves
- Universal Transition Couplings
- Metric Imperial Fittings
- Wavin
- Hep2O Pipe
- Hep2O Fittings
- Hep2O Valves
- Hep2O Flexibles Std Bore
- Hep2O Flexibles Full Bore
- Hep2O Manifolds
- Hep2O Accessories
- Hep2O Adaptors
- HepVO Problem Solvers
- OSMA Problem Solvers
- Speedfit Plumbing
- SpeedFit Underfloor Heating
- Barrier Pipe
- Plumbing Fittings
- Stem Adaptor – Female
- Stem Adaptor – Male
- Reducer
- Male Coupler – Brass
- Female Coupler
- Reducing Elbow
- Wall Plate Elbow – Brass
- Stem Elbow
- 135° Stem Elbow
- Imperial / Metric Conversion Coupler
- Tee
- Tank Connector
- Stopend
- Plug
- Pipe Repair Kit
- Coupler
- Elbow
- Reducing Tee
- Reducing Coupler
- Tap Connector (Plastic)
- Plumbing Valves
- Flexibles
- Sundries
- RWC Valves
- MDPE (Blue)
- PolyPlumb
- Barrier Pipe
- Plumbing Fittings
- Polyplumb Enhanced
- Enhanced Bent Tap Connectors (Brass Nut)
- Enhanced Blank End Sockets
- Enhanced Couplers
- Enhanced Double Manifolds
- Enhanced Elbows
- Enhanced Equal Tees
- Enhanced Reducing Couplers
- Enhanced Reducing Tee
- Enhanced Reducing Tees
- Enhanced Socket Reducers
- Enhanced Spigot Elbows
- Enhanced Straight Tap Connectors (Brass Nut)
- Enhanced Tank Connectors
- Enhanced Tap Connectors (Plastic)
- Enhanced Wallplate Elbows
- Coupler
- Elbow
- Reducing Tee
- Reducing Coupler
- Tap Connector (Plastic)
- Spigot Elbow
- Wall Plate Elbow
- Equal Tee
- Spigot Reducer
- Socket Reducer
- Tank Connector (cold water only)
- Tap Connector (Brass)
- Flexibles
- Male Adaptor DZR
- Female Adaptor DZR
- MDPE Polyfast Adaptor
- Manifold Single Sided
- Manifold Double Sided
- Spigot Blank Ends
- Socket Blank Ends
- Socket Blank Ends (Demountable)
- Polyplumb Enhanced
- Plumbing Valves
- Plumbing Sundries
- Heating Products
- ESI Heating Controls & Accessories
- Eden Thermostatic Radiator Valves
- Manual Radiator Valves
- Towel Rail Radiator Valves
- Towel Rail Thermostatic Valves
- Towel Rails
- Towel Rail Heating
- Embrass Peerless Heating Products
- Emmeti Heating Valves and Controls
- RWC Heating Valves and Controls
- Heating Valves and Controls
- EA5YPlug Wiring Centre 3-5 Way
- Tesla Cylinder Accessories
- Tesla Flexible Hose Tap Adaptors
- Tesla Heat Pump Accessories
- Tesla Heat Pump Acessories
- Tesla Wiring Centres
- Tesla Y-Strainer
- Pressure Reducing Valve c/w Gauge
- Angled By-Pass Valve
- Auto Bottle Air Vents
- Auto Bottle Air Vents – Slimline
- Water Hammer Arresters
- Dual Cylinder Thermostat
- Tesla Teslatun Dry Trap Tundish
- Tesla Straight Tundish
- Heating Miscellaneous
- RWC Expansion Vessels
- Immersion Heaters & Accessories
- Expansion Vessel Accessories
- Cylinder Flanges
- Terminal Guards
- Fire Valves
- Oil Fittings
- Radiator Accessories
- Polypipe Underfloor Heating
- Novatherm Underfloor Heating
- Multilayer Pipe
- Manifolds & Accessories
- UFH Kits
- Electric UFH Mat
- Controls, Pumps & Actuators
- Accessories
- Novatherm Thermostats
- Controls/Accessories
- Heatmiser Thermostats
- Levelling, Adhesives & Primers
- Boards
- Floor Panels
- Fibre Boards
- Miscellaneous Boards
- P1 Pre-Pack Plumbing
- General Valves & Fittings
- Appliance Hoses & Accessories
- Flexibles
- Brass Fittings
- Compression Fittings
- Compression Fittings CP
- End Feed Fittings
- Heating Products
- Solder Ring Fittings
- Gas Products
- Pipe Clips
- Plumbing Accessories
- Mechanical Waste
- Speedfit Fittings
- Wastes & Accessories
- Toilet Fittings
- Float Valve – Brass
- Repair Kit
- Plastic Float Valve
- Overflow Stopper
- Overflow Pipe
- Flush Cone Fitting
- Flush Pipe Connector
- Plastic Piston
- Plastic Seat
- Cotter Pin
- Siphon Nut
- Siphon Bolt Kit
- Toilet Pan Screw Set
- Sanitary Fixing Kit
- Cistern Levers
- Cistern Lever Kits
- Cistern Lift Arms
- Cistern C Links
- Seat Hinges – Plastic
- Close Couple Cistern Kit
- Washers
- Plastic Washer
- Pillar Tap Washer
- Universal Top Hat Washer
- Siphon Washer
- Conical Trap Washer
- Rubber Waste Washer
- Washing Machine Hose Washer
- Flat Tap Washer
- Vacca Tap Washer
- Delta Tap Washer
- Pegler Tap Washer
- Dome Tap Washer
- Shower Hose Washer
- Pump Gasket
- MT Cock Washer
- Donut Washer
- Flat Trap Washer
- O-Ring Pack
- Flexible Tap Washer
- Fibre Washer
- Float Valve Washers & Seat
- Stands
- Solder Ring Fittings
- Solder Ring Bucket
- Coupler C x C
- Slip Coupler C x C
- Metric / Imperial Coupler C x C imp
- Coupler C x MI
- Coupler C x FI
- Reducing Coupler C x C
- Fitting Reducer C x C
- Elbow C x C
- Elbow C x MI
- Elbow C x FI
- 90° Street Elbow C x C
- 45° Obtuse Elbow C x C
- Wallplate Elbow FI x C
- Cylinder Union – Straight C x Nut
- Tap Connector C x Nut
- Equal Tee C x C x C
- Unequal Tee C x C x C
- Crossover C x C
- Stopend C
