15mm WRAS Approved Filling Loop
Fill and Top Up Sealed Heating Systems
Sealed heating systems need the correct water pressure to operate properly.
A filling loop provides a temporary connection between the cold mains supply and the heating circuit.
Therefore, installers and homeowners can restore system pressure when required.
Always follow the boiler or heating-system manufacturer’s filling instructions.
15mm Compression Connections
This filling loop uses 15mm compression connections.
Therefore, it suits compatible 15mm copper pipework.
Compression fittings also make installation straightforward. In addition, they allow easy replacement during future maintenance.
Always check the existing pipe size before ordering.
WRAS Approved Filling Loop
This filling loop carries WRAS approval.
WRAS-approved filling-loop assemblies use backflow protection to help protect the mains water supply. The design commonly combines isolation valves, a flexible hose and a double check valve. (wrasapprovals.co.uk)
Therefore, this product suits professional plumbing and heating installations where an approved filling loop is required.
Double Check Valve Protection
The filling loop includes a double check valve.
This helps prevent heating-system water from flowing back toward the mains supply.
Therefore, the valve provides an important layer of backflow protection.
The flow direction should always follow the markings on the valve body.
Isolation Valves Included
Isolation valves allow the installer to control water flow through the filling loop.
Open the valves only when filling or topping up the system.
Once the correct pressure is reached, close both valves.
The flexible connection should then remain isolated in line with the system requirements.
Flexible Braided Hose
The filling loop includes a flexible braided hose.
This makes it easier to connect the mains supply to the sealed heating circuit.
The flexible design also helps where the two connection points do not align perfectly.
However, avoid twisting or sharply bending the hose during installation.
Ideal for Boilers and Heating Systems
The 15mm filling loop can suit compatible:
- Sealed central heating systems
- Combination boiler installations
- System boilers
- Heating system replacements
- Boiler servicing
- Heating system commissioning
- Radiator heating systems
- Compatible underfloor heating systems
Always check the appliance manufacturer’s installation requirements.
Restoring Heating System Pressure
Heating-system pressure can fall over time.
For example, pressure may drop after radiator bleeding or maintenance.
A filling loop allows water to enter the system again.
However, regularly falling pressure can indicate another problem.
Therefore, investigate repeated pressure loss rather than continually topping up the system.
How to Use a Filling Loop
First, check the required system pressure.
Next, slowly open the filling-loop valves.
Watch the boiler or system pressure gauge while water enters the circuit.
Then close the valves once the correct pressure is reached.
Finally, check the system for leaks.
Never over-pressurise the heating system.
Replacement Filling Loop
Filling loops may eventually need replacement.
Common reasons include:
- Leaking flexible hose
- Seized isolation valves
- Damaged compression fittings
- Failed check valve
- Corrosion
- Boiler replacement
- Heating-system upgrades
- General servicing
This 15mm version provides a simple replacement where the existing system uses compatible connections.
Technical Specifications
| Specification | Details |
|---|---|
| Brand | Kudos Trading |
| Product | WRAS Approved Filling Loop |
| SKU / EAN | 5060950076161 |
| Connection Size | 15mm |
| Connection Type | Compression |
| Hose | Flexible braided hose |
| Isolation Valves | Included |
| Double Check Valve | Included |
| WRAS Approved | Yes |
| Application | Filling sealed heating systems |
| Pipe Compatibility | Compatible 15mm copper pipework |
Why Choose a 15mm Filling Loop?
A dedicated filling loop provides a simple way to maintain system pressure.
Key benefits include:
- WRAS approved
- 15mm compression connections
- Double check valve included
- Isolation valves included
- Flexible braided hose
- Easy system filling
- Simple pressure top-up
- Suitable for sealed heating systems
- Ideal for replacement work
- Compact installation
Filling Loop vs Filling Valve
The terms often describe closely related components.
A filling loop usually refers to the complete flexible hose and valve assembly.
Meanwhile, a fill valve controls the water entering the system.
This product combines the required filling-loop components into one assembly.
Why Buy From Kudos Trading?
Kudos Trading supplies professional plumbing, heating and underfloor heating products throughout the UK.
We stock filling loops alongside isolation valves, check valves and other heating-system components.
Therefore, installers can order several related plumbing products from one supplier.
In addition, we have supplied underfloor heating products to the UK for over 26 years.
Frequently Asked Questions
What Does a Filling Loop Do?
A filling loop allows mains water to enter a sealed heating system.
Therefore, it lets you fill or restore system pressure when required.
What Size Connections Does This Filling Loop Have?
This model uses 15mm compression connections.
Always check the existing pipework before ordering.
Is This Filling Loop WRAS Approved?
Yes.
This product is listed as a WRAS approved 15mm filling loop. (kudostrading.co.uk)
Does It Include a Double Check Valve?
Yes.
The filling loop includes a double check valve to help prevent backflow.
Does It Include Isolation Valves?
Yes.
Isolation valves allow you to control the water entering the heating circuit.
Can I Use It on a Combi Boiler?
It can suit compatible combi boiler installations that require an external filling loop.
Always check the boiler manufacturer’s instructions first.
Can I Use It on a System Boiler?
Yes, where the sealed heating system uses a compatible external filling arrangement.
Always check the system design before installation.
Can I Leave the Filling Loop Open?
No.
Close the filling valves once the correct heating-system pressure is reached.
Leaving them open could over-pressurise the system.
Why Does My Boiler Pressure Keep Dropping?
Occasional pressure loss can follow maintenance or radiator bleeding.
However, repeated pressure loss may indicate a leak, expansion-vessel issue or another system fault.
Therefore, investigate the cause if regular topping up becomes necessary.
Can I Use This as a Replacement Filling Loop?
Yes, provided the connection size and system requirements match.
Always compare the existing filling loop before ordering.
Related Products
- 15mm Double Check Valve
- 15mm Single Check Valve
- 15mm Isolating Valve
- 15mm Lever Ball Valve C*C Full Bore WRAS Approved
- 15mm Shock Arrestor Compression Fitting
- Check Valves
- Isolation Valves
- Pipe, Valves & Fittings
Next Working Day Delivery
We hold our products in stock at our 7,000 sq ft Nottingham warehouse.
Order before 12pm for dispatch using our tracked next-working-day DPD service.
Delivery options and charges depend on your postcode.
Collection Available
You can always collect from our Nottingham location and help yourself to a free tea or coffee.
