Danfoss RTD-CB Back Flow Restrictor
Introduction
The Danfoss RTD-CB Back Flow Restrictor is an essential component designed for use in one-pipe heating systems, particularly when thermostatic radiator valves (TRVs) like the RTD-CB series are installed. Its purpose is to maintain correct flow direction and avoid unwanted backflow through the radiator, which helps ensure efficient heating and balanced system operation.
Overview
- Purpose: Prevents reverse flow through radiators in one-pipe systems.
- Application: Designed for use with RTD-CB valves in heating systems.
- Material: Typically made from durable brass or stainless steel for corrosion resistance.
- Compatibility: Specifically suited for Danfoss TRVs and compatible radiator setups.
- Installation Position: Installed on the return pipe directly after the radiator.
Specifications
- Model: 013R9467
- Product Name: RTD-CB Back Flow Restrictor
- Part Numbers: 013L1925 (DN 15), 013L1926 (DN 20)
- Model Type: DKCD
- Code: VICHA202
- Dimensions:
- DN 15: A=30mm, B=27mm
- DN 20: A=37mm, B=32mm
Installation Instructions
Tools Needed
- Adjustable wrench or spanner
- PTFE tape (if applicable)
- Pipe cutter (if adjustments are needed)
- Bucket or towel (to catch any water drips)
Step-by-Step Guide
- Turn Off the Heating System:
Make sure the central heating system is turned off and cooled down. - Drain the Radiator (if necessary):
Use the bleed valve or radiator drain to relieve any pressure and drain water from the radiator. - Locate the Return Pipe:
Identify the return side of the radiator – typically the cooler pipe when the system is running.
- Install the Restrictor:
- Remove the existing connector if needed.
- Insert the backflow restrictor into the valve or pipe fitting, ensuring the flow direction arrow on the restrictor matches the actual water flow.
- Use PTFE tape on threaded joints to prevent leaks.
- Tighten using a spanner or adjustable wrench.
- Check for Leaks:
Once installed, reopen the radiator valves and refill the system. Look for any leaks around the new restrictor. - Bleed the Radiator:
Bleed out any trapped air using the radiator bleed key. - Test the System:
Turn the heating system back on and ensure proper flow and function.
Tips
- Always consult the system layout or heating engineer if unsure of flow direction.
- If you’re working on a sealed system, remember to repressurize it after installation.
Product Usage Instructions
- Before installing, ensure the backflow restrictor is compatible with your system.
- Turn off the water supply to the system where the backflow restrictor will be installed.
- Identify the appropriate size based on your system requirements (DN 15 or DN 20).
- Place the backflow restrictor in line with the water flow direction indicated by the arrow on the device.
- Tighten the connections securely to prevent leaks.
- Turn on the water supply and check for any leaks. Adjust connections if necessary.
Frequently Asked Questions
- Q: Can the backflow restrictor be used for hot water systems?
A: The backflow restrictor is designed for cold water systems only. Do not use with hot water. - Q: How often should the backflow restrictor be checked for proper functioning?
A: It is recommended to check the backflow restrictor annually or whenever there is a noticeable decrease in water pressure. - Q: Can the backflow restrictor be installed vertically or horizontally?
A: The backflow restrictor can be installed in both vertical and horizontal positions as long as the flow direction is maintained.
Documents / Resources
 |
Danfoss RTD-CB Back Flow Restrictor [pdf] User Guide RTD-CB Back Flow Restrictor, RTD-CB, Back Flow Restrictor, Flow Restrictor, Restrictor |