Primary Circuit Flow Rate Out of Range – Exceeds max or falls below min

What does Primary Circuit Flow Rate Issue mean?

The boiler's primary circuit requires the system flow rate to be within specified maximum and minimum limits for efficient and reliable operation. Flow rates outside this range, or unknown flow rates, can cause system inefficiencies.

• Improper system design or pipe sizing
• Incorrect pump selection or settings
• Lack of a low-loss header in systems where flow rates are challenging to manage
• Increased system load

Click steps to track your progress.

1. 1

   Consult page 9 of the manual for the boiler's maximum flow rate limitations for your specific model.

2. 2

   If the system flow rate is unknown or suspected to be out of range, Viessmann strongly recommends installing a low-loss header.

3. 3

   Have a qualified heating technician evaluate the system's hydraulic design and pump performance.

4. 4

   Ensure all pumps are correctly sized and configured for the specific application.