Pennco Micro-Zoning / Flow Too Low Through Boiler

Boiler cycles on and off rapidly when only one small zone calls

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Possible Causes

Very small zone load, No boiler bypass, High boiler firing rate, Incorrect control settings

Safety first: Use caution around hot piping.

Observe operation: Note if short cycling only occurs on small zones.
Check bypass: Verify if a boiler bypass or primary/secondary piping is installed to maintain minimum flow through the Pennco boiler.
Adjust controls: If available, lower firing rate or adjust differential settings per manual.
System redesign: A heating professional may recommend combining small zones or adding a buffer tank.

Hard 4/5

Boiler Bypass Piping

Check Price on Amazon

We may earn a commission from links on this page.