Doing Off Peak? Or any kind of dual fuel? Then you'll want to add the Boiler Coordinator.  It automates switching between a main boiler and a backup boiler when the electric utility provides an “off-peak” signal. This little circuit board replaces several relay connections to coordinate the use of 2 boilers for any reason (it doesn't just have to be off peak).

The Off Peak Boiler Coordinator circuit board adds right on the HUG Hydronics In-floor Heating Control Board between pumps sections 8 & 9. Takes just minutes to install with standard tools, one more way HUG Hydronics is making in-floor heating simple.

Will be installed before shipping.

Boiler Coordinator Manual