I'm seeking assistance regarding connecting a C-wire (for Ecobee) to a new boiler using the Fast-Stat common maker. The new boiler currently has two thermostat wires available for connection. However, my thermostat wire has only two wires, and replacing it is difficult due to its location on the second floor. I'm wondering if it's feasible to utilize the Fast-Stat common maker in this situation. It is one zone system with one circulator. Any guidance or advice would be highly appreciated. The control board is 109632-01 and the boiler is RRG 84% AFUE Natural Gas Water Boiler with 100,000 BTU Input and 73,000 Output. Thank you so much for your help!
My thoughts are to: 1. splice PI (pink) and connect it to the red thermostat wire to make it R. Then 2. splice BR (brown) and connect it to black (C) common maker. I attached the picture from what I think is the closest from the diagrams.