Red screen was maintenance reminder. I reset it I lowered storage tank from 130 to 120. Turned on all thermostats. Checked master bedroom hallway radiator for noise. Just heard regular clicking noise as the metal expands on the radiator. Couldn’t find anything that was unusual with it. Ultimate Heating Tune-Up Gas Heat: serviced and inspected gas heating system checking water flow ,water temperature rise, electrical, gas pressure, safeties, controls and limits, heat exchanger and venting. cleaned and checked system components to manufacturer specifications and performed combustion inspection