I am using this same brand and model of tankless, i keep getting code 391 and wake to a cold floor/house. I had the gas company turn up the pressure to 8"wc and the problem went away for a few weeks however this code has returned. any suggestions? this is a new installation. I am using primary/secondary pumping with a TACO 0011 for the primary and TACO VT2218 on my radiant loops. it works pretty well but this tripping on 391 has me a bit pissed.
So you used one heater for both hot water to faucets and radiant heat? Thanks
I am using this same brand and model of tankless, i keep getting code 391 and wake to a cold floor/house. I had the gas company turn up the pressure to 8"wc and the problem went away for a few weeks however this code has returned. any suggestions? this is a new installation.
I am using primary/secondary pumping with a TACO 0011 for the primary and TACO VT2218 on my radiant loops. it works pretty well but this tripping on 391 has me a bit pissed.