temporary buffer tank and nti 300

duffy_4

just finished part of a job on a 9 flat apt building,owners 100 gal comm dhw tank leaking and he had a 50 yr old WMC cast iron 500,000 but C.I. heater,he decided upgrade to to high eff equipment so i hung nti 300 boiler and prepiped as much as i could,venting ,elect,gas..etc ,then swapped out leaking tank for 120 gal indirect worked fine,planned on pulling ci boiler in spring and install 80 gal buffer tank and repipe distribution system[6 high temp zones ,3 in floor low temp copper tubing]in spring as its middle of winter and couldnt go without heat for 2 days it woulda took me.came up with idea of using existing boiler as temp buffer tank as it had a 3 inch plug port on top of it and leaving distribution piping alone,figured i could accomplish that in one day,if it didnt work i could just close valves and turn gas back on to existing boiler and reinstall flu.after few hiccups with lwco switch on new boiler its working beautiful about 20 min on time followed by roughly 40 min off depending on amount of zones calling working off outdoor reset

duffy_4

buffer tank

overview