Another new member caught in the authentication boondoggle.
New guy here trying to get some plumbing ordered before my boiler gets here. I'm currently running an oil boiler with baseboard heat. I will be installing my wood boiler to run through a 50 plate HX at the oil boiler and then probably a 20 plate for the DHW. The boiler will be approximately 120ft from the house. I plan on running 1-1/4in lines all the way to the house. Also the oil boilerd return line where the HX will be is 1-1/4in.
Should I stay with all 1-1/4in lines, valves, fittings ect. For everything inside?? It seems like this is the way to go, but at double the cost for fittings, etc. I just want to make sure it's the correct design. Or can I step down to 1in for what's inside? The oil boiler and DHW are within 10ft from the basement wall, so the inside run will be short.