2 zone hot water system. Zone 1 heats upstairs and uses the cast iron radiators. Zone 2 heats the basement and uses baseboard heating. I was putting in some new carpet and loosened solder on a joint on a radiator (only one downstairs) in a basement room. There is also a baseboard in this room and the thermostat for the zone 2. I drained and tried to repair 4 times, each time it leaks less (over night I accumulated 1/4 a teaspoon of water in the pan). I didn't notice but I have wire solder, so I'm going to try and get some plumbing solder before I try again. In putting the system on to test my first attempt to solder, I noticed this radiator was hooked up to the upstairs zone. I'm thinking I'm better off pulling the old radiator and cap the lines. I can get to the main pipe and cap where the two line come off it right next to each other. My wife was concerned that with just the baseboard it might be colder in that room, but I think having that extra radiator working off zone 1 messes up the thermostat in the room for zone 2 making the whole basement less efficient. Just double checking I'm making the right choice and that I can just cap those two lines. I would be capping off the main line which looks to be 2" maybe. I got 1/2" on the hot water, the main for the house is bigger looks 3/4" maybe 1", the heating line is bigger than that, at least 1 1/2". There is are couplings with a 1/2" lines coming off for each radiator. At this coupling is where I was going to cap it.