Should I remove a radiator

[schmidty169]

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.

[jadnashua]

There's a good reason just trying to add solder to an old, wetted joint doesn't work - contamination. The only way to make a good solder joint is to start with clean, properly fluxed pipe and fittings. So, if you didn't take that fitting off, clean everything up, flux then try to solder it, that is why it did not stop leaking.

Having a radiator from a different zone would certainly affect the thermostat and ultimate comfort of that zone. Whether you'd get enough heat in there with what you have if you eliminated that one is hard to tell without knowing the actual heat load. As to whether that's a viable way to remove it, also can't say without seeing it (at least I can't, maybe a pro is following your better than I).

[Dana]

The basement radiator on the zone 1 upstairs zone isn't "messing up" the thermostat for the zone-2 basement baseboards any more than turning on all the lights and watching TV on the big screen in the basement does. Nor does it affect the overall efficiency of the basement zone. It may be heating the basement sometimes when the heat load in the basement is low, but it's still all inside the thermal envelope of the house.

It's mostly a room-to-room zone balance issue. The heat loss characteristics of basements are quite a bit different from the rest of the house, and if you try to run it all as one zone, if you sized the radiator to meet the heat load when the upper floors have only extremely light loads it might roast you out of the basement when the upper floors have a serious heat load going, so it was probably intentionally undersized for average basement load to avoid over heating the basement, which is why adding the baseboards with a separate thermostat was necessary to keep it comfortable down there.

Whether that radiator is currently necessary or not depends on the actual heat loads in the basement and how much baseboard you have on that zone & room. If you just pull the radiator it might be necessary for you to better insulate the foundation walls of that room or add some baseboard for it to continue to maintain temperature balance with the rest of the zone (provided it ever really DID balance, which may be in question.)

If you clean it up and use the right solders & fluxes you should be able to repair the solder on that connection almost as easily as capping off the branches at the mono-flow tees.

[schmidty169]

I was thinking if the bedroom door was closed and the upstairs heat was on then this room would be hotter then the rest of the basement. The thermostat would read 75 and not turn on the heat downstairs which is set to 68. The rest of the basement could be 50 but because the thermostat doesn't drop below 68 the heat doesn't come on. Now these are just numbers thrown out there, but I have experienced it nice a toasty in this room while the rest of the basement was cold if the door gets closed. Now if the door is left open it balances. But being a room my daughter like to have privacy and kept the door closed (can't say I blame her), but my office is damn cold like this. Now each of the five rooms downstairs has its own baseboard. Even if I repair it (which is still a distinct possibility as its not anymore work to fix it then try to cap off). I might have to try and adjust that radiator to put out less heat so as not to over heat the room and cause the thermostat to not turn on the heat. I also considered regulators through the closet to the rest of the basement to create flow and try to balance the heat. You can see my calumdrum.

[jadnashua]

There are thermostatic radiator valves that let you have individual control over each item - it's a replacement for the shutoff valve. The potentially better solution would be to have that radiator connected to the same zone as the rest of the basement rather than upstairs, but that's more work.

[Dana]

Microzoning has it's own issues, but if you're looking for an overheated hot micro-zone controlled by a thermostat on a different floor your results will vary by more than just the outdoor temperature.

If the basement walls are not insulated and air sealed you'll see very significant room to room temperature differences since the heat losses can be quite high for the R1 above-grade portion of the walls. No matter what your heating fuel is, if you're conditioning the basement it's worth putting an inch of rigid foam on the walls trapped to the foundation by a studwall with unfaced batts (or 2-3" of foam held in place with furring through screwed to the foundation with TapCons on which to hang the gypsum), including the foundation sill & band joists, all sealed up with 1-part can foam or FrothPak. The payback on comfort is immediate, and if you're heating with oil it could pay back in single-digits of years if you use reclaimed roofing insulation rather than virgin-stock foam. (Search the craigslist materials sections- there are several players in the reclaimed foam biz advertizing in southern New England).