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A Shoulder Season Problem
Long timer lurker, very infrequent participant.
I've been in my current house for a bit over three years, now. Little background my house is heated by 1 pipe steam, which generally runs very well, with one exception, the finished attic space in the shoulder season.
This room is generally between 3 and 6 degrees colder than either the first or second floors during mild weather, basically any out door temperature in the 30's or above. Once we get below that it's fine.
An un-related issue with an animal getting into the knee walls has given me the "opportunity" to open them up and repair the ducts work for our AC system and while I'm solving that issue I plan on addressing the heat issue too.
The room is heated by one single pipe radiator which is oddly placed pretty far about 15' away from the actual riser from the basement. I've not yet opened that part of the knee wall but I believe that the pipe just runs along the floor and is pitched the wrong way as it bangs a bunch in the beginning of every cycle.
At minimum I plan on moving and re-piping this radiator and moving it to be closer to the riser since it's location really doesn't make much sense where it is.
I also plan on adding better insulation when I have all the knee walls open. The issue is I'm not sure that these things will actually be enough to fix the general issue.
With that said this will be a pretty sizable project and so I want to just do it once. Here's my worry, I will be improving some of the insulation but the general ceiling is going to stay somewhat poorly insulated and I'm not really sure how much of an improvement insulating the knee walls will really make. Additionally the radiator does get heat it's just noisy so I'm not sure if moving it will actually make the room heat that much more/faster once it's moved I'm mostly just addressing the noise issue.
My thought is to do one of few things I'm considering:
1. Move the radiator, fix the slope on the piping and add better insulation in the knee walls (least effort)
2. Move the radiator, fix the slope and insulation and also add a second radiator (medium effort)
3. Remove the radiator entirely run an hePex hot water loop off the boiler and do radiant walls with a separate tstat (most effort)
I lean toward #3 largely because this room often needs heat long before the thermostat in the lower level calls, and generally looses heat very quickly, having a separate thermostat would solve that issue but also better insulation might minimize some of that problem.
# 2 might help the room recover more quickly in the evenings when the boiler is running more often but during the afternoon and evening when the boiler doesn't need to run it would still get cool.