help with Manual J for ductless splits
I’m trying to do a room-to-room Manual J using Cool Calc so I can size a ductless split system at my house. The inputs that I’m having trouble with are walls and hot water pipes. The house is wood framed, it was built in 1925, and it has a hydronic radiator system (baseboard radiators on the first floor; upright cast iron radiators on the second floor). But for example, Cool Calc wants to know if the walls have cavity insulation or board insulation, and whether the walls are 2×4 or 2×6, but I have no idea. Similarly, Cool Calc asks for the following about the hot water pipes: type of metal, length, thickness, insulation, ambient temp, and hot water temp. I don’t know the answer to most of these questions. As a WAG, I put: steel, 50 feet length, 2 inch thickness, not insulated, ambient temp 40F, and hot water temp 180F (mainly because these two were suggested as default temps). But again, I don’t know how accurate this is. Besides tearing up walls all over the house, is there any way to arrive at a more informed guess about some of these inputs? Thanks.
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