I'm in process of designing and sizing a cooling setup for my house - 2400 sq ft, three floors in Massachusetts. Built in 1871 with original single plane windows with storms. Dense pack cellulose in first and second floor walls, but no insulation in the third floor(mansard roof) My current plan is to have a single high static concealed ducted unit for the first floor (800 sq ft, mostly wide open space with wide pocket doors between rooms) Then for the second floor(also 800 sq ft) - two low static concealed duct units for two bedrooms(about 250 sq ft each) and then one regular wall unit for the smaller(130 sq ft) office. No cooling on the third floor for now(probably a separate mini split with ceiling cassettes eventually) I have hydronic heat, so I'm not really concerned about the heating portion of the mini splits. I may only use them during shoulder seasons. I have performed Manual J calculation and I'm coming with about 31000 BTUH cooling load and 65000 BTUH heat load(with heat load matching my previous heat load calculations for my constant circulation radiator heat) 1) I'm curious about how do those numbers sound. Really don't want to oversize, but I would also like to avoid undersizing. 2) For cooling design temperature the default seems to be 75 degrees. I also understand that manual J is a calculation for the worst case scenario. But I like it to be cool in the house(more like in 68-70 degrees) If I change the design temp to 70, then the load goes way up into 40s. I'm thinking that the system should accommodate my 70 degrees requirements on most cooling days. Any thoughts? 3) Concealed duct units are somewhat rare, but I have few ideal spots to install them so I really like the idea. Any input/tips on reliability/etc for those units? I will be probably going with LG multi F system. Thanks in advance!!!

The outdoor unit is working perfectly. When I turn the cooling on, everything starts up fine. When it cycles off and back on again, the blower motor doesn't start back up with it. So I'm turning it off myself and waiting a while to turn it back on. After turning the cooling off, nothing will start again for 3-6 hours. Turning the cooling back on yields no result. No compressor, no blower fan. Turning just the fan on has the same effect, nothing. I've taken readings with my multi-meter and everything looks normal, but nothing turns on. None of the electrical connections are loose or broken. Transformer is outputting as it should. I'm guessing that the blower doesn't restart with the system because the capacitor is getting weak but I don't understand why it starts after sitting for several hours but not before. Maybe there is a sensor that is keeping the whole unit from starting up. I'm really baffled. Model Unit: Carrier fb4cnf030t00 acaa Any help is appreciated.