Dreaded Cooling "Rule of Thumb"
Someday, I would like to condition three spaces in my country place in Northern California (i.e., cool nights and little humidity, but occasionally hot afternoons). One area measures 200 sq ft., and the other two measure 300 sq. ft. each. The house has a wrap around porch, so none of the areas experiences any heat load from direct sunlight. The house is well insulated.
While I consider a single supply system (as opposed to separate window mounted units in each area) I have three very preliminary questions:
1. What size air handler might I end up with?
2. Would more than one ceiling register be necessary to supply the conditioned air to each room?
3. If the duct runs to each room are modest (i.e., 10' to 20'), what size duct would likely supply the register(s) in each room?
Just to emphasize, I am not considering conditioning the entire house. I would be satisfied to achieve a modest degree of cooling in just the three spaces in question. For that reason and others, I already know that I don't want to add cooling to my existing furnace/warm air supply system.