You are right! Before installing a whole house dehu, size the a/c to handle peak load. Close sizing means less supplemental dehu needed. Extra capacity for parties or set-up t-stat for rapid cool down means more supplemental dehu, but let the customer deside. Next eliminate as much duct leakage as possible. Lastly, set the air flow volume for proper coil temp to remove as much moisture as reasonable for good distribution, without making the ducts sweat or freezing the coil. The colder the coil the lower the SEER. This setup on good a/c installation should provide <50%RH on a hot day. Now if concerned about fresh air ventilation, maintaining <50%RH for ideal comfort, minimizing cooling cost with no a/c when unoccupied, and avoiding mold/dust mites, during the low/no cooling load time, supplement with a whole house dehumidifier.
Originally posted by beenthere
Teddy, my point is that your answer to everybody is a whole house dehumidifier.
In one post, the guy has 2 new systems over sized for his house by perhaps more then a ton, and your answer is install a whole house dehumidifier.
Shouldn't the answer be, have the contractor install the correct size units?
Not put a band-aid on it.