Central Air Conditioning - Duct vs. Split System

I would go with Duct all the way! Thanks for the post! I look forward to reading more articles and posts that you write in this forum.

SEER rating is the efficiency of a given condenser, all other things being equal. For instance, a 17.0 SEER outdoor unit might be $800.00 more than a 13.0 SEER unit, but overtime its higher efficiency will theoretically earn back the difference and more.

The brand of equipment is pushed by the provider, as each shop claims the brand they rep for is the only good, decent, etc.

Though you didn’t say, it sounds more like you own only this floor? If that’s the case, a Sanyo multi-split unit drives up to (4) air handlers, and the sum of the indoor ratings can exceed the outdoor’s BTU’s on the inference that not all will call for cold simultaneously. For instance a 33K outdoor could drive an 18K, and three 9K indoor units. if they all simultaneously called, each would put out a diminished amount of cold, but you should be fine.

Question is condensate drainage. Is there unfinished space below you or another apartment? Insatallation requires some number of 3″ diameter sleeves thru masonry, depending on number and location of indoor air handlers.

Conventional system would require boxing or hiding 9″X12″ duct front to back? High velocity would also need trunk duct, maybe 8X8 and both would need inside location for air handler at beginning of duct ( copper tubing runs from outside to air handler), same with condensate down.

Make sense?

I had split units put in my house almost 2 years ago. I live in a 980 sq. ft. row home. I had one unit placed on the first floor and the second in the master bedroom (which can cool the whole second floor).

I love the split units. It takes up no space, was inexpensive ($8k for both units plus I got a $1500 tax credit) and they are quiet. They also function as a heater so in the early Spring/Fall seasons, I can heat just that area rather than turning on the heater for the entire house. They were installed in one day and I’ve had no problems whatsoever.

I’ve been keeping mine running all day/night during this excessive heat and the cost is still minor in comparison to window units.

Best money I’ve spent.

It sounds like you are looking to air condition just the parlor? floor of a house? Or is it the garden apt?

Construction considerations trump all other factors when making a decision like this. This more so than strict efficiency, as you cannot compare apples and oranges.

Both conventional HVAC and mini-splits can be ordered with high SEER ratings. Comparing prices usually means the lowest SEER.

Aesthetics also trumps pure efficiency. Mini-splits will have what some consider ugly air handlers in the rooms that they cool. These same mimi-splits allow placements in older homes that traditional central air can only achieve with major surgery for running ductwork.

The mini-splits require small diameter copper tubing that can go up and down, but also condensate tubing that is gravity only, and must go down only. The air handlers do NOT have to be on outside surfaces, as long as there is that downward slope to outside or plumbing wastelines.

To add to the decision, also consider high efficiency Unico style high velocity systems. These are closer to central, but the ductwork is much smaller, sometimes pullable in existing walls, closets etc.

Unless this is the only floor you own, I would recommend a strategy that anticipates air conditioning other floors, even if that part of your project isn’t completed now.

Efficiency is complex to consider. For instance there is the measure of how efficiently the condenser is able to convert electricity to cold. Seems important, but it is hardly the end of story. Sometimes a more clever delivery of cold to the locations that most need it is far less expensive to run.

Siting of the outdoor components can eliminate one or the other systems from consideration due to permitting and regulations.

bruce at jerseydata.net