Efficient HVAC for small apartment
I have a 500 sq ft garage apt with 20+ year old central electric heat and AC that I want to upgrade to a more efficient system. Since it has two rooms and ductwork, I’m thinking a mini-split is not the best option. I now have natural gas and could put in a 95% efficient gas heater (more efficient than electric heat of any kind I think). A 1 ton AC unit seems like a good option for cooling but I can’t find one, only a single stage 1.5 ton unit which is overkill. My nephew is an HVAC installer in Texas and he has recommended a 2 stage 2 ton unit that will act as 1.25 ton in lower stage. Is this the best we can do? I live in Baton Rouge, Louisiana in a very moderate climate. Thanks for suggestions!
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Replies
If you have natural gas sounds like a good plan. If you have low electric rates, a mini split would work well too.
Dorothy,
One option is a ducted minisplit.
If efficiency is your goal and a/c is the major load a minisplit is definitely the way to go, either ducted as Martin suggests or with a low-wattage circulating fan installed in a stud cavity between the two rooms. A 2-ton unit even on low load setting is way overkill.
Thanks for advice on nixing the 2 ton AC. Can you provide me with some information on how you attach a mini-split to ductwork. I haven't seen that application.
Dorothy,
Here is one brand of ducted minisplit:
http://mitsubishi-minisplit.com/mini-split-concealed-duct-systems/
Thanks so much Martin and others! After talking to products rep it sounds like ducted minisplit will work best for my situation. I will probably end up taking all old ductwork out and putting in 2 new short ones which will also reduce loss in many feet of ducts I have now. Rep is going to call me back with the appropriate unit size for my place. I've been struggling with this for 2 years so I'm thrilled to find this resource for "green" information.