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Join Date: Jul 2000
Location: Houston, Tejas
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Quote:
Originally Posted by mattdavis11 View Post
The unit was replaced, you had me thinking delta T by replacing the condenser coils, leaving the compressor alone. The dual compressor units do cost a lot more, but they will pay off eventually.
My new units are 13 SEER unit. The dual compressor units are 16-21 SEER. They will use 19-39% less energy. But the installed cost for 2 units will be around $15-20K. You have to replace not only the condensor, evaporator and entire air-handler, but also install new controls which work with the 2 stage compressors. The savings on a 21 SEER unit would be about $328 per year over the 13 SEER unit.

The best I could do without replacing the air handler and evaporator was 15 SEER. This could have saved 13%, but would have cost about $1000 more per unit. The savings? About $115 per year.

Even if you just look at the delta, $12K-17K, the extra savings per year of 21 SEER over 13 will take 25+ years, or longer than the life of the unit. If I lived someplace where electricty was $0.30/kWh, it would be a different story: 7 year pay back.

I amlooking to install a separate unit for our master bedroom. I found a 15 SEER 1.5 ton RHEEM R410A for under $1900. I should be able to get it installed for around $1K. This will allow us to run the bedroom as a separate zone from the rest of the house. I like it cold in the bedroom at night! But I also like the idea of having a small unit which my generator can handle, in case we have a lengthy power outage. The savings will not pay for the unit.
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Old 09-30-2011, 06:20 AM
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