Air conditioning questions
I have been getting quotes for a new heat pump ac. The problem I’m having is no one can explain to me how new ac with higher SEER can actually save money. It’s more energy efficient, uses less energy, saves you money, is the common response but I just wanted to know how it does this. I would In Phoenix there is an average of 110 days with a tempature above 100 degrees and 33 of those are above 110 degrees. I do not see how the SEER rating is an accurate model for Phoenix. The EER should be more accurate but even then I don’t know. So I tried to figure it out myself but the numbers don’t add up. This is what I did. Volts x amps= watts x hours ÷kw to get kwh. I’m probably wrong but it work for my current ac. Goodman 12 seer single stage 230Vx14.1(rla)=3243 230Vx0.9(fla)=207
3450Wx11(hour)
37950W÷1000=37.95kwh
Last month my energy consumption is 30-40kwh more per day. The new ac fla is between 14.6-17.4 which would all use more electric. I can get goodman gsz14 $5600, ruud rp15 $6600, trane xr17 $9100. If I pay $3500 more will I even get that money back. I thought even a 14 SEER would save me money but I don’t know. “If it ain’t broke,don’t fix it” but it’s 18 years old and I’m not going to pay to fix it. I just want to be prepared when it does. Thank you for your comments, opinion, and advice
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Replies
There are so many factors to consider when looking at energy savings with an HVAC system. Here are a few:
1) Proper system sizing.
2) Properly designed and installed/sealed ductwork.
3) Insulation and air sealing of your house.
4) Efficiency ratings of the HVAC system.
Putting all your money into any one of these things is likely to yield poor results if the others are not addressed as well. Alternatively, investing a bit in each of these, even if you don't end up with the highest SEER HVAC, may work out the best for you.
My suggestion would be to find a contractor that would look at your house as a system and help you spend your money on the best combination of things to improve your overall efficiency.
Thank you for responding. My plan was to do it in phases 1. Solar 2. Insulation 3. Windows/doors 4. Water heater 5. AC/ducts. 4 and 5 were last because they still work. I just don't think my ac is going to make it another summer and wanted to be prepared.