I had to replace my old HVAC because it was old and had a freon leak. The new unit doesn't cool down the house like the old system. The ac runs all day and it takes hours to get down to 72 degrees and sometimes it goes up from 74 to 75 with ac running. Outside temps are usually 85 to 95 The old unit within 2 hours house would be cold. Even though new ac running all day I get a similar electricity bill. Is this normal my new ac takes forever to cool the house down?

Thank you

  • hard to know without data on what you had and what you replaced it with. As a gross general rule though, newer HVAC systems use refrigerant that is less harmful to the environment than Freon was, but is not as effective. So that might be part of it. But it could also be something as simple as a setting or an issue with the air circulation.
    – JRaef
    Jul 3, 2019 at 21:52
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    "Less efficient freon" doesn't make much sense. .. it's simple math of watts in * efficiency = BTU/hr out. The working fluid cannot matter. I suspect this is a sizing issue; the new unit has less BTU/hr. Either it is correctly sized for modern design engineering, or someone messed up, or someone chintzed out. Efficiency is only going up, so if watts are really the same, there must be a problem. Jul 3, 2019 at 22:18
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    Newer refrigerants are, in some ways, more effective than older ones. Typically more efficient and less refrigerant required. I agree that it's probably a sizing issue, or possibly a loose duct or stuck on first stage. Jul 3, 2019 at 22:32
  • The new refrigerant R-410A is more efficient than the old R-22. The R-410A cycle does operate at higher pressure, but the pressure difference between the high and low sides is not higher and this coupled with the thermodynamic properties results in higher efficiency. R-410A is also much less harmful to the environment. Jul 3, 2019 at 23:16
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    Get a competent tech to check the unit. Jul 4, 2019 at 0:40


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