Quote:
Originally Posted by ithos
Yes it does. So I guess there are problems if you oversize the compressor due to minimum speeds limits since it may make it more difficult at times to achieve the target SHR (Sensible Heat Ratio). I had to look that term up.
Sensible Heat Ratio (SHR) - HVAC School |
And with a single speed system you need to get all these calculations correct but with a Variable speed system like the Trane or Carrier Infinity Greenspeed variable speed systems, it automatically calculates all this real time, all the time. This is why you need to use the Carrier thermostat which they call a "wall unit" since it "controls" the whole system real time. Similar with the Trane.
I think, if you can afford it especially with all the Federal tax credits and instant rebates on the Variable speed systems available right now, you are better off long term with the variable speed system vs the single stage systems since they are more flexible and will adapt to the specifics of your home. What about 2 stage systems? They are good as well but I believe you will find they are not that much cheaper than the Variable speed units with the credits and rebates available right now. After 2025 when the 25C Federal Tax credits go away, then we will have to re-think what's best at that time.