hru (heat recovery unit) attached to hvac
I'm in need of installing a new HVAC and water heater and I was thinking of installing a HRU at the same time. I've researched a bit on the web but some of the info is a little old and I've read some people say that with the newer R410 high SEER units, that they don't create enough hot gasses on the return line to make the HRU work effectively but the HRU rep I spoke with said that they all generate a temperature of around 160 degrees on a 90 degree day (we hit high 90's to over 100 on a regular basis in North Florida). I've also heard that cooling the returning refrigerant can possibly cause problems because the heat pump expects a certain temperature coming back to work right. I'm not familiar enough with HVAC to know what is real and what is myth when it comes to these claims but it seems to me that there has to be a good way to make the best use of heat being pulled out of our houses instead of just warming outside air. The air handler and the water heater are basically right next to each other in the garage.
My house is 3000 sq ft. single story requiring a 5-ton HVAC system and I'm deciding between a 17 SEER and a 15 SEER. Some people have told me that it's very difficult to actually get above 16 SEER with a house this size and the price difference between 15 and 17 is pretty big. I'm leaning towards a 15 SEER if I can also utilize an HRU.
Does anyone here have thoughts, experience, or advice to share on this matter?