New home heat pump
 

We have a newer home in ST Catherine and when I looked at the heat pump they put in, it looks like it is undersized for our house sq footage. We have a 2038 sq ft house with a 3 ton heat pump and when I check on many sites online, the right size for a 2000 sq ft house is a 4 ton heat pump.
Has anybody else ran into this and if so, have you brought this up to the developer?

The rule of thumb is about 600 SF per ton. 3 tons is about the correct size. I think 4 tons would be oversized.

Duuuuuuuuude: = 600 + 600 + 600 = ______

The rule of thumb is a rough estimate. 3.5 tons may be closer to the correct size. But, unless there is a cooling issue, I don't think the builder will change it out. I haven't seen any cooling issues in The Villages.

My new home is 33% bigger than my old home, and the heat pump is 33% smaller. The new homes are so much better insulated than the ones built even 15 years ago and don't require the same size heat pump.

We've been in it 4 years and have had no issues, even when it's 100 out.

You should be able to get the heat loss calculation for your home which will have the required size of the HVAC system from the county building department. This should answer all of your questions. Then if the calculation shows a different size, you can call home warranty, to find out who installed it and request the correct sized unit.

I have never looked as it works and my house it cool. Guessing you looked because you have a problem getting your house to cool down. Document the issue and contact the warranty department. If you don’t have an issue cooling your house I would not worry about it.

A heat pump is basically an A/C unit it’s in the winter months is when it changes by taking the ambient heat from the outside air it converts that to heat for the house. Depending on design and efficiency some work well others not. When outside air reaches 32f approximately most efficiently is lost.

My concern is 3 tons might be on the smallish size and it will work harder to cool the house down compared to a larger size which won’t work as hard. I’ll ask Munns who put it in. Thanks

Slightly undersized is better than oversized. Far better to have longer run times versus short cycling. You might consider a variable heat pump if you replace it. I have a Carrier variable speed heat pump that is slightly undersized by performs well year round. As pointed out, get the calcs from the building department and see what they recommend. The size of the unit is just one variable in cooling a home - there are others including supply duct sizing, return sizing, type of inside unit, window sizing and direction etc etc.

⌚
 

as you know your home 1st year warranty is almost up.
There are home inspectors who advertise here on totv.
I also live in st catherine's and will be utilizing their services which i believe would also address yours and the myriad of items us non professionals would obviously miss
good luck.

You nailed it.

Also oversized condensers can cause humidity and air quality issues as dehumidification is another function of AC.

If you want to increase your heat pump efficiency, have the spaces above your lanai and garage insulated or have a radiant barrier installed. This will help with your attic temps and take some of the strain off your heat pump.

You will get an answer from them but probably not an objective one because they would have to admit they put an undersized unit in your house. Look at the good news ; you are going to have to replace it in about 12 years or less anyway. As others have stated your A/C works as an evaporator inside your house while it is running removing humid air. I would just relax and enjoy your new home and be more concerned with changing the filter (twice as often as recommended with the exact size replacement)and making sure the condensation drain is flowing properly

You would get better results by adding insulation to the attic spaces above the conditioned areas. Insulating unconditioned areas will not have much benefit. That is why unconditioned areas, like the garage and lanai, are not insulated in the first place.

FYI. Just to keep everyone honest, go online and look for a ( manual J work sheet ) include all the important information and you will have a exact answer! There are no other formulas or way of guessing!!! Although it seems like a lot of people here are HVAC licensed. All guessing ideas are just a guess. Just because 100 of your neighbors have something, doesn't mean that they where done correctly! Manual J doesn't lie!!!!!

2.5 Ton Works Great For 2200 sq.ft.
 

Undersize is best. My immediate neighbor put in a 4-ton. It’s whisper quiet outside, but compressor harmonics make it very noisy in ours and their bedrooms. Hum-hum-hum-hum-hum and is louder when heating. We almost sold out our house due to being unable to fall asleep. …Careful what you ask for.

Manual J is good, but I wouldn't call it an exact answer. It uses several variables, such as number of occupants, and ceiling height. Most houses have multiple ceiling heights, and there are definite differences in the number of occupants. I would think that an over 55 community would have fewer occupants per house than other places. But, it is pretty clear that a 2000 SF house in The Villages does not need a 4 ton heat pump.

Well said. I built a house in Pennsylvania and put R-60 insulation in the attic—much more than what houses have here. I told the HVAC company what I was doing and that the AC size should be decreased accordingly, but instead they put in their usual size. The predictable result: the AC would run a few minutes, quickly cool the house, then turn off, but it didn’t run long enough to extract much humidity, so the house felt humid. Turning down the thermostat so the AC would run longer just made the house cold and clammy. I had a little gadget installed that fooled the heat pump into running less powerfully but for much longer, and that solved the problem. But it cost $1,000 installed. Running longer with a smaller but more efficient heat pump is much more cost efficient for you and yields better cooling with less humidity. Chances are, your smaller unit is the right one for your house. My home here in The Villages is 24 years old and has much less insulation than I’d like, tramped down by workmen over the years, but from April to November I keep the AC on at all times, set at 74°, and never leave doors open. My electric bills are remarkably low, I think. While I could have more insulation blown in, I think it would take a number of years to recover the cost.

Humidity is a major issue here. A larger unit will have shorter run times and, therefore, will not be as effective in controlling indoor humidity. A slightly undersized unit is better than oversized. As someone else mentioned, an analysis would have been done by the installer to determine the correct size. It may be taped to the air handler. Don’t go by “rules of thumb” on the internet.

New home heat pump
 

I had a smaller home in the villages 1950 sq, and had a 3.5 ton unit in that home. The new home which I have lived in for 3 years is 2350 sq and has a 2.5 ton unit. I asked the company that installed it about this, and they sent me the sizing calculations that are required by the state. The newer homes are built with energy saving in mind, and require less energy to cool and heat. I have lived in the new home for 3 years and the unit has worked just fine and my wife keeps the ac at 74 degrees. All homes built in Fla require that the sizing calculations be done before installing a unit. The installer can not put in a unit then other then what is called for. There are some exceptions where a larger unit is installed, but that is when a unit is installed that runs at multiple speeds so that it is capable of using a low output so that the unit selects the correct speed. It can run longer, which is how you control humidity. An oversized unit will cool the house fast but not get rid of the humidity as well as a smaller unit running longer.

If you get a unit that is too large, it will not long enough to remove the humidity. It is a balance between cooling and dehumidification.

RVJim and a few others here are spot on. You can easily go to the Sumter County website and look at your blueprints and Manual J calculations for YOUR home. A tad undersized is better than oversized for the reasons many have stated. If you cool down the temp in your home w/o allowing run time to get the humidity down you will get what they call, "Meat locker syndrome" and your home will feel cold but clammy. You do not want short cycling. The most common complaint we hear is temperature variations in rooms, which most often caused by poor air balancing and missing/displaced insulation. Hope this helps! Frank D'Angelo , MPI

We have a furnace in our home. Are the newer homes having heat pumps installed instead of furnaces?

Heat pumps are for cooling the home? We have an air conditioner for cooling and a gas furnace for heating. Also add that I'm confused about heat pumps.

Never mind, answered before I posted.

Yes, many or most newer as well as older homes have heat pumps. Our home is 14yrs old (Amelia) and has a heat pump. Basically an A/C that provides enough heat to take the chill off when it goes below 40. Most homes don't have gas around The Villages except for a few areas so all electric.. I wish ours did have gas. Hate electric stoves.

A heat pump is a reversible heating and cooling unit that transfers heat from inside your house to the outside in the summer, and then reverses itself to transfer heat from the outside to the inside in the winter. It's all electric and is very effective in a warm climate like Florida. It doesn't work as well in colder climates.

Think of it like a reversible belt that can be black or brown, depending on what color pants you are wearing.

I think others stated, asked is is working well. Putting in an oversized unit is not a good idea. A major part of air CONDITIONING is humidity control. An oversized unit will not run as much and not remove humidity.

Our previous home, the previous owner put in a way oversized air-conditioner. It was like a cave-cool and damp. We had to replace it.

I agree that you should avoid installing oversized AC unit. However, if you purchase a house with an AC that is too large and does not control humidity adequately without overcooling, you can add a free standing dehumidifier to reduce the relative humidity in the home rather than replacing your AC if it is otherwise working fine.

A free standing dehumidifier reduces the relative humidity in the home two ways:
1. It reduces the amount of water in the home atmosphere by condensing water out on the dehumidifier cooling condenser coils. This reduces the absolute humidity level in the house atmosphere.
2. The dehumidifier produces heat from the refrigeration effect. The produced heat is rejected to the home atmosphere and thereby raises the temperature of the home atmosphere. Relative humidity is reduced when the home atmosphere temperature is raised and reduces the need for overcooling which causes the meat locker feeling.

These combination of these effects should have your AC-dehumidifier combo producing good relative humidity (less than 60%) without having to overcool your home atmosphere by 3 to 5 degrees F. I have used a free standing dehumidifier to control home relative humidity during heavy rainy periods and also as a backup when we were snowbirds. You can get dehumidifiers with pumps to avoid having to manually drain the pans.

These used to cost about $200 but today are probably $400. However this is a lot less than a new AC unit.

Thanks for the explanation.

Thank you for the explanation.