4 ton or 5 ton A/C what's the difference? (furnace, windows, air conditioning)

[eyewrist]

I will be purchasing a new AC and furnace to take advantage of rebates. But I don't know the difference between 4 and 5 ton. I live in Texas and it gets hot for three months out of the year but I will also have sprayed insulation in the attic with the possibility of radiant barrier also installed depending on the price of the barrier. Can anyone assist? Thxs in advance for your input.

[Charles]

One ton of air conditioning is the equivalent of 12000 British Thermal Units (BTU). Essentially, a five ton AC is 25% more "powerful" or cools more than a four ton AC.

Did you have a Manual J calculation performed? This is the best way to determine the correct sized AC for your home. A lot depends on orientation, windows on different sides of the home, latitude.

This is a big decision. Don't "wing" it. Especially in humid Texas where having too big an AC may not remove the humidity in your home. Make sure a qualified person sizes your home properly. Perhaps get three estimations (if they are free).

[al_roethlisberger]

Concur: Get a heat loss/gain calculation done on your home and have the unit properly sized. An oversized unit can cause just as many problems in different ways as an undersized system, including and not limited to higher operating and increased repair costs due to issues such as short-cycling.

Although not just A/C specific, here are two short and humorous essays on the downfall and advent of oversizing systems:

Heating Help (http://www.heatinghelp.com/article/11/Hot-Tech-Tips/221/Oversized-Heating-Equipment - broken link)

Heating Help (http://www.heatinghelp.com/article/11/Hot-Tech-Tips/144/Boiler-Sizing - broken link)


Once you get the pros to accurately determine your actual cooling needs, you may be pleasantly surprised that you don't need as large a system as you once thought.


Good luck!
Al

[eyewrist]

Thxs for the info. I will get the 4 ton with the insulation done also. I was also told the rebate applies to only 16 seer system which can be costly.

[al_roethlisberger]

Originally Posted by eyewrist

Thxs for the info. I will get the 4 ton with the insulation done also. I was also told the rebate applies to only 16 seer system which can be costly.

Not to belabor the point, but did someone spec the 4 ton based on an actual cooling load/heat loss calculation?

I really do see some old timers say things like, "well, you have 2200sqft and all my years tell me you need 4 ton", but don't take into account the new tech, insulation, etc.

I'd get a couple/three calculations done and hopefully they'll all be close. If not, I'd ask questions why.

I'd also suggest doing some individual research into pricing and rebates for higher SEER units. When we installed our 15ish SEER unit a couple years back, it was not significantly more expensive than the 13 SEER option.

Any pro worth their salt will be happy to do heat loss/cooling load calc for free or a small fee as part of the estimating process. If they refuse, I'd think about sending them on their way.

Good luck!
Al

[Charles]

Originally Posted by eyewrist

I was also told the rebate applies to only 16 seer system which can be costly.

While the SEER 16 may be more expensive than a SEER 14 for example, depending on you electricity rates, the breakeven point might not be that long. In Huntsville, our electricity is cheap, like $0.09/kwhr. Back where I lived in Los Angeles it was between $0.15 and $0.25 so a high SEER AC would be a good idea in LA.

[eyewrist]

Originally Posted by al_roethlisberger

Not to belabor the point, but did someone spec the 4 ton based on an actual cooling load/heat loss calculation?

I really do see some old timers say things like, "well, you have 2200sqft and all my years tell me you need 4 ton", but don't take into account the new tech, insulation, etc.

I'd get a couple/three calculations done and hopefully they'll all be close. If not, I'd ask questions why.

I'd also suggest doing some individual research into pricing and rebates for higher SEER units. When we installed our 15ish SEER unit a couple years back, it was not significantly more expensive than the 13 SEER option.

Any pro worth their salt will be happy to do heat loss/cooling load calc for free or a small fee as part of the estimating process. If they refuse, I'd think about sending them on their way.

Good luck!
Al

I have a couple of more bids coming in and I will ask them but the previous one didn't discuss that with me.

[eyewrist]

Originally Posted by Charles

While the SEER 16 may be more expensive than a SEER 14 for example, depending on you electricity rates, the breakeven point might not be that long. In Huntsville, our electricity is cheap, like $0.09/kwhr. Back where I lived in Los Angeles it was between $0.15 and $0.25 so a high SEER AC would be a good idea in LA.

Here in Texas it is in the range of 0.11 to 0.12/kwhr depending on the company you go with and what plan you choose.