Upgrade to 16 seer in new build? (how much, homes, cost)

[Ponderosa]

Don't believe the post about SEER does not matter. The relative improvement is realized at all temps. In English: the 16 SEER is more efficient than the 14 at any temperature and humidity combination. In my own case, I went from a 12 to a 16. My amp draw is 30% less than it was on the old unit regardless of ambient temps (well, I only amped it before and after at 105 ish where it was 30% less with the new unit than it had been a couple hours earlier with the old one) My cooling costs (summer bill) dropped by 25% after the changeover resulting in my budget payment dropping significantly.

[slo1318]

Originally Posted by dadof2divas

R19 wet spray cellose in walls with R30 in ceilings. Glad to know it will be money well spent!

Id say the walls are fine, but I would upgrade the attic.
If they had a spray foam roof option that would be best, but upgrading to at least R40 on the attic floor would help too.
Also with a 16 SEER system, you should have a variable speed motor, as opposed to all on all off.

[wit-nit]

We have an older home. We changed out a 10 seer Carrier for a 19 seer Trane. we noticed immediate difference in savings, nearly 50% in the utility bill and the efficiency is unbelievable.
Going from 14 to 16 will save you the extra cost the 1st year easily.
Check your utility company for rebates also. When we did ours, APS had a $300.00 rebate at the time.

[Zippyman]

Originally Posted by Ponderosa

Don't believe the post about SEER does not matter. The relative improvement is realized at all temps. In English: the 16 SEER is more efficient than the 14 at any temperature and humidity combination. In my own case, I went from a 12 to a 16. My amp draw is 30% less than it was on the old unit regardless of ambient temps (well, I only amped it before and after at 105 ish where it was 30% less with the new unit than it had been a couple hours earlier with the old one) My cooling costs (summer bill) dropped by 25% after the changeover resulting in my budget payment dropping significantly.

24% less amp draw isn't even possible at that temperature, unless your new unit was a 2-speed compressor, on the low stage, and then it wouldn't be providing the same amount of BTU.s,

or,

your old unit was failing/improperly charged/improperly installed -

hence the replacement of the unit.

I can send you data sheets for compressors that show one amp difference @ anything above 95 degrees between a seer 13 and a seer 18 unit. That's 9% tops, for an upgrade cost of $1500 - $2k+ retail. it'll never pay off - especially in a new energy-star home.

If that home is built to spec and sized @ 1500-2000 sq ft, they would have to leave the windows open in july to get a $300 bill.

[Ponderosa]

Originally Posted by Zippyman

24% less amp draw isn't even possible at that temperature, unless your new unit was a 2-speed compressor, on the low stage, and then it wouldn't be providing the same amount of BTU.s,

or,

your old unit was failing/improperly charged/improperly installed -

hence the replacement of the unit.

I can send you data sheets for compressors that show one amp difference @ anything above 95 degrees between a seer 13 and a seer 18 unit. That's 9% tops, for an upgrade cost of $1500 - $2k+ retail. it'll never pay off - especially in a new energy-star home.

If that home is built to spec and sized @ 1500-2000 sq ft, they would have to leave the windows open in july to get a $300 bill.

A scroll itself pulls 15-20% less amps per ton than a reciprocating compressor (roughly 5 versus 6-8). Add in PSC and EC fans (part of what is needed to get to SEER 16) and you get that kind of savings.

[Zippyman]

Originally Posted by Ponderosa

A scroll itself pulls 15-20% less amps per ton than a reciprocating compressor (roughly 5 versus 6-8). Add in PSC and EC fans (part of what is needed to get to SEER 16) and you get that kind of savings.

You aren't measuring the amp draw on a psc motor *in an air handler* when you are checking the amp draw at the condenser. And don't tell me this is a package system, because your amp draw is too low for that. A three-ton 13 seer scroll will pull 11 amps @ 95 degrees. A three-ton 18 seer scroll pulls 10 at the same temperatures ( in high speed ) your amp draw readings are wrong, or that system that you measured was in low speed.

In any case, if the op takes your advice, they aren't going to "save" 25% on their cooling bill. I'm so cheap I squeak, and I wish it really was that easy to cut your bills, but it isn't. If the op's house is built to spec, they'll have a tiny bill with either system, but not because of the seer rating of the Hvac system, because the house is properly sealed and insulated.

[dadof2divas]

We are going to upgrade the ceiling to R38 since that is all they will go up to and that is going to run us around $300 for that upgrade. Now the house size is 2550 sqft. It is a ranch and it will have 2 units and 3 thermostats. Since the house now has 2 units the upgrade to 16 seer from the 14 seer is going to cost us $900 for both units. Now I have to rethink it. I know the attic is a upgrade but not sure on the other. The house is already energy efficient which is a good thing. I just don't want to spend money on this type of upgrade if it isn't needed. And if it matters or not the units are Trane units.

[observer53]

2 units for a one story 2500 sq foot house??? I don't think I'd spend the money to upgrade the units, but I'd go for the insulation.

[jimj]

Originally Posted by observer53

2 units for a one story 2500 sq foot house??? I don't think I'd spend the money to upgrade the units, but I'd go for the insulation.

Agreed! Also as someone who's bought an "energy star" rated home before and found out what that means in real life I do have a suggestion for you. Ask to see the blower door tests for YOUR house.
Our house had a power usage guarantee, they certified that it wouldn't use over xx amount per month because it was "energy star" rated. Well come to find out that in order to get that rating they test ONE house and then are supposed to build each house that exact way. They didn't take into account how the house was placed or sun exposure, things like that make a difference.
They don't test each house. Our house and a few others had issues with cooling and it was found after several months that they made a big error. When we finally got 'em to actually test our homes they did not meet the original certification and on one house they actually had to rip out and replace both a/c units with much bigger ones and on others had to add diverters in the ducts to balance the system.

[ReadyFreddy]

I wouldn't do the insulation, either. The SRP site says you can save UP TO $25/year by upgrading your insulation, or some such tiny value.