New System Advice

[smog tek]

Newbie here.

First off, I've got to say I love the ductopus' you guys have posted and am happy to report I don't have one in my attic!

Just recently found the forum while researching for a replacement central air system.

I've got a 2637 sq ft 2-story home in the California desert. Highs in the summer average @ 105 and push my electric bill to unheard of highs.

That said, I'm getting reading to replace my 22 year old Carrier 5-ton, 10 SEER system. The current furnace is a Payne that was installed 4 years ago to replace a recalled furnace that burned down a few of the homes in our tract.

I've got a quote for 3 Carrier options:

1) 5-ton, 15 SEER Performance 24APA560A003 (Puron) with evaporator and programmable t-stat.

2) 5-ton, 14 SEER Comfort 24ACA460003 (Puron) with evaporator and programmable t-stat.

3) 5-ton, 13 SEER Builder 24ABA360A003 (R22) with evaporator and programmable t-stat.

All 3 options include:

1. New sheet metal supply plenum.
2. New refrigerant, drain and electrical connections with a new fused disconnect.
3. Replace deteriorated flex duct.
4. Remove old furnace in attic.
5. Labor.
6. Start-up.
7. Removal and disposal of the old equipment.

I'll be here at least another 4-5 years and my wife's comfort is the #1 priority.

I've ruled out the Builder and am leaning toward the Performance as the cost difference between it and the Comfort isn't that big a deal.

Considered Infinity, but contractor said running on high would essentially bring the 21 SEER down to 15 anyway, so 15 would be best.

Given the high summer temps here I don't know if the system would ever get off the high speed or not.

Questions:

Does the Performance sound like a good system for my application?

Or would the Infinity be a better option?

TIA for any input,

Matt

[hvacrmedic]

Newbie here.

First off, I've got to say I love the ductopus' you guys have posted and am happy to report I don't have one in my attic!

Just recently found the forum while researching for a replacement central air system.

I've got a 2637 sq ft 2-story home in the California desert. Highs in the summer average @ 105 and push my electric bill to unheard of highs.

That said, I'm getting reading to replace my 22 year old Carrier 5-ton, 10 SEER system. The current furnace is a Payne that was installed 4 years ago to replace a recalled furnace that burned down a few of the homes in our tract.

I've got a quote for 3 Carrier options:

1) 5-ton, 15 SEER Performance 24APA560A003 (Puron) with evaporator and programmable t-stat.

2) 5-ton, 14 SEER Comfort 24ACA460003 (Puron) with evaporator and programmable t-stat.

3) 5-ton, 13 SEER Builder 24ABA360A003 (R22) with evaporator and programmable t-stat.

All 3 options include:

1. New sheet metal supply plenum.
2. New refrigerant, drain and electrical connections with a new fused disconnect.
3. Replace deteriorated flex duct.
4. Remove old furnace in attic.
5. Labor.
6. Start-up.
7. Removal and disposal of the old equipment.

I'll be here at least another 4-5 years and my wife's comfort is the #1 priority.

I've ruled out the Builder and am leaning toward the Performance as the cost difference between it and the Comfort isn't that big a deal.

Considered Infinity, but contractor said running on high would essentially bring the 21 SEER down to 15 anyway, so 15 would be best.

Given the high summer temps here I don't know if the system would ever get off the high speed or not.

Questions:

Does the Performance sound like a good system for my application?

Or would the Infinity be a better option?

TIA for any input,

Matt

If comfort is your goal, then get the Infinity. Your contractor was misinformed. The SEER isn't fixed, and you probably won't get 21 SEER out of it, but the same applies to the 15 SEER system, and high and low speed operation isn't the deciding factor in this.

[beenthere]

OD temps exceed 95*.

Find out which system gets you the higher EER.
SEER doesn't mean a lot for your OD temps.

[smog tek]

So the Infinity system, rated at an EER of "up to 14.5" is the better choice compared to the Performance rated at "up to 12"?

I'm only guessing, but it would seem the higher efficiency rating would result in the greatest cost savings electricity-wise.

Question: Are SEER/EER ratings similar to EPA mileage ratings in that "your mileage may vary according to driving habits"?

Thanks,

Matt

[beenthere]

That about it.

But don't go by the up to.
Find out the rating for the model you are being sold.
5 ton units, seldom get close to the higher, up to ratings.

[hvacrmedic]

So the Infinity system, rated at an EER of "up to 14.5" is the better choice compared to the Performance rated at "up to 12"?

I'm only guessing, but it would seem the higher efficiency rating would result in the greatest cost savings electricity-wise.

Question: Are SEER/EER ratings similar to EPA mileage ratings in that "your mileage may vary according to driving habits"?

Thanks,

Matt

The listed EER doesn't depend on any of your habits. It's the instantaneous efficiency under specific lab conditions. It's a truer measure of efficiency in areas where dehumidification isn't necessary and where the average heat load is high. SEER is an adjustment to EER that takes cycling losses and average EER throughout the season into consideration.

EER per se can and will change with changing temps, and the extended performance tables for the unit will usually give the EER for all rated match-ups over a wide range of air volumes and temperatures.

In your area EER is more reliable indicator than SEER.