I would like to see all model numbers.

Not impressed with size of returns...need to be larger...

Looks like you are going cheap over comfort.

Single stage vs two stage furnace and condenser is more about comfort and cost rather than reliability.

"I am considering the following to add to the new system: Start Assist Kit, 5-Minute Time Delay, Surge Protector."

Surge protector maybe. I would rather put this money toward a better system.

I ave always been told for conventional systems in Texas, 80% eff nat gas furnace with AC was preferred system. You do want a high eff blower at the minimum with furnace you select. Two stage var speed preferred.

IMO

Do your own free whole house load calc a number of times until you believe you have ballpark numbers. Follow instructions to he letter (EASY).

I am thinking a 3.5-Ton system might handle things better for humidity control, plus a better fit with the duct system...

You don't want any oversizing in Houston's climate or it won't control the humidity.

Always oversize the filter racks; it will need two large filter rack areas, so there is less than 300-fpm velocity through each filter.

Also, need to have the system's "delivered Performance should be checked to verify the install.

Here is a link that might be useful: free whole house load calc

Hi Tiger,

Appreciate your response. Carrier model numbers are:
Condenser: 24ABC648A003
Evaporator: CNPHP6024ALA
Furnace: 58PHA090-1-16

Honeywell, Vision Pro8000, TH8110U1003 included in bid.

After your response, I will look into Carrier Performance and Infinity series. I am hoping Carrier is a reliable brand?

As per your comment, I will look into two-stage but since I'm a novice, it is a learning curve.

I would change thermostat to Carrier's Performance Edge Thermidistat.

You want a whole house media cabinet.

Not top of line but with these changes, not a bad system at all.

IMO

Hi Tiger,

Re: whole house media cabinet:

Included in quote was Honeywell Whole House Air-Cleaner on each system (model F100F). Is this the same as a "whole house media cabinet?"

Are you indicating that Carrier Comfort series is okay if I add media cabinet and Thermidistat? Or should I continue to explore Performance series?

An oversight on my part. Get the F200 HW filter cabinet. Cost difference minimal.

Go with the Edge thermidistat. Should help you on AC dehumidification. Expect to pay more.

After thinking about the AC condenser, I would consider the Performance 16 AC model. Much quieter and a nicer cabinet.

http://www.carrier.com/homecomfort/en/us/products/heating-and-cooling/air-conditioners/split-system-air-conditioners/product---split-system-air-conditioners---24acc6/

Finally, I would look at enlarging those returns.

Otherwise a good middle of road system.

IMO

Here is a link that might be useful: HW F200 Media Cabinet

This post was edited by tigerdunes on Tue, Dec 10, 13 at 15:08

Hi UDarrell,

Re: Always oversize the filter racks; it will need two large filter rack areas, so there is less than 300-fpm velocity through each filter.

What is a filter rack? You're above my head on 300-fpm velocity through each filter but I will ask the a/c company about this.

I also did a whole house calculation but don't really know what the results mean. Will also ask the a/c company about this, too.

ACCA Manual D, requires 'that' sizing of the filter area for the cheap fiber-glass throw-away filters; also a good way to go for most other filter's except the real deep pleated filters.

They will tell you that is not important; but it can make a big difference in airflow & better filtration.

Search: Hart & Cooley engineering Design for sizing Return Air filters; on their charts (Ak) means sq.ft., of Free-Air-Area...

A filter-rack is like a return air filter in the ceiling with a grille over it; or two separate ductwork filtered drops to the Return Air blower chamber.

It is good efficiency design for anything requiring above 800-CFM of airflow, or anything above a 2-Ton A/C.

There are also a number of ways a good tech can check the "Delivered Performance" of an A/C or Heat Pump; this should always be done; otherwise you don't know what performance you have, or the level of performance you paid for & didn't get!

Far too many don't know how to do it any of those performance checks; it's the only way you know what your getting....

I can even tell you various ways you can check your A/Cs performance just using a low cost indoor humidity gauge & a good low cost 'preferably' digital thermometer.

Here is a link that might be useful: Checking duct airflow and equipment performance