Lovely, a typo in the title.

Additional info, we currently have a 4 ton unit and 100,000 BTU furnace.

couple of questions.
1) why are they flushing the existing lineset instead of replacing. That's not the best situation, as a new lineset can assure that there is no residual oil or freon in the line to cause problems. I recommend a new line set with any options. This should not be a large cost. Maybe $400

2) how long do you think you will be in the home?

3) is there a reason you are not looking at heat pumps?

4) The quality of the installer will be the most important factor in you satisfaction and life of your system. Are you considering other bids?

5) Is flex duct common in an installation such as yours in your area?

6) are you close enough to the ocean to look at coil coatings to help avoid corrosion?

On the whole, I like the second option best of these 3. The staging gives you better filtration options and humidity control capability. Best bang for the buck IMHO

Thanks for responding!

1)why flushing? I suppose it's cost savings but I'd have to ask. I'll speak to him about that.

2)not planning on moving within the next 10 years but who knows what's down the pike. DH works for railroad and seniority moves are possible, especially when the kids are older.

3) Consider heat pumps? I've read very little about them. Not a commom installation in my area but that doesn't mean anything when you're talking builder grade. We have NO idea what's involved in installing that.

4) Quality is definitely a consideration for us. This company is local, in business for a long time, and used throughout my community, and highly recommended. I've contacted other companies, but they did not show up for appts. It sounds lazy, but I'm glad SOMEONE thought my business was worth keeping their appt.

5)Flex is very common. We're soley attic installation due to slab only foundations and past building practices. Have never been in a house with soffits for duct work, not that it isn't used somewhere.

6) We're about 25 miles away. Judging by the state of our current system, corrosion isn't a big issue.

Humidity control is a huge issue here. For the record, our current unit does a fine job of that and it's single stage and OLD. I've never felt uncomfortable when it's running and I'm a big wimp as far as that's concerned. Grew up in Missouri and not a fan of the summers here, especially since I'm a human space heater. Lived in KCMO before we moved here for DH's job, as a matter of fact. I miss home!

Thank you for your opinion. I really like the idea of 2-stage for the efficiency and weather here.

Well, at least in Texas they do have BBQ too!

On the lineset. Technically they can be flushed out, and when done correctly this will pose no problem. But if you can easily get to the space to put in a new one, I feel that offers some peace of mind. Now if they simply can't get to it easily, then you will have to trust them to flush it out.

I would feel that with 10 years you will get the return on investment on any of these systems.

Heat pumps basically use the AC "in reverse" flow to pull heat from outside and use it to heat the house during mild cool weather (65-40ish). It is more energy efficient than running a furnace, Some dealers just don't like them as they are more complex, some areas have such cheap gas heating costs that they are not worth it, and they do cost slightly more than AC alone. Also you state or utility energy programs may vary on rebates or electric rates depending on what you install.

You will like the humidity control with these systems.

And I have to get on my soapbox for a bit, and ask if you have changed out your lightbulbs to CFLs from incandesants. The CFLs use less energy, and put out less heat so that means you need less cooling. We changed ALL our lightbulbs, and got a new AC heatpump last May. Our June and July bills were HALF of the previous year!

I have had a decent BBQ but nothing like I'm used to. However, the seafood is out of this world! And I've never had better tacos. The taco trucks are in a class by themselves! That said, I can only dream about pizza as good as Minsky's on Mainstreet.

I just read a bit on heat pumps. It sounds fantastic except for the "back-up" you need in case of malfunction. Ummm, fireplace? That's our back up if the furnace goes, or hotel. Ground source sounds like the ideal, but I'm not sure that will be feasible on our lot.
The last two winters have been a bit cooler. There were several nights in the 30's with a few of those 32 or 31. Climate is wacky all over. Would we need a system in place to supplement a heat pump? I'm hot-blooded, but DH and children are sensitive to cold.

I worry that the heat pump won't be able to keep up with the summer heat/humidity here. This is based on nothing but ignorance on my part, however.

I would so jump on the CFL bandwagon if they didn't contain mercury, require specialized disposal (have a pile waiting for our recylcling program to figure out what to do with them) and emitted a decent colored light. I have some, but I'm not a fan. You would be happy that our kitchen and laundry is almost exclusively flourescent and those are the lights that are on most. If we ever remodel, I'm hoping LED has progressed enough to offer pretty lighting or something else has been discovered.

need to add, Tx electricity is crazy high. Using gas in the winter is more cost effective. Maybe that's why the furnace recommendation.

FWIW - led bulbs are fine but they are expensive. I pay about $20 a bulb and it costs about $60 for can lights. They are even more efficient than CFLs. With my $.10 a kwh, at 2 hours a day, it is about a 6 year payback for an average bulb. They truly should last (more reliably than a CFL) and so I've used them in hard to get to places. I was able to use them in pendant lights in the kitchen where CFLs would have been ugly (since you can see part of the bulb).

A heat pump works as an a/c as good as any a/c only system. I have no issues with cooling.

The backup is usually electric strips (in your climate) or can be a gas furnace. If you are talking power outage, no forced air system will work. The best system is hybrid where you have a gas furnace and a heat pump. Yes the cost is more but you have the best of both worlds. If you electric is high, then it is hard to justify even the extra small cost of a heat pump.

Now if you think the electric rate problem will get fixed or you get different rates with a heat pump, that might change the math. It is about $500-1000 to add a heat pump since it is just a reversing valve and some sensors.

David, yes LEDs are expensive. Quality of light is important to me, so I'd be willing pay for it. Since we're looking a long way down the road, prices may be more reasonable by then.

Thanks for your help Julie. We really like the second option best, too.