Well, the service guy was a little inaccurate in his assertions. R22 refrigerant will continue to be available but it will cost more and more to replace it. Look at insulating the house as best you can (particularly the attic) first and then when the AC finally gives up, replace it with a properly-sized system.

Thank you mike_home... I'm curious why you prefer bats?

Yes, right now, we are having extra heat. Not earth-shattering. It gets this hot every 5-10 years or so. The other night it was 100 at 11pm.

Beyond that, we were normally doing 78 during the day and 72 at night. When the AC could not cool down from the 78 before 1 or 2 in the morning, we changed the approach to try and keep it cooler during the day to have less to struggle with in the evening/at night.

Would it benefit us to have the re-ducting done sooner than replacing the HVAC system? (no the current ducts are probably not R-8... they have about an inch of mineral wool)

One more question... We have very little attic space (4-5 foot at the peak)... what is the best insulation (outside of foam) given the limited space?

I like the batt in that if you have 2 X 10 joists you can install a 9 inch batts. You can then put sheets of plywood on top if you want to use the attic for storage. You also know that the insulation will be uniform. The blown in is better if you have hard to access areas like your attic.

I think it is best the duct work and the equipment are nstalled at the same time. The duct work has to be sized to match the equipment size.

I'm a big fan of blown in cellulose. It performs better than fiberglass when there is a large temperature differential. You want to cover the tops of the ceiling joists a few inches to reduce the heat conducted by them (thermal bridging).

If your walls aren't insulated you need to do that also.

It doesn't sound like your unit is underperforming.

Your duct work needs to all be sealed and well insulated. Keep in mind that you probably can't do any work in the attic until things cool down.

15-20 years is a good life span for an AC. You can usually determine the age from the serial / model number. Take a photo of the plate on the unit outside.

The advise to get quotes later in the year is good. During a heat wave isn't a great idea.

I think when I retire from this field I am going to start selling Air Conditioning psychic readings but until that time comes.....

Seriously, I suspect your AC unit will live on until one really hot day.

Common responses: The AC can not be dead. No way, it was working 5 minutes ago...

Thanks for the laugh, but this is all too common. I could write a book.

If I told you that your AC will die in 7 days would you believe me and buy a new one today?

Austin Air Companie, I think if you had a reason why it was only going to live 7 days, I'd believe you. However, I can see what you say happening for many different things. This is an older house and I did say that when the plumber told us the sewer pipes were old. It wasn't until we were re-routing water and he brought up a sewer pipe and crushed it in his hand that I believed.

mike_home and jake: On the insulation, in the oldest part of the house, the ceiling joists are 2x4's - I kid you not. My husband poked his head up there late last night and measured. There is a quite a bit of blown-in but it has been trampled over time so I'm not sure of the effectiveness. Given that there is some blown in. Do you think that putting the batts cross-wise over the joists and leaving the blown-in would be best? How would we deal with the wires and ducts that are up there?

If blown in insulation is already present, then it would be best to add additional blown in on top. The joists can be easily covered with the blown insulation. You want to add at least 10 inches which would add a R30 - R37 value. This way you don't have to deal with disturbing wiring.

If the joists are 2 X 4 I would not risk walking on them to install batts.

I concur with the above. You can blow insulation without having to do nearly as much walking around.

Jake and others: We are doing a fair amount of remodeling and will likely continue for another 3-5 years. That means a fair amount of electrical work. The blown-in will be disturbed.

Austin Air Companie, I think if you had a reason why it was only going to live 7 days, I'd believe you.

The flux capacitor is running backwards requiring the compressor to need double the electricity and because it's been running this way for some time it has used up all it's muffler grease?!

How's that? testing, testing. LOL.

PS: if you're doing remodeling and such running wires and such thru attic it's best you do these things first then blow in insulation on top. If the boards going across a section of ceiling are 2x4 rafters I think I would look into a way of strengthening that to at least a 2x6 --- but preferably 2x8 minimum.

If you ever have trouble and need to access that attic again those 2x4's are easily forgettable and now a hidden danger to anyone who attempts to access this part of the attic. It could come back to bite you.

Mary, have you looked into local energy efficiency programs? With all the changes that you plan for the house, you should really have a list of priorities for improving the HVAC efficiency and comfort along with it. Typically, these programs paid for an energy rater to evaluate your home and identify the best place to put your money for the highest savings. Even if you had to pay an energy rater yourself, It might be worth it. Check BPI and Resnet.org. Efficiency programs are often administered by the local utility. Sometimes low interest loans are available that only have to be paid back at the same rate as the energy savings modeled for the home.