Ok, the only additional detail I could obtain was that the $1,000 option ("prewire + line set") includes the interior coil. Seems like this may be the way to go versus the piecemeal approach of $350 wiring + $300 line set + "$500-$600" coil = $1,250 (last two are per outside contractor)

Try posting over on the HVAC forum. http://ths.gardenweb.com/forums/hvac

You normally want all hvac equipment to match, and match should be in ARI directory. The high end condensers will never pay up. Ductwork should be design for load.

I don't know if I would part the equipment. But just so You know - lineset 3/8 5/8 x25 is only $80.

You're asking for trouble trying to do this later ad hoc. Unless you live an a cool climate where AC is optional, I would go with the builder on this one.

You need to develop a detailed specification (brands, model numbers, sizes etc) with your builder and the HVAC sub before you commit to anything , lest you end up with junk. The coil no the air handler needs to be matched to the condenser, you can't separate these items in modern systems. If they don't want to work with you leave it out for now, it's usually a pretty easy aftermarket installation. Have you spec'd the brand and model of furnace you're getting? If not you'd better think about it.

I haven't been able to obtain info (yet) on the condenser the builder would use, but in theory, if I did get the exact size/brand/etc, then we could install the condenser later and have all HVAC equipment match, no? (assuming builder handles wiring, coil, and line set)

Keep in mind that if you split the work between two providers if anything doesn't work it will always be the other guy's fault. Life is much simpler when you have one point of responsibility.

If it were me, if the builder will install acceptable equipment, I'd let him do it. If not I'd have someone else install everything later. For <$1K difference I''d let the builder's guy do it so you will presumably have the GC on your side if there are issues with the sub. There's no great reason the HVAC guy shouldn't be willing to give you Trane vs Goodman at an appropriate price differential.

A/C is no 'mix and match' Whatever brand you purchase, it should be installed by a certified dealer that will file the warranty with the factory.

It is absolutely foolish to do it 'later' or some of it 'later'. How can you afford to build a home, if you can't afford the A/C ? (this is assuming you need A/C in your climate).

Whether or not it is "foolish" to piecemeal the project is why I'm asking questions.

We've heard plenty of stories of folks who install it after the fact, once they have the cash to do so, (and often save a bundle) after all the more immediate cash needs are addressed (e.g. landscaping). It's only somewhat of a cost issue, because if we can get a better deal at a later date, then great. It's also a "don't want to finance it" issue. The cost goes up significantly when interest is tacked on. The house will also be significantly more energy efficient than our current house, so we have some questions as to just how unbearably hot it may (or may not) get. As you can see, it's not a total slam dunk either way. Hearing that the "prewire + line set" option done by the builder, and followed up with installation by a "certified dealer" (of course) of whatever appropriate condenser unit may be unwise is helpful. Why would the unit's warranty not be filed by the tradesman?

On a related note, just got word that the builder's chosen unit is a Rheem 13 SEER. I will go do my own research here shortly, but any thoughts on this brand etc would be appreciated.

You need to know the amperage of the condenser and the length of the run to determine the gauge of the wire. Same for the diameter of the liquid / suction copper for a particular A/C unit. Lastly, the evaporator will have to installed in the plenum, and you will need a drain for the condensate.

Sorry,

I did not meant to offend you. 13SEER is pretty much the bottom of the line (assuming this is "Rheem classic series"). Matching package barely dealer cost $2k total including the lineset.

My issue would be 13SEER (13.5) does not include two stage or ecm blower. For $5100 you should be able to nearly replace all provided equipment .

No offense taken, Brian S. Trying to educate myself. Some of the verbiage is way over my head, but for $5100 I just want to ensure it's a reasonable decision. We'll have forced air heat, so I'm not sure why the existing ductwork wouldn't be sufficient. Regardless, that will not be changed after the fact.

It sounds like the takeaway is either 1) Go whole hog and get it done for us for $5100 and end up with a relatively low end system- perhaps without a blower or 2) Have the builder do *nothing* and approach the problem after the fact, including getting it wired appropriately for whatever system is chosen. I.e. forego the builder's "prewire" option as well. And hope we come out equal to or less than $5100 and with relatively little headache.

I would cut out landscape before I would cut out HVAC...

X2 on nycefarm. and x3 x4 & x5.

builder doesn't do lineset. hvac company does
lineset. ahu, coil or furnace, coil depending on
what type system & all ductwork is done long
before condensing unit is placed. condenser
comes at end of build.

builder will accept low bid on hvac system. probably
has a hvac contractor he works with.
for something that effects the comfort of every day
live & the chance to get it right to start with...
take a set of plans & get several bids on your
own.
hire your own contractor, get load calcs,
duct sizing & design. pay the extra to not
have the lowest efficiency allowed by code
equipment.

low efficiency equipment will cost you extra
every month for each month you live in the home.

efficiency costs are upfront, but savings are
for the life of the upgrade.

ask lots of questions.

best of luck.

Great input, everyone. I've been back in contact with an outside HVAC contractor. He's been extremely helpful and not irritated at all with my questions. He mentioned sizing the unit based on our "Manual J" rating (an indicator to me that he knows his stuff, as I've seen quite a few HVAC threads where contractors refuse to do the calculation), also seconded the differences in line sets depending on unit chosen. Said Rheem is a quality brand, but he never recommends less than 16 SEER. He did recommend having the builder do the wiring for a cleaner job, so that's our final decision. We opted for the prewire only. We'll hire out everything else. Much thanks for all the feedback from more knowledgeable folks than me.

If HVAC could come before landscaping....it probably would! But we're obligated to get the backyard done in the first planting season, and we chose a LARGE lot, so $$$. Priorities, ya know. We're happy to swelter for a season if we're not breathing down our neighbors' necks.