I’ve got HVAC folks coming to the house in five days to give me an estimate on replacing our current system (which is in working order now, but we estimate could be 15 years old at this point, so while we have the money, we’re doing it!)
Then I read in last month’s issue about HVAC systems and that SEVENTY FIVE PERCENT are installed incorrectly! I’ve pulled from that article several questions to ask each contractor, but it seems to me that I am doomed to have a system in place that doesn’t’ quite work at peak efficiency, no matter what I buy…
Asking for references is sometimes a moot point, because no one is going to give you a customer that is unhappy with the service or equipment. I’ve asked friends who they have and do they like them, which is how I weeded out some and got the ones that are coming. My mathematical skills are limited (but at least I can now balance my check book!) so figuring out any equations so that I know I’m getting the proper system is laughable… Do I just see if all four estimates recommend the same type of system?
Any advice that wasn’t in the article about how to go about making sure I get the right system and contractor? Not that it should matter, but I’m in Charleston, SC. (Heat and humidity are the name of the game right now!) I can give more specifics on our house and what problems we have now if you need them!
Replies
One easy thing I'd look out for is the HVAC contractor selling too much system. Easiest for you to check on the heating side. Whatever your current system is (in BTU/hour), you don't need any more than that (unless it ever didn't keep up). For that matter, if it was only running 50% of the time on the coldest day in memory, you could use a system that was 50-60% of the current one's size. That saves you installation money, floor space and ought to have better longevitiy and comfort(because it doesn't come on for such brief periods).
So one criteria would be to look for the contractor that takes some effort to determine the proper size of the system. Heat loss calcs or past performance of current unit, etc.
It is much easier for them to just spec a big unit. It is not their money, and they never get call-backs if the unit is too big (few people know enough to complain about that) - only if the units are too small. So they eyeball the house, round-up, round-up again and pick a large unit.
Are there specific concerns you have? A room that has always been too hot or too cold? Does the current system respond well to changing outside conditions? Look for a contractor who can LISTEN and respond to YOUR criteria with a plan of attack and some specific recommendations.
Thanks for the info. I have a brother named David Thomas!
Yes, of course we have peculiarities in the house. On one end, I have a room that doesn't ever seem to get heat in the winter. My husband has been up in the attic and thinks it has something to do with the ductwork, but we really have no clue what we are talking about.
We also have an addition built on to the house that is not on the central system - it has a "window" heating and air unit. That's important because it is not sealed off from the rest of the house. It was built onto the back of the house, so the old back door is now the doorway to the "playroom" and the kitchen window that used to look in the backyard is now open to the playroom.
The article in the magazine was quite helpful in regards to a system that is too big. I, too, subscribed to the thought that if this size would do it, then a bigger one must do it better! Hard to say that I was wrong!
Since I don't know much about these systems, will they see right through me when I start asking detailed questions?
you can have the perfect system installed, and still have problems. there are many variable that will effect the system. wrong, bad ducts, low insulations, black asphalt shingles, unit in attics, outside unit with no air flow. bad layout of house. I think what you are worry about has very little to do with performance. Its basically, you get what you pay for. most HVAC dealer are self employed, I would look for one thats been in local business forty years and have over twenty employees. These are the type that will be around awhile.
Edited 6/14/2004 2:37 pm ET by BROWNBAGG
I'm just an electrician but I have seen both the good and not so good installations and the results that flow from each. For what its worth I would concentrate first on getting the best energy analysis done by a relatively disinterested party.
IMHO, at least in this area of Florida, the best of these studies are done by the electrical utility. Typically for free or close to free. Alternately an independent analysts, ones not associated with a heating or AC contractor, can give a valuable second opinion. Seems to me that either or both might be worth the peace of mind. I would think a truly reputable AC contractor would have no problems with this.
I have seen that far too many of the contractors don't actually do any analysis. Had one contractor tell me that he had experience with the houses built in this subdivision and that because all of these houses were very much alike they all needed roughly the same system. Besides he told me systems don't come in small increments so something close was as good as anyone was going to get. I took this at face value. Sure.
I guess most times this wild guess, WAG, system works most of the time well enough. Sometimes not. When it fails it is an expensive error that many AC contractors are loath to admit or correct without legal action. Mostly the HOs just pay more for electricity and have less comfortable, sometime unhealthy, homes.
Worse one I saw was a case where the house had to be gutted and remodeled because the system failed to remove moisture. I was told that this was because the unit was grossly oversized. This built up to the point that the interior or the walls were wet. Rot, carpenter ants and mould took over. It was a toss up whether to remodel or start over.
Go to heatinghelp.com There are a bunch of smart folks who respond to Q from other professionals as well as homeowners. You may find one of them lives in your area and can come take a look, or recomend a good HVAC.
http://www.hvac-talk.com
Thanks - you've all been a great help. Of course, any other advice will still be greatly appreciated! I loved the idea of calling the electric company and have them give me their unbiased view. Will call them as soon as I finish typing this!
I don't remember if I mentioned that the electric utility terms this service as an 'energy audit' or similar. Sometime unless you use the right terms they don't know what your talking about. I did this once and got stonewalled until I used the term 'energy audit' suddenly the lady knew where to route my call to and it went down swimmingly.
Either way let us know how everything shakes out. Often I see questions asked but never hear how things went. I'm never sure if this is because they are too busy enjoying the results to post back or if the advice offered was so bad that the only contact they want is when their lawyer presents the papers announcing a law suit.
***** Update *****
Well, it's Monday and I met with the companies on Friday. Out of four, one didn't show. Go figure.
The three remaining companies... well, I figured that at least two would be similar in their suggestions. Nah. All 3 had something completely different to say about what I needed.
And the Manual J? Absolutely none took measurements so they could go back to their offices and input into the software. When I asked (and I did ask), one actually told me that only novices needed to use that. Completely contrary to the article and what I heard on this bulletin board.
As for what system I needed, I currently have a two and a half ton. Works just fine - although we have one room that doesn't heat well in the winter. I had suggestions for a 2 1/2 ton, a 3 ton and a 3 and 1/2 ton. I of course referred to the "Bigger isn't always better" rule of thumb garnered from the article. I swear, it's like they were looking at me thinking, "Silly girl, what are you talking about!"
I asked about adding our addition to the central air system, again got three different answers. One said no way, one said yes, but with a split system and one said no problem, we'll just use velocity to push the air across the room (this is also the one that said I needed a 3 1/2 ton system - to accommodate all the "velocity" that I'd be needing. And oh, by the way, since your furnace that is in good shape only has enough blowing capacity for a three ton, we need to replace that, too....)
Out of the three, there was one that was knowledgeable enough about what the folks in the house before us had done that did not meet code (and tell me, how did they do that?). He was also the one I felt was "most honest" in telling me that the furnace I had was in great shape, no need to replace it (circa 1995) but my AC outside needed replacing but he would just use what we currently have (2 1/2 ton). Of course, he is the one that said we could do our addition, using a split system. To me, that just sounds like a lot of money for not a lot of benefit, but we'll see when his estimate comes in....
Always interesting.....thanks for all your help!