New Heat Pump & ductwork, IAQ also
We recently had a home energy audit on our house, because our electric bills are astronomical.
Our house is 1847 sq ft, built in 1981. The attic HVAC equipment is original, and the ductwork is the "grayline" stuff (I think it's called) that we are currently discovering had some issues.
Our outside AC condenser is 2001 and either 10 seer or 12 seer (the two companies we've had look at our house didn't agree on the current rating.) It's not brand-matched to the attic stuff.
Anyway, there's no doubt that we want to replace our stuff, and that we can benefit from doing so. Both companies recommend a heat pump, and being in Texas, I think that makes sense, and does seem to be where the bulk of the electricity savings can be made.
Okay-- so I know prices are not to be included, and that's fine. I do have two quotes now, one from the auditing company's "sister" unit, and one from an independent HVAC-only company that I know some people have used and been happy with (including a local new-home-builder company).
The auditing company is recommending an entire package of improvements:
1) Blow extra insulation in the attic, seal penetrations, and install a "tent" over attic staircase hatchway, which is in our hallway.
2) Replace all ductwork with foilbacked ducts, reroute into straight runs, suspend so not resting on insulation, replace triangle boxes with metal Y junctions, replace return/supply silver cardboard looking boxes with metal boxes.
3) Install an Amana ASZ14 14-seer 4 ton heat pump with matching coils & handler in attic; variable speed fans, 10 yr parts & labor warranty, etc
4) They can add on a Lennox Hepa 60 system if we desire for extra filtration (we have allergies, asthma, and pets in the house, and who wouldn't want less dust, less pet odors in the air even if it does/does not remove all allergens?)
Now... the competing quote I have, which is only the HVAC side...
They work with Trane, so their stuff is:
1) A Trane xli14, xli16, or xli19 unit with a Trane Clean Effects filter system. Their guy said he spotted two sections of bad ductwork, and he would throw in replacing those two sections.
So, without quoting prices, let's just say I could have the Trane xli19 for a little less than having the audit company do all their work (not including the hepa filter, which tacks on an additional $3300 from the audit company, really making the prices vastly different); or the xli16 for a lot less.
Is there more savings to be had by going with higher SEER numbers, versus all that ductwork replacement?
I think I've seen that Amana is generally lower priced than Trane, so the fact that the auditing company is significantly higher, is that an indication that they are really marking their stuff up?
What is the opinion on Trane vs Amana?
Does the Trane Clean Effects solution compare to the Hepa60 solution, or is one clearly superior? Is there an ozone issue with the Trane filtration?
I just have no idea how to evaluate this... I don't mind paying more if it makes a difference in what I'm getting.. but I don't want to throw money away and not really get something for it.
Your help/input is greatly appreciated! Thanks!
Texas has some of the worst electric rates in the country.
Nat gas not available?
Crunch the numbers on the attached comparison fuel calculator.
The company installing the Amana, is doing a lot more work then the one doing Trane.
By changinf to Y's, they are lowering your air flow resistance, making the blowers work easier, so it doesn't use as much electric.
Adding insulation to the attic saves you money year round. The tent will stop/lower the infiltration rate from your attic. Saving you from having to pay to condition attic air.
If the Gray duct is flex,replace it all,it won't last much longer,well known issue.
Sounds like the audit company found undersized ducts,can't tell from here,but if so replace them,or rework them.
SEER means little in saving, if the duct system isn't right.
With extra insulation,etc.,and the chance to use R8 ducts,I'm surprised the audit company didn't find they could go to 3.5 tons.Did they do a Man. J load calculation??
If you are in a humid area,consider a two stage heat pump and cooling for lower indoor humidity,great comfort and a factor in allergies.
Our house is all-electric... Wish it was part gas!
Originally Posted by tigerdunes
Basics of heating/cooling. If you have air leaking out of your house, then for every single molecule of air that leaks out, a new molecule from outdoors must come into the home to replace it. So sealing the envelope is of high priority in energy savings. BUT, it must be sealed so as to not restrict fresh air exchange to an unhealthy level. You said you had an audit. Does that mean they did a blower door test on your home? If so, what was the leak rate? What is the equivalent length of a 1/2 inch crack? This is important stuff for you decision because it tells you whether the audit company is guessing on some issues or really knows their stuff. As beenthere said, replacing old flex duct, removing duct restrictions and eliminating air leaks into the attic mean a lot of energy savings. I'd carry it a little further and say that ALL the duct work should be sealed if it isn't already and that includes all ceiling boxes sealed to the sheetrock. Any recessed lights that are not air-tight models should be either replaced or made air tight with new trims, if possible, or attic boxes.
It is unfortunate that most HVAC companies are not more well versed in this important part of the industry. But leaky houses waste huge amounts of energy. The initial cost will likely pale against the savings over many years. The Trane products are good but no matter who's product or how good, none of them can overcome the air leak issues. So if the Trane contractor isn't going to address all the other issues, I'm afraid I'd have to vote for the audit company. JMO.
If YOU want change, YOU have to first change.
If you are waiting for the 'other guy' to change first, just remember, you're the 'other guy's' other guy. To continue to expect real change when you keep acting the same way as always, is folly. Won't happen. Real change will only happen when a majority of the people change the way they vote!
Replace all the gray flex. Find a contractor that will run round metal truck lines and then come off with flex.Amana is crap all it is a goodman. You will need every bit of that 10 year warranty plus the warranty is non transferable. so if you sell the house the warranty is voided. Trane is ok. Try to get a bid on a carrier infinity it is the best system out now.
The audit company did do a blower test for the house itself, and the ductwork also. The ACHnat rate was .60, he felt that an existing house best-case is probably .40, and a new house standard would be .35. We talked about caulking, sealing, weatherstripping... we have a BUNCH of windows, and two skylights - he was very concerned with how much the bathroom skylight leaked. They don't do that kind of work, but of course he pointed it out, that we should have it done.
Originally Posted by skippedover
If we went with a different HVAC company, we'd still have to address those issues, and I do agree that leaving a known duct grayline flex problem up in the attic seems very very very shortsighted.
Even if we did have a different HVAC company, after the replies here, I am more than ever certain all ductwork should be replaced. I'm sure blowing more insulation in the attic would never hurt! I just didn't want to pay an incredibly over-price when perhaps I could go with a couple different companies and end up with higher efficiency (for example 16 seer or even 19 seer), just as much done, and pay about the same but just involve a couple different suppliers. However, one thing the audit company does provide is come back and re-do the audit after their work, to show from a new blower test how successful the work was. So, I guess.. the question is the Trane that much better than Amana, or the 16/19 seer options that much better than the 14 seer?
I think someone else asked if they did a manual J calc, and I don't know the answer to that.. but he did say before they would install anything, they would have to do a room by room dimension to figure out something. The second HVAC company mentioned installing dampers in the ductwork to control airflow to some rooms that needed less, but other than that didn't mention anything about a room b y room survey.
I have one last company coming tomorrow at 2 that sells both Amana and Trane... but as of right now, I'm leaning towards the auditing company.. however, it's going to be over $16,000 and I just want to cross my t's and dot my i's before I commit that much to an 1874 sq foot house that could possibly require much less money to put into the same type of shape!
I recently had a similar system installed. I went with the ASZ16 (2 stage).
My contractor installed the Lennox HC16 - it's a MERV 16 media filter (4-5" thick). The particule capture rate is very good, not quite HEPA, but closer than almost anything else. And, most HEPA systems are bypass (they don't filter all of the air, just a portion). I'm not familiar with their HEPA system, but the HC16 should only run you a few Ben Franklins.
If you are comfortable working in your attic, you can do the sealing stuff and blowing yourself. But it takes a lot of time.
Best of luck.