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thglife50

HVAC Advice for a Newbie

thglife50
11 years ago

Thanks for reading my post and any advice that you may have. I have no knowledge about HVAC systems so both presentations sounded great to me. I was hoping someone could point me in the right direction.
I live in a 3 story townhouse in northern VA (20166). We run AC pretty aggressively from May until early October. Our current system is getting really expensive and it is on its last leg. We decided to get a few estimates.

Company 1: Option- 1 Gold SI / SV - American Standard Series System (13 seer) 2.5 ton
"Model#AUD060R9V3K 80% efficiency two-stage variable speed gas fired furnace
"Model#4A7A3030E 2.5 ton R-410 (Puron) environmentally friendly refrigerant,
13 SEER high efficiency air conditioning unit
"Model#4TXCB0036BC3HCA (Puron) cooling coil to replace existing
Install 1-ACONT602A 7 day Digital two-stage thermostat
** They did have a cheaper option but said we should get the 2 stage since our 3rd level gets unbearable

Company 2:Carrier Infinity 17 seer (3 ton)
model#: 24anb736 2 stage A/C with on demand Dehumidifier AFUE: 80 Input: 90,000
Model#: 58cva090-1-16 2 stage heat viriable speed blower
AprilAire 600 (something I can't make out) humidifier
Thisone has a 10 year parts warranty vs a 2 year with the American standard
Company 2 sized at a 3 ton because Carrier apparently doesn't make a 2.5 ton in the Infinity line
So my question is:
Is the second system worth an additional $3400, both in comfort and savings? I have very little knowledge about the 2 stage but it sounds impressive for constant room temps. The more expensive unit would have 3 years 0% financing while the first one would be paying cash without a loan. It would obviously free up finances for a few years even though it is more expensive.

Comments (27)

  • mike_home
    11 years ago

    Did any of these contractors do a load calculation? I am not familiar with the American Standard model numbers, but it looks like the furnace is 60,000 BTU while the Carrier is 90,000 BTU. One of these guys is wrong.

    The Carrier AC is a 2-stage unit and only is available in whole size tons. The American Standard is a single stage.

    The 2-stage AC will help lower humidity in the summer. It will not do much for the 3rd level temperature issue. Is this a finished loft with no attic above? You may need additional insulation and duct supply modifications.

    You are getting better equipment with the Carrier quote, and a humidifier. A difference of $3400 is big however.

    Does the Carrier quote include the Infinity thermostat and a 10 year labor warranty?

  • thglife50
    Original Author
    11 years ago

    Neither one did a load calc because they both said we have basic ducts, if that even makes sense. Like I said, I am clueless. The upgrade with furnace was because he said I wanted a 2stage for that as well. The Carrier does have a 10 year warranty and it would come with the wifi thermostat. I added that for an extra $100.

    It sounds like a great system but like you said, I am not sure which guy is right. I also don't know if I can recover any cost with resale down the road.

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  • weedmeister
    11 years ago

    I assume we're not talking Heat Pumps. Fine.

    Kick up the first quote to SEER 15 minimum.

    You need to see a ManualJ. duct work would be an issue after the fact, not before.

    You don't necessarily NEED two-stage AC. It's nice to have, but a variable blower gets you well on the way to humidity removal.

  • BobsHeating
    11 years ago

    How big is your home? One guy is quoting you a 4-ton furnace and a 3-ton AC (Carrier) and the other is quoting you a 3-ton furnace and 2.5 ton AC, thus the difference in blower size, and possibly in price. Also, the Carrier AC is a higher-end AC than the American Standard one. It has up to 18 Seer, versus 13 Seer on the AS one. It also has a two-stage compressor. The $3400 could be justifiable in the sense that the second quote is for larger, higher-end equipment.

    We sell Bryant (an affiliate with Carrier), so I am more familiar with the product than American Standard. It is a good quality product. It has a 10 year warranty on parts, but only if you register it within 90 days of installation, otherwise it reverts back to a five year. So make sure you get it registered if you go with Carrier. As for the warranty on the AS, most all of their furances come with a 10 year parts warranty as well, and at the very least, a 5 year. I've never heard of an AS being sold today with only a 2 year warranty. If that is indeed true, don't buy it. If a factory can't back it's product for a minimum of 5 years, you don't want it. Warranty is important, and should weigh in on your decision. Parts are becoming more and more expensive to repair.

    If you do go with Carrier, ask them what the price would be for a 2.5 ton, 13 Seer unit, like a 24AAB3. Then you can see how much that reduces the cost, just to make sure that both quotes are in line with each other. I do think you would enjoy the higher-end equipment though, especialy with how much with you be using it. It will keep the temperature steady, and it will be quieter. Plus, it uses less energy, so you could see a reduction in your utility costs.

    Good luck!

  • thglife50
    Original Author
    11 years ago

    Wow, you guys are awesome.

    My house is about 1650 sq ft. I am pretty sure the second guy is trying to sell me up because his lower end 13 seer 24ABB3 was going to run about 700 more than the american standard. I am assuming that would be with the same furnace.

    I can't figure out why neither company did a manuelJ test or a load calc. At least I don't think they did. There was some measuring, pictures, and a ton of questions. I don't think those are related to the tests that you have all mentioned. It seems to me like that should be something standard when giving estimates. If I call a 3rd company and request that test over the phone, will they oblige or just dust it off and do the same thing as the other two? I am very shocked because both companies are highly rated. But then again, I'm not sure that they are trying to rip me off. One is selling me a good reasoanble price unit while the other one has the "cadillac".

    I just hate to spend the extra money if it isn't going to be efficient because of my ducts. I sort of want to tell both companies about what the other recommended to see how they would justify theirs

  • thglife50
    Original Author
    11 years ago

    I have contacted another company to set up an estimate next week. Hopefully I can get a little more informed before I make a decision. I decided to go with Angie's List in the process. I had no idea that signing up for $25 will save me over $200 on my purchase with certain companies. Hopefully this next company will run the actual load test and give me the results. Either way, they are a Carrier company so I can see what they would do for the exact same system. I just wish that I fully understood this more so I made the best educated decision.

  • mike_home
    11 years ago

    "Neither one did a load calc because they both said we have basic ducts"

    This statement makes no sense. I would be leery of any contractor who said this.

    Most contractors don't want to spend the time to do a proper load calculation. They will use rules of thumb based on the area of the house. This usually leads to over sized equipment.

    The Carrier furnace is over sized in my opinion. You could move down to the 70,000 BTU size (58CVA70). It is not a big difference in price but it is important to get the proper size. I suggest you get a quote on a 95% efficiency furnace. It is going to be more money, but you will see a pay back if you plan to live in your house for several years. It may qualify for a local utility rebate.

  • thglife50
    Original Author
    11 years ago

    I was thinking about that comment after I typed it. It certainly seems like a lazy approach. I emailed the second company and asked why they didn't load test and he said that they have tested houses like mine many times in the past. I find that odd because he said the ducts were basic, whatever that means last night. Both companies get great reviews but now I am wondering if people do their homework or just listen to a great sales pitch.

    I will definitely ask the next companies about the 95%. I will also ask about a 15 seer price since some think that is my most efficient option for the price. Are there any other feelings about two stage units? I hear great things from people who have them but I don't know if it is worth the price. I do think I will stick with the humidifier option since I have two little ones in the house.

  • tigerdunes
    11 years ago

    Unless there are building or TH covenant restrictions, I would upgrade to the 60 KBTU two stage 95% eff var speed furnace, either AmStd or Carrier. If you are prevented from doing this, I would upgrade to the Heritage 15 heat pump model or similar Carrier model.

    I agree that the 90 K Carrier furnace quoted is too large.

    Don't like the AmStd thermostat quoted. You need a true two stage thermostat or else you will be on high stage all the time whether needed or not.

    For Carrier, you only want the Infinity controller.

    As far as the large price difference, the answer is no about the Carrier being worth it.

    I do recommend a whole house filter media cabinet if you don't already have one.

    Any hot/cold spots in townhouse? Now is time for dealer to make recommendations for improvement.

    IMO

  • mike_home
    11 years ago

    ".. asked why they didn't load test and he said that they have tested houses like mine many times in the past"

    That is a fair comment, but you need to call his bluff. Ask him to show you a load calculation of the other house, but with the correct geographic orientation of your house. This should be a simple edit to the input data , running the software program and printing out the results.

  • tigerdunes
    11 years ago

    What size and efficiency is existing furnace and condenser?

    Pst back.

    IMO

  • thglife50
    Original Author
    11 years ago

    It is an ancient builder grade 7-8 seer unit. Not sure how many btu

  • tigerdunes
    11 years ago

    life

    U should know the size and efficiency of existing furnace.

    U should know the size of existing AC condenser.

    Data plates should provide this info.

    To your knowledge, is there any reason that restricts having a high eff condensing furnace installed?

    Do you have a crawl space? Where is existing furnace currently located?

    Post back.

    IMO

  • thglife50
    Original Author
    11 years ago

    Input btu: 57,000
    Output btu, 46,000
    80 afue
    Outside unit is 2.5 ton
    7 seer
    We have an attic but no crawl space. The furnace is on the bottom floor. I have no reason to believe that we couldn't have a high efficient furnace but I also believe that the hvac companies would avoid telling me that so they can upsell.

  • thglife50
    Original Author
    11 years ago

    Input btu: 57,000
    Output btu, 46,000
    80 afue
    Outside unit is 2.5 ton
    7 seer
    We have an attic but no crawl space. The furnace is on the bottom floor. I have no reason to believe that we couldn't have a high efficient furnace but I also believe that the hvac companies would avoid telling me that so they can upsell.

  • tigerdunes
    11 years ago

    Condensing furnaces have to be able to vent waste gas. Usually this is done through an external wall. I would discuss this possibility with your dealer and get his thoughts. I really see nothing wrong though with the AS 80% eff furnace quoted. A very nice furnace. But as mentioned previously, you will need a true two stage thermostat that allows for best functionality of the furnace. Yes a bit more money but allows the furnace to operate on low stage when needed.

    If staying with 80% furnace, I would strongly recommend upgrading the condenser quoted to a heat pump model.

    IMO

  • thglife50
    Original Author
    11 years ago

    Thanks! I really appreciate your thoughts. I really don't mind paying the extra money if it is worth it. I wasn't sold on the 90,000 btu after I heard from a few people that it was quite large for my type of house. I am curious to see what the other two carrier dealers are going to quote now that I have a better understanding. I am assuming they will know what the whole house filter media cabinet is if I ask.

  • weedmeister
    11 years ago

    the media cabinet gives you room to use 4" filter media rather than 1". These filters cost more but last much longer.

    A ManualJ is not a load test, it is a calculation. One measures the rooms for cubic footage, type of wall insulation, number and type of windows, sun exposure, attic insulation and so on. The software then computes how many BTUs of heat and cooling are required to maintain the desired temperatures in the home for local high and low temperatures.

    It's good to ask to see this since they might not use the same desired temps as you would. Like 78 for summer and 65 for heating. For me, they also figured 89 as the maximum high outdoor temp. I had them use 96.

  • thglife50
    Original Author
    11 years ago

    Here is my latest. A man from a Carrier company came out and gave me the most complete education ever. He was an older man who has been in the business for a long time. He taught me about my ssytem and showed me a few tweeks that he would make in the ducts, without ripping out drywall. That was way beyond what the other 2 estimators have done for me.
    He showed me some calulations that led him to an initial system that would include:
    Infinity 58CVA070-16 80%/70,000btu 2 stage furnace
    24ANB736 (3 ton/16.7 seer) 2 speed AC
    Carrier coil
    WIFI controller Carrier
    Fixing the ductwork where it is exposed
    **He accidentaly quoted a 90,000btu unit and has to modify the estimate tomorrow morning. It will be intresting to see what the 20,000btu decrease does to the estimate.
    (That is what theother Carrier quoted w/o the humidifier for $1500 less)

    As add ons:
    Humidifier: $600
    Media style air cleaner: $495
    Water Heater: $1,095 (only because I asked)

    Most importantly: going to a hybrid heat pump 25HNB636 (3ton/16.5 seer) for $670. I would get an extra $100 rebate and the savings look like they could be huge. I figure they could be somewhere in the $500-$600 range annually.

    So my new question is do you think this system is a better option? I definitly feel more comfortable with these company. Which of the options would you choose if you went this route?

    I do have one last company coming out tomorrowbecause I had already scheduled them. They work with all of the brands of systems so I'm not sure what I will hear.

    This post was edited by thglife50 on Tue, Mar 19, 13 at 17:45

  • thglife50
    Original Author
    11 years ago

    I don't know if anyone will happen to read this in time. I had an interesting proposal for my final estimate. They had a cancellation on an install for tomorrow and are willing to put my system in just above cost, since they have to pay their installers anyway.

    He offered me two different systems, a baseline and a mid-line. He didn't think the infinity system would work well for me because he said a 3 ton unit would not work well in stage 1, which is essentially a 2 ton unit. Our 2.5 ton unit struggles as it is, so he had great concerns about the efficiency of a unit like that.That seems to make a lot of sense but I coud be wrong.

    His proposal was a Bryant "evolution", which he said was actually the same as the infintiy furnace. 80% efficient with 2 stage with a variable blower, 70,000btu The AC he quoted was a 16 seer high efficient unit. Not a 2 stage for the reasons above.
    This package comes in at $5,700 which is almost $2,000 less than the infinity. The catch is that I have to have it done tomorrow if I want that price.
    What do you think? The company is legit with amazing reviews. They are actually one of the higher priced companies so I was a bit shocked. He was too when I showed him my other estimates. I'm not so muched worried about the rushed decision. That actually fits my schedule. I want to know if his information is pretty solid.

  • mike_home
    11 years ago

    "He didn't think the infinity system would work well for me because he said a 3 ton unit would not work well in stage 1, which is essentially a 2 ton unit."

    This statement makes no sense. The low stage is used to maintain the temperature so the unit is not constantly short cycling. It also does a great job of lowering the humidity. It will allow you to raise the temperature a few degrees and still feel comfortable.

    What AC condenser, thermostat, and coil are included in this proposal?

  • thglife50
    Original Author
    11 years ago

    It sounded so exact when he was telling it to me. After I made the post I started to think about how ab2 stage would be an advantage. What I came up with (and I'm probably wrong) is that the lower stage runs at an efficient level to keep the room temp constant. The second stage would only be needed if it were really hot outside. That constant temp would also be what keeps the humidity down and results in the thermostat being able to be programmed a not higher. I'm guessing I'm on the right track.

    If that is the case, I would be better off paying the extra $1500 for the higher end unit and living with the extra comfort. Granted, I will end up spending more by going with the hybrid, humidifier, and cabin filter thing.

    Would you agree with that decision? I am surrounded by people who just tell me not to worry, I will figure the right thing out. I get no help outside of this forum.

  • thglife50
    Original Author
    11 years ago

    It sounded so exact when he was telling it to me. After I made the post I started to think about how ab2 stage would be an advantage. What I came up with (and I'm probably wrong) is that the lower stage runs at an efficient level to keep the room temp constant. The second stage would only be needed if it were really hot outside. That constant temp would also be what keeps the humidity down and results in the thermostat being able to be programmed a not higher. I'm guessing I'm on the right track.

    If that is the case, I would be better off paying the extra $1500 for the higher end unit and living with the extra comfort. Granted, I will end up spending more by going with the hybrid, humidifier, and cabin filter thing.

    Would you agree with that decision? I am surrounded by people who just tell me not to worry, I will figure the right thing out. I get no help outside of this forum.

  • mike_home
    11 years ago

    I have two Carrier Infinity furnaces and AC condensers in my 2 story house. The condensers are 2-stage units. The first floor condenser is 2 tons, the second floor is 3 tons. I have used them for 4 summers so far. I set the temperature at 78-79 degrees. I find this comfortable since the humidity is usually in the 35-40% range. They do an excellent job of humidity control. In the low stage the air flow is low and very quiet. There are no cold drafts coming from the vents. It is very comfortable.

    There is another reason why a 2-stage AC has an advantage over a single stage unit. Let's say your heat load calculation was 2.3 tons. If you got a single stage unit, the correct size would be 2.5 tons. But if you got a 2-stage unit, you would have to get 3 tons. This sounds wasteful since the low stage has a capacity of about 2 tons. When would the AC ever go to the second stage? Here are two scenarios.

    I set back my upper floor during the day to 82 degrees. On a typical day no one is on the upper floor, so there is no need to keep it cool. All the cool air remains on the first floor. At 7pm when the sun is going down, the thermostat calls for 79 degrees. The AC will go into the second stage to cool down the upper floor. It cools down fairly quickly since the sun is not beating down on the attic. The extra capacity helps in this situation.

    Let's say you have planned a big gathering at your house for a 4th of July celebration. It turns out it is one of the hottest days of the years. Your guests decide it is too hot to sit outside and decide to move into your house to escape the heat. You have a lot of people plus your are cooking some items indoors to keep everyone entertained. The heat load calculation the contractor did has no allowance for many hot sweaty people and your stove and oven on at the same time. Your heat load is now much higher than 2.3 tons. The AC is struggling to cool the house. The extra capacity of a 3 ton unit comes in handy in these types of situations.

    You have to decide whether spending the extra money is worth it. In my situation Carrier was offering a very attractive rebate for the 2-stage Infinity AC and furnace, plus I got an additional utility rebate for having a higher SEER rating. The final price after rebates was not much more than the single stage units. I am enjoying the added comfort and efficiency of the 2-stage units.

  • tigerdunes
    11 years ago

    Life

    I am always suspicious when I hear tactics like the Carrier dealer is placing forward.

    If you elect the Bryant system, you definitely want the matching and latest model Evolution controller. No substitute would be acceptable. I would also want the HP version of the AC model condenser quoted. You want the best matching Bryant evap coil, a third party evap coil not acceptable.

    Dealer is including new refrigerant lineset? It is needed to be the correct size.

    Did you even bother to check on the feasibility of a 95% eff furnace as I suggested in earlier post?

    Have you pulled the trigger yet?

    Post back.

    IMO

  • thglife50
    Original Author
    11 years ago

    Yes, his price for the 95% is actually more than the heat pump and 80 % right now because of a carrier rebate. The 95% and 3 ton 16 seer would cost more that is. That is the only reason I even considered the heat pump.je said that would provide better efficiency if I paired it with just an 80%. I would have to ask him for clarification if I am incorrect. I have heard so many scenarios at this point

  • thglife50
    Original Author
    11 years ago

    I am feeling pretty good about carrier infinity at this point. I can swing it into 24 months interest free. I have to decide if the whole cabin filter is worth $500. The humidifier seems like a no brainer.

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