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matt_t23

2 stage AC with Single Stage Variable Furnace

matt t
2 years ago
last modified: 2 years ago

I'm in the process of purchasing a new AC unit. I've been quoted for a 2 stage AC with a single stage VARIABLE speed furnace. Do these two systems work together or will I need a 2 stage furnace to support a 2 stage AC? House is 2 stories, 2300 sq feet, located 5 miles from the ocean (good breeze). AC and Heat are only used maybe 2 - 3 months a year total at max. Contimplating if I need two stage at all, given our usage.


Goodman model: GSXC16 and GMVS80


Thanks

Comments (21)

  • mike_home
    2 years ago

    It is possible that a single stage furnace has a blower which can be set to operate at low and high speeds when cooling. If you post the model numbers it may be possible to see if the furnace and AC condenser are compatible.

    matt t thanked mike_home
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    Your first answer confirmed that the extra run time on AC does provide some additional dehumidification but now you say it is a "gimmick" that I "fell for". Only with a 2 speed air conditioner. BUT it's still mostly a gimmick. WHY? a 2 speed air conditioner's first stage (most brands) is approximately 70% of capacity of the machine. It is more or less in dehumidification mode when the unit runs in 1st speed. (It must be a 2 speed AC condenser.) However, 1st speed turn on is not determined by humidity it is determined by temperature. Do you see the problem with that? The kick to 2nd stage is often times determined by time. Usually in the realm of 8 to 10 minutes or the temperature difference from set point to current temp of the structure (usually greater than 3 degree difference will initiate stage 2 within a few minutes). Humidity again plays no importance / no determination from ramp up or down --- it's all decided around temperature set points. How about now? Do you see a problem with that? So when in cooler seasonal temps --- the system will nearly always over cool... very much like a single stage air conditioner does all the time. PS: I'm not angry. But you should be for being 'duped', by the super slick advertising nonsense of the HVAC manufacturers. If I was angry why would I then turned around and explain things to you further so you understand the point being made here? What does 'SERVICE' mean to you? This is a service business, you will ALWAYS need service... better hope it's the kind you really want. I service the Katy, Texas area.
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  • matt t
    Original Author
    2 years ago

    Goodman model: GSXC16 and GMVS80

  • PRO
    Charles Ross Homes
    2 years ago

    Matt,

    What is being proposed is a system where the air conditioner's compressor is a 2-stage unit (has two potential operating outputs,) the burner for the furnace is single stage (has one operating output) and the air handler or air mover--which is common to both-- has a variable speed blower. It's probably fine except for the brand of equipment they're quoting--I consider Goodman to be at the bottom end of the HVAC spectrum, and in my opinion, so are most of the contractors who promote them.


    You're close enough to the ocean that you may wish to consider corrosion-resistant coatings to extend the life expectancy of your HVAC equipment.

    matt t thanked Charles Ross Homes
  • mike_home
    2 years ago

    I found the GMSV80 installation manual. The diagrams starting on page 17 show it can be connected to a 2-stage condenser. I tried looking on the AHRI Directory to see if the GSMV80 furnace and the GSX16 condenser are approved matches. They have changed the look up features again and I haven't been able to figure out how to find information.

    If you are near the shore and it is humid, then a 2-stage AC may be a could investment. If it is properly sized and installed it should provide better humidity control than a single stage equivalent. The furnace is rated at 80% efficiency. That should be sufficient if you have mild winters.

    matt t thanked mike_home
  • matt t
    Original Author
    2 years ago
    last modified: 2 years ago

    Thanks Mike and Charles Ross Homes - winters are pretty mild and we get a good breeze coming in from the coast most of the year. its been a very mild summer, but usually August / Sept and half of October are the most hot time of year with the house trapping heat. I only use the AC 2 months per yearin total and the heater maybe 3-4 weeks per year. It's very very minimal. After looking at the Goodman do you still think its not good quality? I know they had a bad rap in the past, but thought the newer units have fixed that... happy to get your expertise.

  • PRO
    Charles Ross Homes
    2 years ago

    @matt t,

    Turning around the reputation of a brand is a long-term effort. I don't install Goodman equipment so I can't speak to any quality improvements in the past few years. I do know a number of folks in my local area who installed Goodman equipment and experienced problems including my former next door neighbor. Some of their issues may be product related and some may be installation related (yes, most chose the low-bid contractor.) The better HVAC contractors in my area don't want to be associated with the Goodman brand.

  • sktn77a
    2 years ago

    Goodman HVAC equipment is as good as any other manufacturer's equipment at any given price point. The equipment you've been quoted is quite good. If it's installed properly, it'll be as good as any other manufacturer's products (at the same price point).

    matt t thanked sktn77a
  • PRO
    Austin Air Companie
    2 years ago

    Every manufacturer has it's strengths and weaknesses. The Goodman strength is typically better product warranties, lower part prices than leading manufactured brands once the unit exits it's warrantied life. (10 years)


    This particular Goodman model likely comes with life time warranty compressor as well as life time warranty heat exchanger. The con with this warranty is that these two parts rarely fail.


    Refrigerant leaks, which all manufacturer's suffer from can pretty much render any product warranty worthless. Not to mention refrigerant bans. (R410a is in the eyes of the global warming police, while this may take 20 years to work out it tells you that brand name means not as much as you think it does.)


    Trane isn't any better, it's well documented they've had problems recently with coils leaking freon just as much as Lennox as well as others including Carrier. A name doesn't do much in this regard. It isn't suggest any brand is worse than another... just don't put a brand on a pedestal because of the name on the side of the box. (You're more likely to be disappointed.)


    The name on the side of the box really doesn't matter that much. Nearly every manufacture in US brings parts from overseas and "assemble" the product here.


    Given your low use for your climate there's no reason to believe this Goodman equipment won't work well provided it's installed properly and maintained.


    There is no perfect HVAC brand, they all break. Typical life of an air conditioner is about 15 years.


    I service the Katy, Texas area.

    matt t thanked Austin Air Companie
  • PRO
    Charles Ross Homes
    2 years ago
    last modified: 2 years ago

    The name on the side of the box really doesn't matter that much. Nearly every manufacture (sic) in US brings parts from overseas and "assemble" (sic) the product here.

    @Austin Air Companie, you couldn't even get the English right in this post.

    Ours is an international economy. There are few products today which are completely manufactured in the U.S. Outsourcing to the most efficient material or labor source generally provides an economic benefit to consumers. You could base your opinions regarding the best quality HVAC system on the limited experience of a one-man (albeit larger-than-life HVAC guy and self-professed "HVAC whisperer") in the Katy, TX area or you could look to more objective, wider-range sources such as:

    https://www.hvac.com/air-conditioners/best/

    Spoiler alert: Goodman didn't even make the list of quality manufacturers.

    You might even take the advice of the following Consumer Reports article based on a survey of 24,000 CR members:

    In this survey, no brand earned a Poor reliability rating, but Coleman, Goodman, (emphasis added) Luxaire, and York received a subpar Fair rating. People should take this into account if they’re considering buying a central AC system from one of these brands. Source: https://www.consumerreports.org/central-air-conditioners/most-reliable-central-air-conditioning-systems/

    Caveat emptor.

    I don't service the Katy, TX area. Although I had my Volvo serviced there in 1981.

    Ray, I've never put much stock in your technical assessment, but it would appear that it is in stark contrast to objective sources reporting the quality of Goodman HVAC equipment. Houzzers will be well served to dive a little deeper than your posts to get objective assessments..

  • PRO
    Austin Air Companie
    2 years ago

    Mr. Charles Ross, I never put much stock in a home builder.


    So we can call ourselves even.


    Trane freon leak in video below from a different HVAC contractor... nothing new here. I bet I could find a leak video on any brand. Nature of the business.


    Now if you're the type of person who likes purple farts and unicorn confetti, you can buy into what CR is selling you. I believe there are people out there with my same views.





    It's more important that the equipment has the comfort features you want for your home. Nothing is immune to failure in this business.

  • PRO
    Charles Ross Homes
    2 years ago

    @Austin Air Companie,


    Trane freon leak in video below from a different HVAC contractor... nothing new here. I bet I could find a leak video on any brand. Nature of the business.


    First, the video you attached shows a unit with a refrigerant leak not a Freon leak. The nameplate on the air handler indicates it's configured for R-410a refrigerant. Freon is DuPont's registered trademark for R-22 refrigerant. It's different from R-410a. New equipment using Freon refrigerant hasn't been manufactured since 2010. You know that, right? The distinction is important, particularly on a website where homeowners are collecting information from "professionals." At least the narrator of the video referred to it as a refrigerant leak.


    Anything with moving parts can fail during its normal, useful life--whether its a top-rated brand or a bottom-of-the-quality-barrel brand. Suggesting all HVAC equipment is the same because they all contain foreign-made parts is like saying a Maserati and Kia are manufactured to the same quality level same because both have foreign-made parts. Many manufacturers outsource production of parts and subassemblies to manufacturers around the globe which deliver to their same quality standards as U.S. component manufacturers. Foreign vs. domestic sourced components is simply not relevant to a discussion about quality.


    When judging the quality of a particular brand of HVAC equipment, it's best to make assessments based on lots of data--not a single experience, and certainly not the experience of a single service contractor. To this end, houzzers will be well served to refer to Consumer Reports. 24,000 consumers is a pretty good statistical sample size for a survey about HVAC brands. To reiterate CR's assessment of Goodman equipment:


    In this survey, no brand earned a Poor reliability rating, but Coleman, Goodman, (emphasis added) Luxaire, and York received a subpar Fair rating. People should take this into account if they’re considering buying a central AC system from one of these brands. Source: https://www.consumerreports.org/central-air-conditioners/most-reliable-central-air-conditioning-systems/


    Sorry, Ray, but suggesting all HVAC manufacturers are in the same category because they use foreign parts is simply wrong. But don't take my word on that. Take it from Consumer Reports--they're in the quality assessment business. They put Goodman HVAC equipment in a particular category-- and if it isn't at the bottom of the barrel, it's close enough to think twice before buying anything with their label on it.

    matt t thanked Charles Ross Homes
  • sktn77a
    2 years ago
    last modified: 2 years ago

    I think consumer reports reliability ratings can be somewhat helpful when judging automobile reliability. There's no arguing that a Toyota is going to be more reliable than a Fiat. But. given that most homeowners wouldn't know how to rate an HVAC system if their life depended on it, their ratings for HVAC equipment must be taken with a grain of salt. There's a big difference between "the AC in my car isn't working" and "the AC in my home isn't working". Yes, they both have a condenser, an evaporator and a compressor, but the AC systems in cars are all pretty much the same while the AC system in residential homes are all pretty much different.

    I'm of the opinion that all generally available HVAC manufacturers products (at any given price point) are pretty much the same. You are not. So let's just leave it at that.

  • kevin9408
    2 years ago

    I need to agree with Ray here, nothing wrong with Goodman products. They sell a lot of HVAC equipment world wide, nearly twice Trane and four times Lennox based on annual revenue so it's obvious Goodman will have more complaints than others based on more units sold.

    Now if someone can find a comparison of comparable Total units sold by each company and the percentage which failed prematurely I'd like to see it as proof Goodman truly sucks.

  • Elmer J Fudd
    2 years ago
    last modified: 2 years ago

    "They sell a lot of HVAC equipment world wide, nearly twice Trane and four times Lennox based on annual revenue so it's obvious Goodman will have more complaints than others based on more units sold."

    I'm not sure where you get your revenue information, Goodman has been owned by Japanese Daikin for nearly 10 years.

    Let's assume your numbers are factual, let's move on. Your conclusion is not the only possibility. Here's another - Goodman prices are lower than industry averages for comparable equipment. Lower prices usually means higher volume if alternatives are more expensive. It also usually means lower quality, corners are cut to keep manufacturing costs low, that's what allows a lower selling price.

    Anyway, in and around the HVAC world, both pros and homeowners, Goodman is not a premium brand name, it's a low priced one. There's nothing startling about the Consumers Reports finding. Does everyone want, need, or able to afford a better quality choice? No. But price and quality are factors people weigh.

  • sktn77a
    2 years ago

    Daikin (Goodman) is the largest manufacturer of HVAC products in the world.

  • Elmer J Fudd
    2 years ago
    last modified: 2 years ago

    What does that change about Goodman? Since it's only North America where split, ducted HVAC residential systems are common, what percentage of Daikin's business does this represent?

    Having a large diverse parent says nothing about what may be a much smaller and regionalized business it owns.

    There was a time that General Motors was the largest car manufacturer in the world. A lot of its products were crap and products made by smaller (and often foreign) competitors were of higher quality and more advanced. GM's size did nothing to make its products better than others had. Same was true of Ford and Chysler. There's been a market for foreign cars in the US for many decades now. There's still very little foreign interest in US brands, aside from Tesla in recent years. No need to wonder why.

  • PRO
    Austin Air Companie
    2 years ago

    Does everyone want, need, or able to afford a better quality choice? No. But price and quality are factors people weigh.


    So you're going to take the word of a 3rd party magazine. There is quality and then there is "lip service". If something goes wrong with your plan you going to be able to sue CR? nope.


    I've been down this bumpy road before (first hand experience). I actually worked for an American Standard dealer earlier in my career. We sold it as a "better quality" product. Not only did I sell it, I also worked on an repaired these machines. My total career time is 27 years. If you're talking to a 20-30 something year old kid... well there's real fanboi's out there.


    So imagine me going to various homes that we sold American Standard units in. Trane / same difference. Telling people... so sorry I discovered a freon leak in the coil. (sure I could say refrigerant, I could say R410a... but saying freon is easier. KISS, everyone knows what freon is.)



    WHAT DO YOU MEAN I HAVE A FREON LEAK? your company said this was the BEST equipment? This unit is only 3 years old, 5 years old whatever doesn't matter. It's the same nausiating discussion over an over again.


    So do you want what you think is the best only to discover it's no better than anything else?


    Because no one here is saying that Goodman is the best. If there was a machine that was truly the best there would only be one manufacturer, and one brand. But instead there are 7 manufacturers and hundreds of different brands & models.


    It costs millions of dollars to make an air conditioner. It might cost $20 to rebadge a unit and turn it into a whole new brand. Wake up and smell the roses... you're getting sold.


    Buy it for what it does, not the name. Install it properly, maintain it properly. You will always need service after the fact. You're never done. That machine will break.

  • Elmer J Fudd
    2 years ago
    last modified: 2 years ago

    "So you're going to take the word of a 3rd party magazine"

    I don't take any one opinion as being the end of the story. It's a data point. Charles Ross Homes has shown to have balanced views, I appreciate his contributions and they're also additional data points on whatever the topic is.

    I have two other data points because as it happens, it was a question I posed to two different HVAC contractors who ultimately were chosen to do equipment replacement jobs for me a few years ago at two different locations, separated by several hundred miles but in the same state.

    Austin may remember my mentioning them, he was perplexed to hear of busy, highly rated contractors who both had backlogs of many weeks for equipment installation jobs. Both locally owned, with crews numbering in the 5-10 people range but so busy that they were booked out many weeks. One over a month. Both, coincidentally, focused on installing Bryant equipment.

    Because I'd previously heard Goodman scuttlebutt - here and on the HVAC talk board - I asked each in the context of talking equipment choices what they thought of Goodman products. It's been a few years but I think I can distill the comments accurately because both said about the same thing, which was - "We can install any brand you want but we don't recommend Goodman. Other brands offer better quality and value. Both we and Bryant stand behind their equipment, it's exactly the same as Carrier and we can sell it at a lower price". When there's a quality choice to make and the price difference is affordable, many buyers opt for the better quality. Nothing more is involved.

    I've heard about many brands of coils having problems over the years. Maybe Austin has some thoughts about why that is. It's hit many companies. Other leaks, whether coolant leaks or even air leaks from plenums and ducts, are often the result of shoddy installation work. And of course, all HVAC equipment ultimately dies. Customers paying for new equipment installs hope they've chosen the right contractor and properly sized equipment based on the specifics of their location and structure. And that a good job will be done so that the equipment will provide reliable service over its expected lifetime. It's not always the case.

  • sktn77a
    2 years ago
    last modified: 2 years ago

    "We can install any brand you want but we don't recommend Goodman"

    I think the only reason companies say this is because they can't compete price-wise with installers that do install Goodman. They install Trane, someone else installs American standard, someone else installs Carrier, someone else installs Bryant, someone else installs Lennox. See the trend? They all install different brands so consumers can't compare apples to apples. This is why HVAC installation and service prices are sky high.

    Look at the reference submitted by Charles Ross homes:

    https://www.hvac.com/air-conditioners/best/

    Number two was Amana (AKA Goodman)!

  • Elmer J Fudd
    2 years ago
    last modified: 2 years ago

    Like Yelp and other internet ratings, sktn, every type of ranking is influenced by attitudes and interests/intentions other than objectivity. All need to be taken with skepticism.

    As far as the practices of installers, each may be a bit different and it's probably hard to speculate.

    BMW dealers are not competing for the same customers with the same spending budgets as someone who wants to buy a basic KIA. They're competing with MB and Tesla and other upmarket brands. I suspect the same is true of those who specialize in HVAC brands the marketplace views as higher quality. There are also HVAC shops that compete solely on cost and not quality of labor or equipment, whether with Goodman or other lower quality brands.

    A Carrier/Bryant/Trane/ etc. shop is not competing with Goodman shops who position themselves to be low bidders, a lower price alternative, at least not in my area. Someone whose decision is to get the lowest possible price will do so, with other factors given a lower priority. Someone with this priority or constraint will find a lower bid, whether with a Goodman shop or others. When I was getting bids, an incredibly sleazy shop gave me 4 choices, the highest one (which was beyond unreasonable) included a "we're having a special program that will give you a $2000 "gift certificate" for a major cruise line" and the lowest one (at about half the cost of the highest alternative)was for unbranded equipment. Uh, no thanks. Don't call me, I'll call you.

    I know that HVAC contractors benefit from focusing their buying with one supplier so as to get better pricing and volume incentive discounts, that's true for all of them. And benefit from brand name recognition.

    Knowing that they're often tinged with subjective reasons, I still put great weight in the advice of experts. Especially those who need to stay plugged in and involved. If someone says "this equipment and our installation will serve your needs and I will be around for maintenance and warranty services should something go wrong. Possible but perhaps not likely", that's different than a hit and run opinion.

    I've always like the old saying about making buying decisions:

    Price- Quality- Immediacy of delivery or service

    You can make your decision by prioritizing one or two of these, you can't pick three.