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elmerjfudd

Not all HVAC pros have the same opinions

Elmer J Fudd
last year

A couple of HVAC pros discussing various functions and equipment operating modes. Both agree that the current Bosch line is an incomplete solution without integrating a communicating thermostat and fully modulating air handler. One of the pros observes that fully communicating and modulating equipment models are available from other manufacturers.




Comments (57)

  • PRO
    Charles Ross Homes
    last year
    last modified: last year

    Our resident HVAC "professional" is constantly reminding everyone that HVAC is his "day job." Sounds a little anti DIY to me. Oh, well, put me back in "builder box."

  • Elmer J Fudd
    Original Author
    last year

    If I understand, Cook's sentiment behind the "Anti DIY" moniker is this - these videos show you all the things I've learned to understand and do over many years. Don't fool yourself into thinking, Mr/Ms DIYer, that you can do what I can. You can't.

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  • kevin9408
    last year

    Mr/ms DiYer can do any thing they want and millions do everyday. If one has the intelligence greater than a cartoon character, inquisitive and motivated to learn the skill or knowledge of their chosen objective, they can do it.

    people with no confidence or common sense, low intelligence or motivation, Difficulty with learning or problem solving, or have a physical or mental health condition they still can learn to DIY but may take a little longer than the average person, but probably quicker than an obsessed cartoon character.

    Cook's sentiment is obviously self serving or narcissistic so any consensus here would reflect the same sentiment, or of one extremely gullible. You may agree but please don't degrade the ability of any person you know nothing about, or the deflection of your own deficiencies toward others as a valid basis to make such an assumption. If you think you're OK but everyone else isn't OK then there may be a problem, and could be a symptom of a pompous intellectual.

    Robert Bosch once said "I have always acted to the principle that I would rather lose money than trust" and I believe the same principle holds true today in Bosch. I've always trusted Bosch products for 40 years and see no reason to think otherwise of Bosch heat pumps. But the IDS inverter heat pump compressor isn't Bosch and a product of Mitsubishi. As I remember there is nothing but praise in the mini split community for Mitsubishi mini splits, so instead of reinventing a good product Bosch integrated the compressors into Bosch's own heat pump, and with some innovation made a better split system heat pump. Bosch has been doing this for 100 years and if I wasn't in such a cold climate I'd buy the IDS 2.0 with the indoor coil for $4480 (retail) without concern and install it myself. Ray hit the nail square on the head for Cooks motives and will leave it there.

    I would consider Elon Musk a DIY'er, as if he knew anything about transferring money online, building rocket engines or electric cars, but he can't do this with a lousy bachelor’s degrees in physics and economics. Many self taught DIY'ers have achieved unprecedented success doing things that according to the cartoon community they never should of done, so stop it Elon and call Rocket's R Us' you'll hurt someone.

    Robert Bosch also said "Never forget your humanity, and respect human dignity in your deals with others". Nothing to do with Bosch heat pumps and just liked the quote, and feel It's a hard thing to do by many including myself at times.


  • PRO
    Charles Ross Homes
    last year
    last modified: last year

    Really, Kevin?

    I think you're reading more into Ted Cook's commentary and that of others. By his own admission he's "just a mechanic."

  • G
    last year

    Not sure why this is turning into a DYI/anti-DYI thread now.



  • Elmer J Fudd
    Original Author
    last year
    last modified: last year

    One way to understand one definition of what a professional is, is that they are people who are so capable and skilled in a field of endeavor that their abilities are recognized by others and people are willing to pay them for their work.

    In contrast, many DIYers are stuck having to do things on their own, because whatever occupational activities they have don't provide them with enough income to hire professionals to do work quicker-better-safer-more correctly than they can do . Especially true for the skilled trades, like HVAC.

    If this is an evening for wise sayings, I have one with no attribution but it's a phenomenon I've experienced myself many times with company founders in Silicon Valley. Some very successful with names publicly known and some not and so anonymous. This tendency seems to run its way through the stereotype. The very smartest and most capable people in any field of endeavor are the ones who know their own limitations and who more quickly recognize what they don't know, than what they do know. Who know better than to pretend they know what they don't know. And who realize they will do better and achieve more by getting help from people whose knowledge and skills extend beyond their own in needed areas. Only fools think they know or can do tasks they're untrained and inexperienced with.

  • Elmer J Fudd
    Original Author
    last year

    "Not sure why this is turning into a DYI/anti-DYI thread now."

    It's just a conversation, it goes where it goes.

    I meant to mention earlier about the comment "Fully modulating systems are overpriced, and a typical homeowner will never ever see the ROI"

    Money spent on HVAC equipment purchase, repairs and replacement are costs of ownership, not investments. I don't see how it can be seen to be an investment. There is no ROI in a financial sense.

    For someone who wants to avoid spending money, don't buy any such equipment, don't repair or replace when needed, and keep what you have turned off. Still no ROI for that, just avoided spending.

  • G
    last year

    I'm sorry, but you are in error.


    HVAC equipment can be considered an investment for a home. A ROI w/ HVAC equipment is more or less 'energy savings' during heating/cooling loads. Supposedly, higher-end equipment (fully modulating, with VSAH, etc) saves more money on energy costs than non-higher-end equipment.


    The supposed money you would save on energy costs is.. a return on investment.. That's why there are piles of literature equating HVAC =/= ROI.


    I mean, go look at all the companies selling fully modulating systems and their supposed energy savings sell sheets.. 'up to x% in energy savings!'













  • Elmer J Fudd
    Original Author
    last year
    last modified: last year

    I'll let you explain, I think you're wrong.

    Your (heater, AC, it doesn't matter) is old and broken, can't be fixed and needs to be replaced. The cost will be $10,000. Tell me how to calculate what you think is the ROI for that expense. When will I have recovered the $10,000 and start to be money ahead? Please don't suggest that it will increase the value of your house - maybe that's the case in your area, it isn't in mine. When people buy a house, they want HVAC to work. Period. Bells and whistles are never touted nor paid attention to in my area.

    What companies use in their sales and marketing literature doesn't change anything. I've had car salesmen tell me a particular model is a good investment. Buying a car isn't an investment either unless buying one that will appreciate so that you can sell it for a profit.

    Where's the profit on buying or repairing HVAC equipment?

  • G
    last year

    Ok, your strawman arguments are becoming silly. And nowhere did I ever say HVAC equipment will increase the value of a home.


    Since you are having trouble reading, I will say this again:


    Fully modulating systems are overpriced, and a typical homeowner will never ever see the ROI for dropping $15k+ on them.


    If you are having trouble digesting that, here's some literature to read over;


    Air-Source Heat Pumps | Department of Energy


    'However, the energy savings can return the higher initial investment several times during the heat pump's life. A new central heat pump replacing a vintage unit will use much less energy, substantially reducing air-conditioning and heating costs.' [my emphasis in bold]










  • PRO
    Charles Ross Homes
    last year

    Unlike solar panels and windmills, HVAC systems don't offer a potential income stream to recoup their initial cost. They never "pay back" their initial cost.

    When we consider "return on investment" from HVAC equipment, we're referring to the return on an incremental investment. For example, if you are considering replacing your heat pump or air conditioner you might consider both a single-stage unit and a more efficient two-stage unit and maybe even a fancy variable-speed system as alternatives. We would look at the incremental savings derived from operating a more efficient unit and the incremental cost versus the base case. That would allow us to calculate a return on the incremental investment.

  • mike_home
    last year

    Fully modulating systems are overpriced...

    Have you ever in your own home replaced a single stage HVAC system with a fully modulating system? If so had did compare with your old system?

    Bosch units are decent, but anything without all that communicating garbage is a good fit for homeowners.

    Can you give an example of communication garbage? Did you have an experience where the communication link produced errors?

  • PRO
    Austin Air Companie
    last year

    Not surprisingly, Ray sought to minimize, if not dismiss Ted Cook's comments because he's a "Trane dealer." That's consistent with his efforts to put individuals in a box.


    You'd pick on him just as much as you do me. There isn't anything I could have said that would haven't been handed heat for whatever the run of the mill theme of the day is.


    Ted's opinion is going to be based around what he sells. Trane, Trane, Trane. So I was telling you the difference from him to me. Then you take this to mean I am bashing Trane? ha, ha, ha.


    Do I hate Trane? no. They break just as much or more than anything else. I used to work for a Trane dealer before I went off and started my own company 15 years ago. There's more to HVAC than trane, trane, trane. If you don't like my opinion now, one day soon you could. Does that mean another brand is better than Trane? no.


    Even when I said It's another choice. Pick one. ----- Let's not read that!


    Trane bashes themselves with broken Tranes, I work on them plus other brands. This mentality there is some flawless brand that never breaks. It hard to stop a Trane, slap a trane in there it will fix everything. You're free to think that if you want.


    I am a HVAC mechanic. I don't sell Trane, Trane, Trane. There in lies the rub.


    I don't always convince those who heavily persuaded thru gimmick based advertising... when telling them about "dealer" vs "non-dealer" situations. However, dealer heading is only about sales... to be a Trane dealer (or any dealer for that matter) requires annual sales. It could be 50K to 100K a year or more. This doesn't suggest that a company is good at repairing your broken in warranty system. (This isn't to suggest Ted is incapable of repair it is a generalized comment that Ted will probably not be coming to your home... he is one guy just like me that serves a certain area)


    So you choose a dealer to repair your trane, when the dealer is a dealer because they sell 10's of thousands a year to be that dealer. This doesn't suggest they are good at repair does it?


    Regardless of all of this --- what I've said in this post --- it's a choice. You pick. There are only roughly 7 or so manufacturers of HVAC equipment but hundreds of different choices from different brands to different models and different ways of doing things. I chose not to be all that tied to any one brand.


    If you're only about new equipment sales it doesn't take long for people to realize that. If all you want is new equipment sales and you're known as a dealer, that doesn't make you a repair specialist. Oh we'll just hire a tech for that. Then you're banking that you're going to find someone skilled enough that doesn't just go out and start their own company?


    How is it you think I woke up one day and I told myself the path forward was to start my own company? I imagine Ted Cook likely went thru the same thing I did in his early years.


    I have nothing against Ted Cook. I just chose a different path than Trane, Trane, Trane. Part of that reasoning was when the Climatuff was sent to Mexico. Now it's not even the climatuff anymore. (The compressor that made Trane famous.)


  • PRO
    Charles Ross Homes
    last year

    Ray,

    I'm not convinced you even listened to Ted's commentary. You slapped a "Trane" label on him and dismissed his comments the same way you seek to dismiss mine because you put a "builder" label on me. The problem in this instance is that Ted offered a favorable assessment of the Bosch variable speed system. Imagine that!

  • PRO
    Austin Air Companie
    last year
    last modified: last year

    I've watched his channel to know what he's about. Like I said before he is Anti DIY on you tube, he wouldn't fit in on this board either. I stated this from the get go... how would I know what his channel is if I didn't watch his content?

    He doesn't sell anything but Trane in new equipment. Watch my videos, watch his videos --- you will see a difference from brands in mine versus his. He only sells Trane.

    Brands I have sold over the past 15 years:

    Payne

    Comfort Star

    Maytag

    American Standard

    Goodman (single and 2 speed)

    GMC (goodman brand)

    Amana

    Grand Aire

    Comfort Maker

    Bosch Inverter


    If what you want is a Trane, then choose a Trane dealer. It's that simple. If you want to explore the world outside of Trane, find someone like me.


    Your Choice (the reader, not Charles)

  • PRO
    Austin Air Companie
    last year
    last modified: last year

    oh wow how could Ray have so much time to post on here putting in all these units that are inferior to the almighty Trane?

    He should be out running calls fixing all this inferior equipment he sells. He's only one guy, doesn't hire installers.

    Myths. ( I live in a hot climate where AC is used up to 9-10 months of the year most years)

    I am a HVAC mechanic first. That's how. If I am telling you to consider replacement it's for good reason(s).... of those reasons it's not because your system is or isn't a Trane. If you watch Ted's content for long you will get a feeling what he thinks about other brands besides Trane.


    I quit drinking the Trane holy water. Quite addictive though, I can tell you from experience.



    I still give you choices... none of them will be Trane. I have an American Standard system at my rental that was installed with not one, but 2 climatuff compressors in it. This was at a time when Trane and American Standard were really good equipment... before the sale to IR.

  • PRO
    Charles Ross Homes
    last year

    So you didn't watch the video Elmer posted, Ray. You apparently imagined what Ted would say based on other videos he's been in. But in this one he said something favorable about your favorite HVAC system. It's tough to make meaningful contributions to a discussion when you didn't watch the video that was posted. Instead we got your usual volume of unrelated fluff.

  • sktn77a
    last year

    "Supposedly, higher-end equipment (fully modulating, with VSAH, etc) saves more money on energy costs than non-higher-end equipment."

    Just to correct a common advertising misconception. SEER for SEER, multistage or modulating systems are no more efficient than single stage systems - you can't fool the first law of thermodynamics. They are quieter, and provide more comfort than single stage system, no argument.

  • Elmer J Fudd
    Original Author
    last year
    last modified: last year

    CR Homes comment that starts with "Unlike solar panels and windmills, HVAC systems don't offer a potential income stream to recoup their initial cost. They never "pay back" their initial cost.", is what I was trying to lead G to understand. Thanks CRH.


    Another point - for many people in many locations, it's considerably cheaper to heat homes with gas furnaces, so long as they're allowed. That's true in my area. It's hard to be enthusiastic about keeping the compressor running all winter with electricity at tiered pricing running up to 40 cents per kwh. Those of you in other parts of the US with cheaper power, your time is coming.

  • G
    last year

    I don't think you understand what I was trying to say. I'm glad you're not involved in HVAC engineering/design.



  • Elmer J Fudd
    Original Author
    last year

    If you're so involved, broadening your understanding will help you.

    People spend money on HVAC equipment and services to achieve indoor temperature comfort and features. As with all spending decisions, sometimes spending more gets you more, sometimes not. Some people, who can afford to, may choose to spend more money if they think doing so will bring them more comfort, convenience or features they wish to have.

    Buying HVAC equipment is no more an "investment" than is buying a Big Mac at McDonalds. People who seek strictly ROI should chop down trees on their own for wood to burn and put their money in the stock market.

  • mike_home
    last year

    Just to correct a common advertising misconception. SEER for SEER, multistage or modulating systems are no more efficient than single stage systems

    Multistage or modulating equipment can use less electrical energy to produce the same number of BTUs. However the efficiency gain will not be as much as the difference is SEER ratings suggest. The SEER binning temperatures were designed to make multistage equipment to look more efficient than they really are. This is why I advise people to compare the EER ratings. It is a simple calculation with one data point.

  • sktn77a
    last year
    last modified: last year

    "Multistage or modulating equipment can use less electrical energy to produce the same number of BTUs."

    Mike: I'd like to see some data supporting this. The only data I have seen over the years suggests this is not the case.

  • kevin9408
    last year

    "People who seek strictly ROI should chop down trees on their own for wood to burn and put their money in the stock market."

    This is a dangerous job and requires specialized expertise running a chain saw, and how to cut a tree to insure it falls the right way to avoid destroying a house, car or person. You MAY also cut your leg off.

    This is not a DIY job and should be left to a professional with a certificate of safety training and at least two years apprenticeship. If you try it yourself it's because you're to cheap or poor to pay a tree service the $1000's they charge, per Elmer's own admission.

  • mike_home
    last year

    I'd like to see some data supporting this.

    Properly sized and installed multi-stage equipment should run longer cycles compared to the same size single equivalent. The long runs are more efficient. I have not seen any data on this likely because it is small for most applications.

    The EER rating for multi-stage systems is higher than a single stage. However you could argue the higher efficiency is not due having more than one stage. You could be right. But the fact is manufacturers want to sell more profitable multi-stage equipment . Therefore you are forced buy a multistage system if you want better efficiency. I would also like to see data on this, but the industry has no interest in this. All AC and heat pump equipment is designed to generate a high SEER and SEER2 rating. This drives the behavior in the industry.

    As for gas furnaces I agree. Other than the small efficiency increase in long run times, a single stage furnace can be just as efficient as a multi-stage.

  • PRO
    Austin Air Companie
    last year

    So you didn't watch the video Elmer posted, Ray. You apparently imagined what Ted would say based on other videos he's been in.


    In one video I watched Ted admitted he has an 8th grade education. Now this isn't to put him down, these are the facts. Trane cool aid goes down easy.... just keep drinking it.


    He is a Trane guy as I said. He believes in Trane, built his business around Trane. If you use him that is what he will sell you. Trane. Nothing changes this. You can argue about watching a video or not... it doesn't matter. He's not going to recommend Bosch, he going to say whatever to sell what? Trane.


    Why does he have an opinion of Trane? It's what he sells. He has a motivation to do it. This doesn't make a different brand any thing less than Trane. They call this cool aid... just drink it. Open your eyes it's not that difficult.


    How much you Mr. Ross berate people who are lower than you... then you choose someone to illustrate a point....... ironic.


    Then you decide to put words in my mouth... never said I didn't watch it. You're tactical discourse as usual, Charles.


    Always wrong.

  • PRO
    Austin Air Companie
    last year

    Just to correct a common advertising misconception. SEER for SEER, multistage or modulating systems are no more efficient than single stage systems.


    It comes down to use + price you pay for electric. Here's an example for you...


    Saves me roughly 5000 KWH's a year. Multiply that figure by the rate you'll easily see how much I save year in and year out.






    If you don't do it, you're paying for it anyway by my numbers. It's not likely you pull this off with Trane because?





  • PRO
    Charles Ross Homes
    last year

    "It comes down to use + price you pay for electric."

    This may come as a newsflash, Ray, but thermodynamics doesn't care what you pay for electricity. It doesn't care that you service the Katy, TX area and it doesn't care how long you've been in business without understanding HVAC fundamentals.

    Now, back to the statement being debated:

    "Just to correct a common advertising misconception. SEER for SEER, multistage or modulating systems are no more efficient than single stage systems - you can't fool the first law of thermodynamics."

    I agree with the above statement with the caveat that SEER ratings can be misleading. The issue here is the limitations of SEER ratings for measuring efficiency. A single-stage 18 SEER unit from manufacturer A and and a single-stage 18 SEER unit from manufacturer B may perform exactly the same, and have the same SEER rating, which is calculated based on SEER test conditions of 80F d.b. and 67F w.b. indoor temperature and 82F outdoor temperature. That's a single point on a system's operating curve. While we can compare two different units at that single operating condition, the SEER rating tells us nothing about how they perform at higher and lower temperatures than the SEER test conditions. Even EPA mileage ratings are based on two points--highway and city driving. It would be more helpful to have a rating system based on performance over a range of normal operating conditions. I'm certainly not the first to advocate for that.

    Multi-stage and variable-speed systems are evaluated base using a bin temperature approach as Mike_home noted above. It's a different test methodology. I don't know whether it's fair to characterize the test methodology as skewed to favor variable-speed equipment, but it's worth noting that fully 2/3 of the operating conditions used to determine their SEER ratings are for outdoor conditions with lower temperatures than indoor conditions.

    The bottom line is that SEER ratings have limitations. Using SEER ratings to infer energy savings can give erroneous results compared with real world performance.




  • mike_home
    last year

    A single-stage 18 SEER unit from manufacturer A and and a single-stage 18 SEER unit from manufacturer B may perform exactly the same

    Is there any 18 SEER single stage AC system currently for sale? If so they are not very common.

    which is calculated based on SEER test conditions of 80F d.b. and 67F w.b. indoor temperature and 82F outdoor temperature.

    That is only one of 8 temperature bins. One of these days I am going to write a post explaining all the temperature bin testing.

    I don't know whether it's fair to characterize the test methodology as skewed to favor variable-speed equipment.

    I believe the testing methodology allows the manufacturer to pick what stage will be used for each testing bin. If I am correct then you know the staging will be set for the most favorable results.

    Savings based on relative SEER ratings is not accurate in my opinion. Yet this is how the decision to buy a HVAC equipment is done everyday. Results showing higher energy savings than predicted by SEER saving is very questionable.

  • Elmer J Fudd
    Original Author
    last year

    The conversation about whether SEER ratings are objective, useful, consistent, or otherwise could be had with EPA fuel mileage stickers on new cars. Or the Energy Guide labels on home appliances.

    I think most consumers ignore them.

    It's reasonable for the common good to have federal minimum efficiency standards that are regional - like SEER for AC and fuel efficiency standards for furnaces- but beyond that, I don't think they matter. For people living in areas where AC use is limited to the summer season, their vehicles' mpg performance can have a much greater personal budget cost consequence to them than the efficiency of their HVAC equipment. Does anyone pay attention to that? I don't think so.

    I don't think the methodology or flaws or inconsistencies in any of these required disclosed factors matter. Few care about them.

  • PRO
    Charles Ross Homes
    last year

    "Is there any 18 SEER single stage AC system currently for sale? If so they are not very common."

    This isn't a sales pitch for any type of equipment or any efficiency level. The point, and I think it's a simple one, is that at least for single-stage systems equal SEER ratings indicate equal performance--but that only reflects performance at the single test condition.


    "That is only one of 8 temperature bins. One of these days I am going to write a post explaining all the temperature bin testing."

    The SEER rating for single-stage systems is not evaluated according to the bin temperature approach. It is determined by a simplified calculation which reflects only a single test condition. Multi-stage and variable speed units are evaluated according to the bin temperature approach. That's part of the problem--two different methodologies used to produce a single performance metric.

  • mike_home
    last year

    The SEER rating for single-stage systems is not evaluated according to the bin temperature approach. It is determined by a simplified calculation which reflects only a single test condition.

    Are you sure about this? The way I read AHRI Standard 210/240 it seems the bin temperatures apply to single-stage, two-stage, and variable stage equipment. But if you have evidence of this then I would like to see it.

  • PRO
    Charles Ross Homes
    last year
    last modified: last year

    @mike_home,

    The SEER rating of single-stage (constant speed) equipment is not evaluated according to the bin temperature approach,. The SEER calculation was simplified some time ago. I've linked a good and very readable paper on SEER below. Here's an excerpt explaining the rationale:

    A key concept for SEER is the “bin” method. Temperature bins are just the frequency distribution of cooling hours for a season in a given location. For constant speed systems, the calculation procedures were simplified to eliminate the need to use temperature bin data. Instead the procedure simply uses performance data from the single outdoor temperature of 82ºF, which happens to be the load-weighted average of the temperature bin data (see the section below). The rating procedure still compensates for part-load degradation by assuming the air conditioner is sized to be 50% loaded at 82°F. The calculations for single-speed air conditioners become very simple:

    Equation 1. SEER = (1 – Cd*0.5)*EER82

    Source: https://www.aceee.org/files/proceedings/2006/data/papers/SS06_Panel1_Paper24.pdf

  • mike_home
    last year

    Charles,

    I looked through my files and found I have this article. Thanks for pointing this out. This further demonstrates the idea that SEER is measured under seasonal conditions is a myth. Most equipment combinations are not tested. The results are generated by simulations. I am confident the manufacturer will use the temperature bin method if produces better results.

  • PRO
    Austin Air Companie
    last year

    I believe SEER is more about giving the consumer some rationale to know they can expect in terms of what it will cost them to run the machine.


    It was never intended to be exact. Utility providers have what's called equal billing. I have one of those customers from years ago. It came time to replace their AC unit, I want to say 10 years ago or so. It took a few months to see the effects because it takes time for the equal billing to see that the decrease is not a glitch or some random event where the home owner went on an extended vacay.


    Because I have that customer on a service contract and go out there regularly I was informed the average billing dropped $170 a month. Like I said this was around 10 years ago. The machine I sold them wasn't even two speed. Just a run of the mill 14 SEER unit.


    So you understand the threshold... 14 SEER new, compared to what?


    If you look at any old piece of equipment they all say High SEER performance etc, etc. How high is high?


    SEER puts a number to it.


    Wait let's make it more complicated! ha, ha, ha.


    ------------ So maybe you consider 2 speed today --------------

    because of this added speed you say from 10 years ago -- this change out saved me 170 a month what would a 2 speed do?


    Hold the phone! There's a Bosch Inverter that may be so close in price to that 2 speed AC and it's payback is even better.


    You see SEER only tells "part" of the story. You first need to understand why, what, how SEER was intended. (Their is no guarantee your electric usage will go down --- there are provisions in the warranty docs that tell you that.)


    Wait let's hire a builder and home owner with too much time on their hands. Sure go ahead.


    You have to make a choice --- make it as complicated as you want. ( The AC inverter wasn't available 10 years ago, not even 4 years ago.)

  • PRO
    Charles Ross Homes
    last year

    Ray,

    The question raised by skta77a was an opportunity for you to contribute your technical knowledge to the discussion. Instead, you did what you routinely do: give a commercial for a Bosch inverter system. You presented a table of your electric charges by month comparing an 11-year old single-stage system with your new Bosch inverter system. You report the total kWh by month, but in lieu of temperature data by month, you report your own "Rayweather" assessment for an entire cooling season. That's right, an entire cooling season summarized in two words. Most HVAC "professionals" are familiar with the concept of cooling degree days; they are readily available online for Houston, TX. How about at least revising your table to include cooling degree days by month? It will still require houzzers to do their own analysis, but it's at least an improvement.

  • mike_home
    last year

    .... and home owner with too much time on their hands.

    Ray,

    Can you explain what you mean by this comment?

  • PRO
    Charles Ross Homes
    last year
    last modified: last year

    "( The AC inverter wasn't available 10 years ago, not even 4 years ago.)"

    Really? Oh, well, more misinformation to correct.

    The first AC inverter-driven air conditioners were available in the early 1980's. They were pioneered by Toshiba (which is now Toshiba Carrier.) Almost 11,000 units were manufactured for residential applications the very first year after it was introduced.

    "The inverter air conditioner, whose origin is Japan, is nowadays widely used throughout the world and is considered to have become the global standard of air conditioners. In 2018, countries and regions such as Japan, China, Europe, and Oceania saw a high inverter air conditioner ratio at 100%, 74%, 82%, and 100%, respectively. The inverter ratio in North America was notably low at 13%, because the inverter split air conditioning technology is relatively new in a long air conditioning history of North America; however, the inverter split air conditioner segment including residential ductless split air conditioners and variable refrigerant flow systems (VRF) has been recently growing faster than the entire heating, ventilation, and air-conditioning (HVAC) market in North America, and almost all U.S. based major HVAC manufacturers have added residential ductless split air conditioners and VRF to their product portfolio."

    Source: https://ethw.org/Milestones:Inverter-Driven_Air_Conditioner,_1980-1981#:~:text=Toshiba%20developed%20and%20mass%2Dproduced,in%201980%20and%201981%2C%20respectively.

    2022 -2018 = 4 years ago.

    There's a wide, wide world outside Katy, TX, Ray.

    I imagine you'll be sprinkling your usual lols and ha ha has or personal attacks on me in an attempt to camouflage your ignorance, Ray. Maybe you'll roll out the old staple of labeling this licensed professional engineer with 18 years of industrial and commercial HVAC and 23 years of residential HVAC experience as a "builder." Or maybe you'll throw in a red herring or do something to divert or deflect from the question.

  • Elmer J Fudd
    Original Author
    last year

    CR Homes, I don't know why you bother.

  • kevin9408
    last year
    last modified: last year

    Variable frequency driven motors have been used in HVACR along with many other countless industrial applications for many decades so it's nothing new. Some VFD controllers would cost more than an average car to soft start and vary the speed to ramp up to high speed of very large 3 phase A/C motors. The critical variable in any compressor pumping refrigerant was maintaining the refrigerant velocity high enough to bring back the oil to the compressor which wasn't collected in an oil separator. I'm not sure how this little inverter toy does it without the oil collecting throughout the entire system and washing out the bearings but it's above my pay grade.

    I've heard a Bosch Rep in a technical training video the company will be coming out with a new updated circuit/control board and thinks it will be called Bosch IDS 2.1 and could bring the fear Cook spoke of as a "force to be reckoned with" in the months ahead. This could address the communication issue the two techs were whining about.

    I've read the installation manual, and part way through a technical training video but must say this installation would qualify for a DIY job with just a basic understanding of air conditioning, a vacuum pump, B tank of nitrogen, gauges, and a set of torches with a DIY skill level of brazing. The manual was written in simple terms even a cartoon pig might understand, with step by step instructions to do every small task needed to insure success. So so simple

    like Goodman products available for sale to the JOHN DIY PUBLIC Bosch also allows their products to sold to the public. From one seller of Bosch IDS HVAC equipment there are over 5000 reviews with no 1 or 2 stars with the majority being 4 and 5. And it appears most are from those cheap and poor DIY'ers the OP holds such a high disdain for. This is what one of the no gooder said in a review:

    "It uses high and low-side line pressures, line temperatures, and ambient temperatures with an EXV to vary the speed of the compressor. This allows it to speed up and slow down according to evap requirements (37, 47deg temps depending on switch setting) and is independent of the air handler blower speeds. So it adjusts to demand! Heck, you can actually view line temps and pressures in the LCD diagnostic screen for a quick check of things without using a gauge set. There is no inrush, it's super quiet, and easy to set up. The build quality of these units are stellar, epoxy coated coils, beautiful bends, heat shrink on potential rub spots, and sheet metal is solid! Impressed!!!"

  • PRO
    Charles Ross Homes
    last year
    last modified: last year

    "CR Homes, I don't know why you bother."

    Houzzers should expect accurate information to be related by trade "professionals" in these forums. Unfortunately the "Pro" label on houzz doesn't guarantee that. Where misinformation is spread, it should be corrected by knowledgeable professionals so houzzers can make informed choices.

    What's ironic in this case, is that mini-splits-- which Ray abhors (whether ducted or ductless) are inverter driven heat pumps--- just like his favorite Bosch system. I don't think he's aware of that fact, though. And let's not tell him!

    Inverter-driven systems have been around for a while. I installed a number of Toshiba variable frequency drives in the early 1980s to control the speed of pumps, blowers, and processing equipment. They worked well, but the turndown was limited without adding constant speed fans to cool fan-cooled motors.

  • kevin9408
    last year

    Tim I frequent a lot of forums on different subjects and would NEVER ever take a comment by any member as fact and truth. Never! Houzz as a source of professional advice is a joke waiting for their IPO to hit the stock market at the right time. Keeping the Houzz user numbers up for show is the game, and after the IPO I believe there will be drastic changes coming.

  • PRO
    Charles Ross Homes
    last year

    @kevin9408,

    Could be. In the interim, some of us will do our best to provide sound, professional advice--not for personal profit nor inflating of egos but for the benefit of fellow houzzers.

  • PRO
    Austin Air Companie
    last year

    "( The AC inverter wasn't available 10 years ago, not even 4 years ago.)"

    Really? Oh, well, more misinformation to correct.


    ------------- I was referring to the Bosch Inverter coming to my market of Katy, Texas -------------


    If I can't get it, it's not available to my market. (I'm not going to sell vapor ware)



    Charles is a builder, 1 year and gone. I keep coming back long after your equipment is installed. Context as it were.


    For illustration purposes because Charles doesn't understand "context".



    I service the Katy, Texas area. (not a builder)

  • PRO
    Austin Air Companie
    last year

    What's ironic in this case, is that mini-splits-- which Ray abhors (whether ducted or ductless) are inverter driven heat pumps.


    mini splits were designed as a "spot cooling or heating appliance" without the need for duct work. This isn't about abhoring... it's about using the right tool for the right job.


    If you have a house that is 2000, 3000, 4000 sq. ft. --- you would need a house full of mini splits to condition those homes. Maintenance is often ignored until the machine is broken / not working.


    Maintaining and repairing a house full of mini splits? If Charles Ross sold you on that plan --- well it won't take long for that to get old, not to mention costly.

  • PRO
    Charles Ross Homes
    last year

    Ray,

    I think it may have come as a newsflash to you that Bosch didn't invent the inverter-driven heat pump. I get the impression that you don't know mini-split heat pumps can be either ducted or ductless systems (we've installed both types.) Mini split heat pumps aren't right for every application. As homes become better insulated and have less air infiltration heating and cooling loads are being reduced. That makes mini-splits increasingly more appropriate.

  • Elmer J Fudd
    Original Author
    last year

    I've stayed in a home a few times that has a ducted minisplit system. No wall, ceiling, or floor hardware is visible. It has multiple small air handlers and supply grills in each room that are small, round Unico-looking things in the ceiling. Two stacked side-discharge compressors outside, of the typical minisplit variety, it may be one for each of the two floors. I think the brand is Fujitsu or Toshiba. It's a 3 bedroom house, perhaps 2500 square feet. The system works very well, heating and cooling. Each room is a separate zone and of course the hardware is designed to ramp up and down to meet demand.


  • PRO
    Austin Air Companie
    last year

    Charles I think it may come as a news flash that I don't care what you think.


    If you think mini split is all that go ahead... it's more equipment, the more equipment, the more it will break, the more my job is secure. (I'm a HVAC repair man first, I offer more choices than just Bosch Inverter.)


    It's a choice. Do I care if the Bosch wasn't the first Inverter driven ducted machine? no. Does Bosch care? no.


    There are reasons above and beyond why I recommend or sell something. If you just want to buy something without any reasons why? I question that logic. Not to mention the mileage of that reasoning.


    I stayed some where with mini splits and it was fine. --- great air conditioning on average is a 15 year appliance. The more you use it, the more likely it will break, the more likely and more frequently it will need maintenance.


    Skip the maintenance, increase repairs.


    But someone has a different opinion because they sell something else. When I could have chosen the same or similar path they took, but I didn't? (there's reasons for everything)


    If you call a Trane guy he will sell you Trane possibly tell you all the bad things about other brands why Trane is so good. Lennox guy same thing. They are going to sell you Lennox, not Trane? No they are in bed with Lennox. But I thought Trane was better? I thought Bosch was better? (It's about equipment sales when you make foolish arguments like this)


    Carrier? If you call Carrier guy are they going to tell you to buy Bosch? No. How about Trane or Lennox? No. The argument you put here is about as well thought out as most of your arguments.


    I gonna go to a Ford dealership and see what they say about Chevrolet? I'm gonna go to McDonalds and see what they say about a flame broiled Whopper? Seriously?


    But the flame broiled Whopper in some parts of the country may be no more because?


    Let's fashion a new silly argument. --- sure provide me more material. No problemo.

  • PRO
    Charles Ross Homes
    last year

    The video at the start of this thread was a discussion between two HVAC pros--one of which you dismissed because he's a Trane dealer. Unfortunately, this same individual said flattering things about the Bosch which you would have known if you had watched the video. In between the video and this point in the thread you turned it into you oft-aired commercial for Bosch. It's not a one-size-fits all solution, Ray.

  • PRO
    Austin Air Companie
    last year

    He's never installed one Charles. He sells Trane.


    Commercial for Bosch?


    Charles loves circular logic... so Charles will nit pick about me talking about Bosch in a thread talking about Bosch vs other opinions... then the Trane guy says some flattering things about Bosch (a commercial for Bosch) -- In Charles mind this is ok?


    It's ok for the Trane dealer to say some flattering things about Bosch? But not me because I actually sell and install Bosch?


    Circular logic? (around in circles we go)


    This is a Bosch Commercial from me / From a Trane dealer who says some flattering things about Bosch in a thread talking about Bosch and Trane... a thread that was not started by me.


    You chose the topic, not me. Ha, ha, ha.