The 15 year warranty is likely a third party warranty. Could be AIG, underwriting the warranty. The problem with these is that because it's a 3rd party those last 5 years beyond 10 everything comes thru the 3rd party. There are likely limitations to it beyond just keeping the unit maintained annual with proveable records.

The refrigerant is probably the biggest sticker because the manufacturer nor the 3rd party warranty provider is likely going to cover that. Especially once the phase out begins possibly as early as 2024. This only effects you if a refrigerant repair becomes necessary.

Equipment changes / refrigerant phase outs etc in 10 years from now is likely to be a whirlwind when it comes to HVAC. At the 15 year mark? I wouldn't count on a warranty like that for much.

Say the annual maintenance contract is $150 which may be low for your area. x 15 = $2250

Not saying annual maintenance is bad or shouldn't be done, but you need to consider all costs for what you're going to do. You skip the maintenance 1 time the underwriter of that contract has every right to turn that contract into a worthless piece of paper.

If your contractor turns out to be poor service wise, that warranty contract is tied to them. Again this is not saying it will or won't turn sour. I've been doing this for a long time so I am looking 5 miles down the road how these things go bad all the time in my experience.

This isn't to suggest I am perfect / never have any customer problems / difference of opinion etc. I've had these 3rd party warranty contracts before and they can be a pita on my end as well as the consumer end.

I've found it's better to not chase contracts in which some other entity is deciding what my time is worth / nickel and diming me and my time which in turn degrades the customer experience.

Little things like timeliness of service. It won't take you long to see how worthless that contract is if you start having problems and if you have to spend $2250 just for maintenance to keep the contract enforced over 15 year term?

If you decide to go that route you should be fully aware & read that contract.

In terms of Trane vs Lennox they are probably more equal than you realize. There is no perfect brand they have strengths and weaknesses. Pick the contractor you will think will provide you the best service. You're in a hot market -- so service is key unless you like sweating unnecessarily.

Ironically enough the warranty contract doesn't cover work outside of normal business hours. Those hours are decided by the warranty company providing the coverage as well as the contractor. Keep that in mind.

I normally would discourage signing up to an annual maintenance in order to keep an ongoing warranty. However what is being proposed here is interesting. The Phoenix area is hotter than Katy Texas. This means the AC is running 10 months or more a year and you like it on the cool side. How many AC units installed today will make it to 15 years without any repairs? It becomes playing a game of odds, but the game has to be fair to you.

First thing is to find out who will do the warranty work. If it is a third party as Ray suggests then that is a big negative. Ask how much annual maintenance will cost and what services will be done. You should also ask if loss of refrigerant is covered. Most likely it is not, but that will become an expensive item in the future. Also ask if there are any service charges or any out of pocket costs in the event of a repair.

The typical warranty is one year of labor and parts are covered by the manufacturer for 10-12 years. A 15 year labor and parts warranty is almost too good to be true. Read the fine print carefully before signing.

First thing is to find out who will do the warranty work. If it is a third party as Ray suggests then that is a big negative.

The installing contractor will be the only one listed on the warranty in question. I believe AIG had a thing in there years ago where you could pay a fee to switch to a new contractor, but that wouldn't be a game you would win in my opinion.

The underwriter of the warranty may not be AIG. I suggested AIG is because they are one of the biggest in USA.

Contractors typically use these sorts of contracts to lock you into only using them. If service is good / timely etc. then all's good.

In my experience that is rarely the case... even without such contracts.

The story usually goes like this: I had a friend or a friend of friend install xyz. The unit does this or that they tried to fix it. It still does this or that (what it does doesn't matter only that it doesn't work right in the eyes of who is operating the machine)

It could be noise, it could be cooling performance it could be? fill in the blank.

Air conditioning is more than just turning on and off in a hot climate. That system will be put thru the wringer.

It's not a good idea to change contractors. Conflict of interest.

I am always looking for new customers, but free from a conflicted mess. This is why it's important you pick the contractor you like. Avoid the gimmicks.

If you still don't understand let me know why I will attempt to clarify further if I can.

@Austin Air Companie @mike_home thank you both! So I spoke to my number one choice and it is a 3rd party warrenty that covers me even if they go out of business. I did confirm that refrigerant is included as well as the company I purchased from would be the ones who come out and work on it. They did mention the system needs to be serviced once a year which is fine with me. So currently I am looking at the trane xv18 variable speed unit at the same price others quoted me for a single stage unit with a 10 year warrenty. They also mentioned they would put in a 4 ton and adjust the system to only use 3 tons and if I need to increase it later I can.

I don't think they can do that because typically the 5 ton can drop down to 4 ton. not 4 ton to 3 ton. Sounds like a salesman who doesn't know logistics of what can or can't be done.

He's doing everything he can to make the sale. Because? this is how he gets paid.

The 3 ton can drop down to 2 ton.

I would also wouldn't consider what someone tells you as truth. You need to read the contract because that is what will prevail. Hearsay doesn't mean anything.

It's one thing to say refrigerant is covered when it may cost $400 or so a drum. But with phase outs right at the door. The drums could jump to over $1000 or more over night.

California has rules that ban R410a refrigerant sales as early as January 1, 2025.

Trane warranty documents specifically say refrigerant is not covered. If a company goes bankrupt you think another company is going to want to get involved in that folly?

Insurance companies are known widely as deniers when it comes to paying claims.

Don't take someone's word for it. Read the contract. The whole contract.

The biggest problem with major manufactures implementation of the inverter AC realm of equipment is that these are all 'communicating' systems.

They require proprietary controls to operate the system. If that communication link is broken anywhere that system will not work. Trane, American Standard, Lennox, Ruud, Rheem, Carrier, Bryant they essentially all implement Inverter systems the same way with proprietary controls.

Amana, Daikin & Goodman moved this hardware to the furnace section. So the con here is you will always need that particular furnace to supply the signal to make the AC inverter condenser to run. For my climate it's more likely for that furnace to out live the AC part anyway.

Bosch does this entirely different as everything is done from the outside condenser main board. It doesn't rely on any communication from the indoor equipment like the aforementioned brands.

There is a new comer the Lynx system Ducane & Concord which is an off shoot brand(s) from Allied and off shoot of Lennox. So the Bosch may have some competition soon... just not yet in all areas.

There are other advantages to Bosch because of the way in which they do things. There are cons as well but I think they put you in a much better position to win meaning it actually pays you to use it. The comfort it gives is gravy.

You're not likely to get there with a 'communicating' type system. There are nearly always dumb problems to work out.

Extended Warranty don't / won't cover all costs to repair.... Straight from Trane website.

(Read the contract)

Click to enlarge.

It's amazing how the OP's original two questions: Lennox vs. Trane and 3-ton vs. 3.5-ton capacity could end up as a commercial plug for a Bosch system with a note or two about R-410a sprinkled in.

What a long, strange trip it's been....

Charles they call it information.

Someone is trying to make a choice the choices aren't limited are they? They call that freedom, btw.

You can't choose something you don't know exists?

Charles & Fine dining... you sit down, they give you a menu?

Ray,

The OP has been comfortable and their utility bills reasonable with a 3-ton single-stage A/C over its 15-year service life. There shouldn't be a debate about the required capacity nor the fact that a simple single-stage unit is appropriate for the application.

You might have even stated a good rationale for keeping the investment in a replacement system low if you're concerned about the future availability and cost of R-410a. A lost opportunity.

They also mentioned they would put in a 4 ton and adjust the system to only use 3 tons and if I need to increase it later I can.

Hector,

Can you post the model numbers of the air handler, condenser, and coil? This will help determine if what the HVAC installer is proposing is even possible.

You might have even stated a good rationale for keeping the investment in a replacement system low if you're concerned about the future availability and cost of R-410a.

The idea behind spending slightly more money for an AC inverter, is that the system will recoup the money you spend on it via reduced utility bills. But this *situation* is far less likely if you go to major manufacturing brands that require expensive controls required to make their form of inverter run. ( I did warn about that didn't I? )

When you're in a hot climate there are different attributes to consider. 9-10 months of use vs a 2 or 3 month climate?

Utility rates for my area are up any where from 14 to 17 cents per KWH or more. So one can easily make up the difference in cost from a run of the mill AC as equipment prices are all up on that end as well. A low end 14 SEER entry AC will burn 50% more energy than an AC inverter. Given the use spectrum of a hot climate you'll easily recoup it. (the difference, not the total amount)

It's still a choice and you're going to choose something in a hot climate. If an entry level machine goes down 10 years from now, you're likely going to buy another new machine because of cost to repair it.

The inverter AC would be worth more, thus better to repair it vs replace. Many reasons why replacement comes up is that the equipment in question "isn't worth repairing".

If the experience level of who you are using always works on new equipment? They're in it to sell you new equipment. So plenty of ways to look at this.

It's still a choice. I'm just providing info and possibilities. Pick whatever you want, I am not moving in with you.

I service the Katy, Texas area.

@mike_home it is a trane xv18 unit. I believe here are the model numbers for gas and ac.

m#4ttV8048A1
m#tud2c080acv4
m#4txcc009ds3

It also comes with communicating technology.

@austin air - so it looks like I was able to negotiate the variable unit at a cheaper price then others were offering for a single stage so I decided to go for the variable unit 4 ton.

@charles Ross homes - thank you so much for the information and thr contribution to this forum. :)

@austin air - so it looks like I was able to negotiate the variable unit at a cheaper price then others were offering for a single stage so I decided to go for the variable unit 4 ton.

Nothing wrong with that as long as installation is proper and install company stands behind their work. I just feel there are better ways than baptized in Trane holy water. I don't mind working on Trane units once that warranty period runs out. ;-)

The communication part of it can be good as well as a nighmarish error code hell. Let us know how it goes. I am always up for a good or bad HVAC story no matter what brand it is.

I did a search on the AHRI directory and I believe the certificate number for your system is 207474491. Here is an image of the certificate:

Overall this is very nice equipment. However be aware the AC can produce up to 4 tons of cooling. Your duct work may have been designed to only handle 3 tons. You stated in an earlier post the installer can limit the AC to 3 tons of cooling. I am skeptical if that can be done, but I am not a expert Trane equipment installer. Ask the installer to explain this to you.

The SEER rating is 18.0, However the more important rating to consider in Phoenix is the EER rating. Your system has an EER of 12.5. EER is measured with an outdoor temperature of 95F degrees. That is a condition that happens often in the Phoenix area. The variable speed AC systems have great SEER ratings, but not so good EER ratings. This means the energy savings will not be a high as the SEER rating suggests. It will be interesting to see how much money you save on cooling costs compared to your old equipment.

The 2-stage furnace is a rated for 80K BTU at 80% efficiency. That means the output is about 64K BTU. Most likely it is oversized for your Phoenix home. I would expect it will always operate on the low stage expect in rare cases when you do a large set back on the coldest day of the year.

Good luck with your new equipment and keep us posted on the installation.

The joys of a hot climate.... my own KWH's use compared to 14 SEER over the past several years. This will show you how this can pay you back. The higher the rate goes the easier and quicker the payback.

So you can see how this Bosch Inverter can pay for itself (in a high use climate or very expensive utility rate over 23 cent per kwh)

The higher the rate, the easier the payback. The longer the cooling cycle the more likely as well.

click to enlarge.

notice the comparison when rates were only 10 cent per kwh, compared to now 15.5 cent to 17 cents?

It all adds up. If you don't do it, you are buying it anyway just not getting it.

Obviously if you aren't staying put selling the house or live in a light use low electric cost? So it's not for everyone in that regard.

I'm just providing numbers that prove what I am telling you over and over and over. In some circles they call this facts. Not financial advice, but the choice you make is a financial one.

You're gonna pay someone and from my numbers you're paying for it no matter if you do the inverter AC or not. Record heat in the chart stands for more days over 100F than what occurs in a typical year with little to no rain. How I run the machine hasn't changed, only the weather outside changes things.

Let the disagreements fly... ha, ha. Cooling envy.

Ray,

Did you calculate the number KWH used for heating or cooling only in each of the years? That would be a better comparison of the relative energy use. Do you have the data for 2017 and 2019?

Ray,

Did you calculate the number KWH used for heating or cooling only in each of the years? That would be a better comparison of the relative energy use. Do you have the data for 2017 and 2019?

Yes but heating season here (Katy, Texas about 3 clicks west of the Gates of Hell) is bupkiss for the most part when it comes to heating costs. Nothing consistent. Some years there is really no heating season here at all other than a few days here to a week or two there.

It's very mild in winter here. Normal highs are at least in the 50's Often times we are sporadically still running the AC in Dec and January. We can get cold / chilly on occasion, but that is not the norm for long.

In 2017 I was paying 8.8 to 9 cents per kwh for electric.

Usuage was pretty similiar to 2018...

March 500 kwh

April 699 kwh

May 1021 kwh

June 1447 kwh

July 1655 kwh

Aug 1722 kwh

Sept 1277 kwh

Oct 849 kwh

Nov 634 kwh

total 9804 (10948 2018)

Difference 1144.

Weather in 2017? we had the hurricane here that year. (Harvey)

2016? we had tax day flood? So alot of rain those years.

Any time there is alot of rain it cools things off so usage isn't what it typically is.

I chose the best years to illustrate it. I moved to this house in late 2016. 2019 -- I installed the inverter AC late that year. So that presents more confusion than anything else.

***So it is important to note the records I show is all Air Conditioning usage. No heating.

Humidity here is a round the clock ordeal. In the off season it's not uncommon for me to lower than typical summer set points to run the system to rid the humidity. (stale air, what ever you want to call it)

Usually 70F is about as low as I go to do that. The inverter AC does this much better than single or two speed. More to it than just money savings off the electric bill.

In order to calculate the savings on cooling and heating, you need the calculate how electricity or fuel was used in each year. I understand it is more difficult to do this in Katy Texas. So let's use the numbers you provided to calculate the savings.

You replaced your 4 ton 14 SEER AC with a Bosch 18 SEER model. The calculation for energy savings base on SEER ratings would be:

1 - 14 / 18 = 22.%

If we average the 2017 (9,804) and 2018 (10,948) electricity usage amounts we get 10,376.

The average of the two normal years of 2020 (5,772) and 2021 (5,574) is 5,673

The calculation of the average savings between 2017/2018 and 2020/2021 is:

(10,376 - 5,673) / 10,376 = 45%

Can you explain how the energy savings is more than double that which is predicted by the comparing the 14 and 18 SEER ratings?

@mike_home,

There are a number of problems with the performance data Ray presented which disqualifies them as an objective and accurate comparison. For starters, he apparently doesn't know the difference between power and energy. He states power consumption (power is measured in kW) but gives units of kWh which is energy. High school science students shouldn't make that mistake. He presents his total electrical utility charges without segregating the non-space conditioning costs; he's comparing an air conditioner of unknown age and number of stages with a new inverter-driven system, and the new system adds zoning, too. The addition of a zoning system by itself would explain some of the efficiency gains and it confounds the comparison. The other thing that renders the data useless for objective comparison is that we don't know how the cooling capacity of the older unit and the new unit compare with the cooling load of the structure. Most air conditioners are over-sized and simply right sizing the old unit would likely have yielded some improvement in performance. I believe Bosch's inverter-driven systems let you configure the system at any of three different tonnages using an aptly named DIP switch.

That said, you can't estimate the improvement in performance of one system versus another by comparing their SEER ratings unless you're interested in comparing the two systems at an outdoor air temperature of 82F and an indoor temperature of 80F which are the test conditions for the SEER evaluation.

An indoor temp of 80F would result in service calls for me.

SalesEER is utter crap and shame on people for promoting high SEER units to homeowners

The average of the two normal years of 2020 (5,772) and 2021 (5,574) is 5,673

The calculation of the average savings between 2017/2018 and 2020/2021 is:

(10,376 - 5,673) / 10,376 = 45%

Can you explain how the energy savings is more than double that which is predicted by the comparing the 14 and 18 SEER ratings?

Not entirely sure what you're getting at Mike. While the inverter is rated at 18 SEER I believe how the SEER rating is derived doesn't fully grasp the "ramping" function of the inverter. The ramp as it were functions two ways up and down... to search for the best or optimum mode to run in -- it is always searching.

It is difficult to calculate an efficiency metric tied to that because it will vary due to ambient conditions as I alluded to about rain. How do you calculate cloud cover and rain?

Just because the inverter turns on doesn't mean it's only position to ramp up to finish the call. It's desire is to run, not shut off. Longer run times = optimum efficiency it uses less energy because of it. Certainly there are algorithms that can force it to run less, but that's a different conversation than my climate entails.

You can choose averages but the rabbit hole just evolves wider.

In terms of pay back the law of averages only get better as price goes up. If the inverter saves even as little as 40% a higher utility rate will pay for it. To keep it simple 50% of 200 = 100.

50% of 300 is 150. The 200 was when utility rates were .xx per kwh. The 300 is when utility rates rise to .xx per kwh.

What do utility prices normally do? go up. --- they could go back down too.

The whole point of this multi year test planned from the beginning -- to show in detail what I can do. Cooling envy as it were.

The other? I work in hot attics, the last thing I want to do is come home to sleep somewhere that isn't comfortable. I lived with it for about 2 years (single beater AC 14 SEER) to show?

I know there are doubters.

he's comparing an air conditioner of unknown age and number of stages with a new inverter-driven system, and the new system adds zoning, too. The addition of a zoning system by itself would explain some of the efficiency gains and it confounds the comparison.

No, you're wrong as usual Charles.

The comparison was a 4 ton 14 SEER single speed system 10-11 years old (roughly) that was tied to a 4 zone system. ( I did this before I moved in all new duct work + zoning etc it was a planned test from the get go late 2016 time frame)

In 2019 I replaced the indoor air handler + coil added new line set and incorporated the Bosch inverter with those pieces. (the duct work and zone system was already done previously)

I bought this house in 2016 and planned this rennovation from the get go. Planned running this 14 SEER system for at least a few years BEFORE I upgrade to show what the savings "can be" for a home that was built prior to 1980.

That is my business Charles. To show people what can be done. If I do something under handed as you suggest that would be short lived in the real world. I am building something to go back to over and over. Not building it and then telling them good luck.

I know we live in a scam a minute world. This isn't a scam / get AC for free gimmick.

so I did a little digging found this old comparison for heating so you see what I mean in terms of calling this bupkiss for my area when it comes to heating. This climate is too hot to worry about heating for the most part. You still need it, but utility savings aren't the reason for heating here.

The difference is Heat pump vs. Electric resistance heat.

like I said this isn't a scam or gimmick.

Not entirely sure what you're getting at Mike. While the inverter is rated at 18 SEER I believe how the SEER rating is derived doesn't fully grasp the "ramping" function of the inverter.

Ray,

You have presented data which shows at least a 45% savings compared to the savings of 22% predicted from moving from a 14 to 18 SEER rated system. If you removed all the KWH consumption that were used for lighting and other appliances, the savings would be more than 50%.

Therefore your explanation is the SEER rating procedure is flawed in that it cannot accurately measure the power consumption of a inverter type condenser. This is the reason you believe why the Bosch inverter will achieve an energy savings more than double predicted by a change in SEER rating.

Ray,

Certainly the zoning system with a single-stage air conditioner was modified when changed to a variable speed air system. That's just one variable in a series that renders the comparison data suspect if not just plain inaccurate.

Ray,

You have presented data which shows at least a 45% savings compared to the savings of 22% predicted from moving from a 14 to 18 SEER rated system. If you removed all the KWH consumption that were used for lighting and other appliances, the savings would be more than 50%.

Mike you're clearly not thinking...

The power bills from 2018 and before included lighting and all other electrical uses.

The power bills after include all that as well. When I post results I include the total electric bill for the month. The ulitility company doesn't tell me what part of the bill is from lighting and other appliances?

Are you serious? The only thing that changed --- the Inverter AC.

The bill before = everything lights, appliances AC use on a 4 zone system.

The bill after inverter AC = everything lights, appliances AC use on a 4 zone system.

Subtract the two electric bills from the same month with in the year= SAVINGS that pay for the inverter. KISS.

The result from that are savings, because the inverter is energy efficient. It will litterally pay for itself. Just as I have shown. The savings don't come immediate it's over a good number of years, every month you run / operate it.

If you're staying put in the house you live in now... the numbers I show (from a hot climate) if you don't do it, you will pay for it anyway due to those pesky electric bills.

Charles you're a big talker and key board pounder so I wouldn't expect anything different from you. I could easily cut my costs by shutting the AC off completely.

But why would I do that when air conditioning is what I do? This is what I do so I am going to turn around and cheat? I know the realm you are from. I see more cheating from that.

The test was also to show that attaching a cheaper single speed AC to a 4 zone system will work, but there is very little to none effect on efficiency of the machine. Because?

The compressor is still doing the work to create 4 tons of air conditioning. So zoning in the realm of single speed compressors is more about putting comfort where you want it... the purpose of a 4 zone system. (comfort-- you have 4 zones with 4 thermostats) The thermostat now knows what the temperature is in those areas of the house.

So this test of mine... was planned for a myriad of things to show what's what?

The builder is off building a new castle that castle is built claiming this and that from a drawing with no one living in it. Once people move in and start using it... the builder denile and blame game starts. Once people grow tired of that shell game blame game they call Ray, rinse and repeat for 29 years now.

Use the right tool for the right job. Cooling envy as it were, hot climate. You have choices. I just make them a shade clearer. As always your mileage will vary. ( I am speaking to you the reader, not the knuckle heads of this board.)

I service the Katy, Texas area. (whether you like it or not HVAC is a local thing, different climates mean different solutions.)

Solution definition: solves a problem without creating new ones, otherwise it's not a real solution.

"The compressor is still doing the work to create 4 tons of air conditioning."

That's not likely to be the case--ever. Your single-stage A/C was 4 tons for a small 1,900 SF rancher on a slab. It was likely oversized by a ton or more (yes, I know you're in a "tropical like" climate. Like every other single-stage unit, it would have operated in an on/off mode so it cooled air at a rate of 4 tons/hr every time it started up and operated. By contrast, the inverter's claim to fame is that it matches the speed of the compressor to the required cooling load--which could be anything from 0% to more than 100% of the nameplate capacity. To suggest your inverter system was still "doing the work to create 4 tons of air conditioning" is clear evidence you don't know what you're talking about, Ray.

If you had zoning with your single-stage A/C, it's likely you had a bypass damper and duct work which would not be needed with a variable speed air handler. That would reduce static pressure and blower hp required which would increase the efficiency of a system--irrespective of the type of air conditioner installed.

To be sure, inverter-driven air conditioners and heat pumps are more efficient than single-stage units. That said, your data and your presentation are suspect. Houzzers will be well served to look for other information sources when making purchase decisions.

You provide no proof... yet I do. Circular logic Charles only makes you go round in circles.

I know I am set to a higher standard than Charles.

This is why I show proof of a building that is being lived in versus one that is just shown to you on paper. I know Houzzers are smarter than a predisposed builder who wraps himself in arguments he only pretends to know something about.

The pretender versus someone who does it. You have choices. You pick.

Mike you're clearly not thinking...

The power bills from 2018 and before included lighting and all other electrical uses.

The power bills after include all that as well. When I post results I include the total electric bill for the month. The utility company doesn't tell me what part of the bill is from lighting and other appliances?

Ray,

I am thinking clearly and I do understand the utility company can only provide you with a billing statement showing total energy usage. You have to put in a little effort to estimate the amount of electricity consumed for cooling only. With that data you can calculate the percentage of savings to cool your house. You can then compared it with the percentage savings of a SEER 18 system should produce compare to a SEER 14 system. Removing the electricity usage not used for cooling is a more accurate way to calculate the percentage savings compared to your KISS method.

The data you compiled suggests the savings which can be achieved by an inverter type condenser will be twice that is predicted by the SEER rating. This is truly remarkable. Why is it no one at the Air Conditioning and Refrigeration Institute (AHRI) has realized this? I would think the AHRI test engineers could devise a SEER rating test demonstrating the efficiency performance of an inverter condenser.

Mike AHRI doesn't even want you posting that information.

It's a secret. If you post it anyway? You are breaking their own rules.

Let us base a number from a report in a Lab, the number can not be shared or talked about in the open.

With these new found thoughts you may begin to realize why I have done what I have done. The SEER rating I use, is merely to inform you what the equipment is.

The end result is after running it / comparing to what I was paying before using a system that was rated as well. I can't use AHRI numbers post them etc. Legally.

That's right I am here to do this legally. Read the disclaimer of the AHRI sheet again Mike, I pointed this out to you recently yet to this day you continue to ignore it. Yet you stand in front of a judge they will tell you that ignorance of the law is not an excuse you can use.

In a nut shell, wrapped up nice and tight for you. KISS yet again indeed.

SEER and EER walk into a bar.

The bartender asks SEER 'Why the long face'?

SEER says 'I'm 18 under perfect conditions, but in reality, I'm not much better than 14!'

EER says 'I'm usually about 11 regardless of anything'

If you are going to post data showing your inverter condenser achieves twice the expected energy savings, then at least act like a professional and be prepared to defend

So a professional is supposed to ignore the rule of law?

I question your logic Mike.

Post the disclaimer and defend why you do exactly what they tell you not to do and post it anyway.

I believe I did defend it and explain it within the rule of law that I am allowed to do so.

Ray,

You don't need to point to any AHRI document to answer Mike's question. Can you explain why your energy savings is so much more than Mike predicts it should be? Inquiring minds want to know.

Ray,

I posted the certificate so the original author will learn what is the AHRI certificate for his system. I guess your interpretation of the law prevents you from giving your customers a copy of their AHRI certificate. If the posting of certificate is upsetting you I can delete the post. We don't want federal agents questioning you why you are associating with such criminal behavior.

I believe I did defend it and explain it within the rule of law that I am allowed to do so.

I would be interested in knowing what federal or state laws prevent you from providing a better explanation of your data. The AHRI certificate disclaimer has nothing to do with it.

Nothing new Mike. The only difference is that I take my actual results of before and after.

Before I was using a 14 SEER after I am using an 18 SEER inverter.

They make other 18 SEER rated equipment, but those will fair less than the 18 Inverter for reasons I've already explained.

If you don't like the charts I posted search for another chart.

Maybe you'll be happier knowing I wasn't the one who created all these other charts... yet some how I managed similar results in energy savings?

And you still want me to defend my own results when everything I've laid out defends it?

@Austin Air Companie

You should be able to explain the "how" that produces the "what" (the savings,) Ray. That's what a number of folks have asked you to do. Instead of answering that question you've posted graphics that don't even reflect your situation: the first shows savings when upgrading from a 10 SEER system (you've told us that your system was 14 SEER) the second shows savings when upgrading from an 8 SEER system and the third doesn't even state a baseline SEER level so we're left to guess.

That said, you provided the charts, so let's use them. Using the second chart, we can infer the incremental savings produced by increasing the system's efficiency from 14 SEER to 18 SEER (by interpolation.) That's 53% - 43% = a 10 percentage point increase in savings which is 10%/43% = 23% incremental savings produced by upgrading from a 14 SEER system to an 18 SEER system. Your summary of energy savings making the same change in SEER is 45% +/- which is nearly twice what the chart indicates--and it's your chart, not mine. Would you kindly help us understand why your results are twice the level predicted?

What was the old unit? Did it have a PSC or did it have an ECM/X13? What was the average runtime of the old unit vs the new? (HOBO data loggers are a great tool). was the weather 'cooler' or 'warmer' on the new =/= old unit? Did the Thermal mass of your home change? Any insulation work? Was it the same size as the SEER 14 unit? What was the TESP of the old unit vs the new one? (high seer needs lower TESP, about .3wc) Condensor/evap coiled cleaned every year on the old unit? There are so many variables.

By the way, if you're going to plagiarize graphs, at least provide a source.

The three graphs posted above do not show the same savings for a the same SEER rating. This causes confusion. Instead of using graphs, the accepted formula for calculating the savings based solely on SEER values can be used:

1 - (old SEER/new SEER) X 100% = savings percentage

Here is a website which calculates savings based on SEER ratings: www.seerenergysavings.com/

You can enter the old and new SEER values to calculate the percentage. You can also enter a location get get an approximate rate for electricity and run time hours. This will approximate the operating costs of the old and new equipment. Your run time hours could be very different and the estimated costs will not be accurate.

DISCLAIMER:

SEER rating testing is done in a laboratory under ideal installation conditions. The testing is done by the manufacturer and is not certified by a third party agency. The indoor and outdoor temperatures are defined in the test procedure. Most of the temperatures are not realistic summer operating conditions. These test conditions cause the estimated savings based on the SEER calculation to be higher than actual results observed.

The calculator linked above calculates a savings of 22% for upgrading a 4 ton 14 SEER air conditioner to an 18 SEER unit in Houston, TX. The annual cost savings is $216 assuming a rate of 11.11 cents/kWh. That's pretty darn close to the 23% calculated by interpolation of the savings in the graphic. Which brings us back to the question posed to Ray: can you please explain why your savings is twice the calculated savings? Inquiring minds want to know.

the first shows savings when upgrading from a 10 SEER system (you've told us that your system was 14 SEER) the second shows savings when upgrading from an 8 SEER system and the third doesn't even state a baseline SEER level so we're left to guess.

Ha, ha, ha, ha.

I could have only guessed those charts would tie you up in knots.

Like I said, it is nothing new. I was selling 12 SEER systems 20 years ago using the same thing. It's a sales tool. When 14 SEER came out same thing. The higher end SEER systems always came out before they were made law and forcing people to pick them.

When 16 SEER / 18 SEER 2 speed same thing.

If you don't like the charts I provide make your own using your own electric bills as reference points.

We're left to guess? Always an argument with you. I provided you my before and after and you weren't happy with that either.

Ray, there are a lot of variables that can improve efficiency of an HVAC system and lifestyle changes which can lower electric bills. We simply want to understand how your system is able to achieve "off the chart" performance. Inquiring minds want to know.

The equipment is more efficient.

Bosch says their inverter system has a SEER of 18. The calculated savings to go from 14 SEER to 18 SEER is about half what you claim. Is Bosch understating the efficiency or have you figured out a means of getting it to perform better? If it's the latter please share it with us. That would be Ray-mazing! Could it be instead that the 4 ton unit was oversized and/or wasn't performing at 14 SEER? Either would result in overstating the efficiency improvement.

Bosch makes more than 1 unit. Charles.

Yes, Bosch makes more than one unit. You indicated in this thread that your Bosch inverter unit is 18 SEER, so I don't know why you'd debate that point. The question is why the savings you report is twice what would be inferred from the charts you provided. The problem is that you're comparing the performance of an 11-year old single stage 14 SEER air conditioner and a new 18 SEER variable speed air conditioner. We don't know the required cooling load for your home nor whether the 11-year old system was oversized. If it was oversized that would go a long way toward explaining why your savings is much greater than would be predicted. Ditto if it were de-rated for age and mechanical condition.

The problem is that you're comparing the performance of an 11-year old single stage 14 SEER

People don't replace new air conditioners Charles.

"People don't replace new air conditioners Charles."

Of course not, Ray, but comparing the performance of a brand new 18 SEER unit of any make and model with an 11-year old 14 SEER unit of any make and model is likely to overstate the savings compared with a properly performed side-by-side evaluation of new units. The overstated improvement would really be misleading if used by houzzers when making a purchase decision about what SEER unit is best for them.

Like most things, the performance of HVAC equipment diminishes with age. An 11-year old 14 SEER would be equivalent to either a 12.5 SEER unit if well maintained or an 11.2 SEER unit if maintenance was seldom performed. You can find the derating factors here:

nrel.gov/docs/fy06osti/38238.pdf

You can run the numbers using the charts you provided to see what savings you should expect if you properly derated the 14 SEER unit. Of course, you'll need both your shoes and socks off.

Charles has cooling envy.

Ray,

When people are deciding what type and efficiency HVAC system to choose for their home they're typically comparing at least a couple of alternatives. That's what we do with our clients in the design phase.

When evaluating alternatives, the recurring question is what incremental benefit is provided by each level of higher efficiency and what incremental cost is associated with it? The data you've provided don't enable houzzers to make an objective comparison because 1.) you're comparing a new, 18 SEER variable speed system with an 11-year old 14 SEER system (which would perform as either an 12.5 SEER or 11.2 SEER system based on age and maintenance level,) 2.) You've never provided a cooling load (manual J) calculation to confirm the 4-ton 14 SEER system was not oversized (which would result in short cycling and more frequent, elevated starting current and skew the results.) 3.) You haven't indicated what changes you made to your zoning system when going from the old system to the new. A decrease in static pressure which I expect was the case when switching to a variable speed air handler would reduce the required blower hp and skew the results.

If you want to continue to tout the system you installed, just include a caveat so houzzers know you have no credible explanation for why the system performs better other than "it's more efficient."

Yeah Charles has cooling envy real bad.

Love my Bosch.

Choices, choices... yes of course. I offer repairs, and multiple replacement options.

The last thing you want after all that is cooling envy.

If you pick the Bosch I know you'll like it, in more ways than just one.

It's not uncommon for people to be happy with a single speed Goodman that I've installed along with the countless other brands I've used.

Choices? Yes you've got them. This is an elaborate example of the choice I made for my own home.

If it's good enough for my home? When people make this decision they don't tell me... Hey Ray I need to check with my builder before making this change.

I had another customer previously tell me it cut their electric bill in half and this is mystically close to my own records. No one can guarantee what you will see in utility savings.

These are spelled out as well in warranty limitations. You should expect up to 50%. It could be more it depends on a list of various factors as I've laid out some of them in this thread.

It's a choice. I offer other choices. Your (Charles) builder is long gone... he's not coming back if you're considering calling me.

Hit an all time low in the RH department in my office this morning 35% RH LOL. Crisp baby! (how low can we go?)