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Dilemma—replace a good reliable 30 year old A/C or wait to failure

36K views 27 replies 17 participants last post by  skippedover  
#1 ·
This is the 30th season on a two ton split system air conditioner/upflow electric furnace unit which I was thinking about replacing this fall/winter. This unit has served us well with very little repair maintenance. Right now (3pm) our 50 year old 1350 sq. ft. single level house south of Houston near the coast is at 76F & 46%RH. The outdoor temperature is 93F.
My dilemma is: do I replace this fall/winter or continue to run this unit until a major repair needed? It’s not the money to replace but the idea of replacing an old unit that we are very happy with. The only repairs on this unit over the last 30 years is topping off the refrigerant about once every 5 years and the condenser fan was replaced back in 1998. Yes, I know that when failure happens it will probably be in the hottest part of the summer on a holiday weekend. Who knows, it may run many more years. Thinking ahead on what to do if that should happen I think I would buy some cheap windows units to get by until a new split system unit could be installed. What would be the smart thing to do?
 
#2 ·
Replace - has refrigerant leak, probably only 7-8 SEER.

If you use the heat more than a couple of weeks per year, consider a heatpump.
 
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#3 ·
If you're planning on making any changes to the house which could reduce heat loss, do them prior to replacing the unit.
 
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#4 ·
WOW if only the replacement will give you the same amount of service

Of course the extra efficiency of the new unit will result in lower operating costs but what about the owning costs?
New units have more tricky controls that let it work more efficiently, all the things that need to be pampered and can break. Figure what it costs and what it will save and if you do decide to upgrade before it dies, how about bringing your old friend inside and make it an endtable. Put a plant on it or someplace to put the mail. After all after 30 years of faithful service it is part of the family
 
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#6 ·
Amen, Genduct

My experience as a homeowner echos this sentiment. I did buy an early 410a unit--so maybe this is life at the (b)leeding edge of technology.

So when I did the math 6 years ago when I had a heat pump installed I never imagined that I'd be seeing the tech's so often. Where I live, each time it seem to be pay for a diagnostic visit, then another visit to install. Been a visit almost every year. Seems almost like I exchanged otherwise lower heating bills for an additional annual electric bill that I send to my HVAC company. But maybe I was just unluckly.

10 year warranty on parts seems great, but in my case the (free) parts have been a vanishingly small fraction of the costs. I would suggest you consider asking for a 5 year warranty that includes labor--maybe if the thing makes it out of the infant mortality period okay, you'll have better luck than I did.
 
#7 ·
ask for all quotes to include labor and parts warranties. most companies offer that insurance with the purchase of equipment.
slightly raises the purchase price of equipment, but pays the mechanic for any service during the warranty!
amana even has a 25 year warranty I think. and if the compressor fails under that warranty, they give you a new system... gotta get specs on that one to be sure.
anyway, point is, a new system does not have to set you back with warranty issues.
also, get the highest recommended company to install the system. installation is the KEY to a long life system.
regular service is critical for prolonged life of the equipment as well.

your 30 year old system is likely costing you double what a new system will to operate.

be sure to have your old ductwork inspected and upgraded/sealed as part of the install.
and be sure and have a load calc done on the house including the ductwork modifications.
 
#8 ·
If you have the funds, I recommend you start planning on replacing the AC in the fall. Start doing the research now and begin interviewing HVAC contractors so you will be in a position to do this between the cooling and heating seasons. You will also have time to research local and manufacturer's rebates. Having the installation done with no time pressure is a much better option.

The money you would spend on buying window units can be put towards the purchase of your new system. I know you want to squeeze every hour of life out of the unit, but overall you are better off retiring it under your own terms. In addition you will have more years to enjoy your new equipment.
 
#9 ·
Thanks for all of the good advice. According to my math the EER for my old unit is ~8. My small house is all electric. Lets say all of our electric bill was due to A/C & heating and I was able to cut it in half year around with a new efficient unit, I could not justified a new unit on that basis alone. Nor could I justify a new unit based on passed repair maintenance history. Last time an A/C tech was out was in 2006 to add a little refrigerant. As been implied, due to the more sophisticated electronics on a new system my visits by an A/C tech might be somewhat more frequent.

I am researching systems and equipment. My biggest, hardest, and most subjective task will be selecting a HVAC contractor for the install.

Thanks again for the input------
 
#10 ·
Well it all depends on your spending habits. For example, do you drive your car until the engine dies or do you replace it when it hits a certain age or mileage? What about painting your home? Do you paint it when it looks a little drab or do you wait for the last flakes to fall off first? How about your clothing? Keep it stylish for the times or are you still wearing the 1980's stuff?

It's less about what we can't predict and a lot more about how you run your life. Certainly you've noticed the vast improvements in electronics, cars, phones, T.V.s, and a myriad of different things over the last 30 years or so? Do you think perhaps the HVAC industry may have also made some progressive changes?

In our area, in days gone by, heating boilers used to be huge. I mean really, really BIG! The bigger the better was the way it was. But then the cost of fuel went up and some folks began to see things differently. Now the boilers can be carried in by one man and hung on a wall! People heat their homes using only 50% or less of the fuel used previously. Same goes for AC systems.

If you're in hot weather country, moving up to an 18-SEER AC system will certainly cost you some acquisition costs but your operating efficiency will improve substantially so you'll use on the order of 50% or less of what you spend now. And you'll be much greener. That is, you'll lose green (money) on the purchase but you'll gain green points for using less electricity! Doesn't that make you feel green with envy for all those folks who've already done their part at saving the planet?
 
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#11 ·
If it ain't broke, why replace it?
While you'll get better efficiency from a new unit, it is still cash out of pocket.
Maybe investigating new units, getting quotes and load calcs done(paying if you want an actual Manual J ran) is a good start.
That way when your unit, a good one it seems, finally does conk out, you won't be unprepared.
Speaking as a person who drives a 1984 Jetta, lol.
 
#12 ·
Reply to skippedover

Well skippedover, you left out a few factors about being green. What about all of the energy (fuel) used in the manufacturing of new equipment? What about all of the fuel used in shipping, delivery, install, etc? What about all of the effort to dispose of old equipment (recycle, landfill, etc.)? Is it really green to replace old less efficient reliable working units with new efficient sophisticated designed units utilizing the latest technology (assuming there is no return on the investment)? I’m betting a carbon footprint analysis says no.

As far as being familiar with really big boilers, I spent 35 years in power generating plants with some really really big boilers supplying steam to some really big turbines generating 100’s of megawatts. I mean really big boilers. I won’t even mention some of the sophisticated electronic controls and auxiliary equipment it takes to keep these monsters running.

I thought I had heard it all in my lifetime, folks need to stay in style by replacing a older perfectly good running unit with the latest technology? Surely you jest?? You are in sales, right?
 
#28 ·
Well skippedover, you left out a few factors about being green. What about all of the energy (fuel) used in the manufacturing of new equipment? What about all of the fuel used in shipping, delivery, install, etc? What about all of the effort to dispose of old equipment (recycle, landfill, etc.)? Is it really green to replace old less efficient reliable working units with new efficient sophisticated designed units utilizing the latest technology (assuming there is no return on the investment)? I’m betting a carbon footprint analysis says no.

As far as being familiar with really big boilers, I spent 35 years in power generating plants with some really really big boilers supplying steam to some really big turbines generating 100’s of megawatts. I mean really big boilers. I won’t even mention some of the sophisticated electronic controls and auxiliary equipment it takes to keep these monsters running.

I thought I had heard it all in my lifetime, folks need to stay in style by replacing a older perfectly good running unit with the latest technology? Surely you jest?? You are in sales, right?
You're quite correct. I'm not a 'green' specialist so going to the n'th degree to figure out if I should eat breakfast of fruits nor nuts just isn't in my normal thought process. I do sell, yes but I'm primarily a service tech/business owner. And I'm also sick and tired of people asking for a "pay back" on their HVAC equipment. Of all the items that a person purchases in a year, the number that provide any savings at all is tiny in comparison to the total. From clothes to gasoline, cars, cell phones, big screen T.V.s, soap, toilet paper! I could go on all day and still hit almost nothing the really provides and savings at all, let alone 'pay back'. Upkeep for the home will pay back something (hopefully, though not as much today as 3-years ago) when you sell the home and cash out. Otherwise, why do people purchase? How many people would actually suffer or be unable to exist without a cell phone? Internet connection? Car with leather interior?

My point is, pay back should NOT be the holy grail of purchasing HVAC equipment. Nobody has saved anything when it comes to vehicle emissions. Yet the atmosphere is arguably cleaner as a result of everyone being forced to operate 'cleaner' engines and low or no lead fuels. Who among us would have volunteered to purchase such an advanced automobile engine, given the high level of computer control, etc. when we could have continued with our old high octane engines of the past? I submit nearly no one.

And low price certainly isn't the monument to which all persons worship if the Yugo automobile is any indicator. It was the original throw away automobile that the price conscious should have purchased by the million! But alas, it went entirely away. And what's the payback on the Corolla that someone purchased rather than a Yugo?

You purchase a car for, in most cases, substantially more than the HVAC system you'll put in your home. Yet the car will do very little work for you most days. You'll perhaps drive it to work in the morning, it sits in the lot all day, drive it home at night where it sits. If you've got a long commute, that's maybe 2-hours out of 24. 7-years = 61,320 hours. Of that, based on 2-hours per day of use, your car, for which you paid considerably more, operates a mere 5,110 hours or 8.33% of the time. Had you purchased your HVAC equipment the same day you purchased your car, it would have operated on average (adjusted for seasons) 8 to 10 hours per day, whether you're home or not! That's 20,440 to 25,550 hours or 33.33% to 41.67% of the time AND that HVAC equipment will operate on the order of 15+ years.

It should be a matter of perspective. Which has more value? The granite counter tops, big screen t.v., smart phone? Or a reliable, reasonably efficient HVAC system? I can't make that determination for folks but I owe it to my prospective clients to at least try and raise their awareness.
 
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#13 ·
As been implied, due to the more sophisticated electronics on a new system my visits by an A/C tech might be somewhat more frequent.
Basic straight cool units don't have sophisticated electronics - manufacturers increase efficiency primarily by using larger coils.
 
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#26 ·
Basic straight cool units don't have sophisticated electronics - manufacturers increase efficiency primarily by using larger coils.
This is absolutely, positively, 100% correct - heat transfer efficiencies that is. The controls merely turn it on and off but can but not always contrubute to decreased operating costs.
 
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#14 ·
Do diligence performed at your leisure will pay huge dividends. The greatest risk faced when there is a gun to your head is missed opportunities. Next is rushed bad design.

How much do you spend per square ft/year on energy? This tells opportunity size, and if you are already paying for improvements you don't own, sending energy co executives to Fiji for holiday.

Do you have comfort issues you'd like solved?

Lots of things to consider when you have the luxury of time to learn. Take your time and figure out what you want, what it will save you and the when will be obvious. Let us know, after doing the numbers, if when is at next expensive repair or sooner?
 
#15 ·
as most of the posters have said,you are in a great position to fully examine your needs,the various equipment that is out there and most importantly the contractors and their reputations.
When you are looking at equipment i would suggest that if a feature looks intreging to you and it just came out this year,keep your eyes and ears open to that feature real close.If you had come through the era that a lot of us have come through you would develop an evil eye toward it until it is field proven.
Ten year parts and labor extended warranties are a very good thing to have for the newer higher tech equipment.
That however reminds me to tell you to investigate the procedures of that warranty so that you don't have to pay first and then get a credit a month later or that you're covered on holidays and night time calls.
Most equipment have local wholesale representation so repair parts and other services are near you.There are a few where thev manufacturer only ships fron 4 or 5 places around the country and a needed part may take 2-3 days to get.Investigate.
When looking at a contractor,ask for the names and addresses of 4-5 people who have had the same equipment installed as you are being quoted.And Call them about the job and the workers etc.
So now in the comfort of your home begin the relaxing search.When you find everything you are looking for put that info in your top drawer and when the very timely death happens all you have to do is get your info out and make the deal.
good luck
 
#16 ·
Same dilemma. GE in its 30th season. Never added refrigerant. Still keeps the upstairs cool even though now it only cools the return air 10-13F. Only repairs - contactor replaced twice. I bought the part and replaced it myself. Also replaced some deteriorating wires connecting to the contactor the second time I replaced the contactor. Only maintenance has been to clean the condensate line. I replaced its downstairs twin when it was 20 years old - leak in the evaporator coil.

Are there any early warning signs of impending failure of the compressor/condenser/evaporator?

Is there a particular time of the year when I can expect manufactuer's incentives, lower prices?

Is it better to have the installation done in spring or fall, when the attic temperature will be moderate?

A new unit will likely require more repairs and wont last thirty years. Is there a brand or line within a brand noted for minimal need for repair and long life?
 
#17 ·
Unless your electric bills are unreasonable (compare with neighbors of similar size homes) I'd run it into the ground. I have a 10yr old over-sized unit and am unable to justify replacing it based on energy bills.
 
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#19 ·
-1

You have a huge opportunity, time to plan, to build your specification.

The horror stories are predominantly from people who failed to plan, you know how that goes, it's like planning to fail. Design was rushed and usually somewhere between nearly and completely thoughtless.

Take your annual energy spend and x20, that's a big number that may have significant opportunity attached. If you are caught off guard, kiss the opportunity to dig into that goodbye.

Build your plan now. Also assess cost of keeping vs replacing with the design you settle on, that will determine if you should let the current system run into the ground, which may be the best course. But right now that is complete hypothesis. Until you look into it you are ignorant, correct?

I know some say ignorance is bliss, but when is ignorance really the best approach when faced with large, long term decisions.
 
#20 ·
Another consideration is how sure are you that you will be living in the house long enough to get payback on the newer system?
 
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#21 ·
You think a house with 30 year old equipment will draw the same $ as a house with brand new equipment? Guess that depends upon the market and audience.

I think you'll knock out a whole lot of first time homebuyers worried about having no $ for repairs after finding a downpayment. If that is your market, and you sell in 4 years, you are likely replacing equipment at sale to make the sale.

Which is better "payback", nice equipment at today's prices and 4 years of energy savings and a house with lower energy history, or no energy savings and equipment prices 4 years from now and a house with higher energy history?
 
#22 ·
Most buyers around here are more concerned if it works or not and are trying to buy for the least $$$ per sq ft. A newer unit might bring a little more but not nearly enough to offset the cost of the equipment/installation. The average buyer doesn't even think about HVAC until it's hot/cold in the house or they have really high utility bills. Sadly most buyers are more concerned with a stain in the carpet or what color the walls are than the age/condition of the mechanical systems.
 
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#23 ·
Interesting discussion. Someone mentioned autos a few posts back as a comparative study. It is clear that in the last 25-years, cars have become more efficient, safer, more comfortable, more complicated, more expensive, require less maintenance and - I think the statistics bear this out - more reliable.

I think you can say the same about HVAC systems, with the exception of their reliability and, possibly, maintenance. My perception from reading here and elsewhere is that the HVAC industry, while making great strides in all of the other areas, has gone the other direction with regards to reliability.

So the question is, has the HVAC industry actually regressed in the area of reliability or is that an incorrect perception? Secondly, if it has regressed, is it due to the quality/longevity of the manufactured product, the quality of installation or a lack of maintenance?
 
#24 ·
Not sure it's a fair comparison. A car is an independent system of systems. Hvac is a system that is highly dependent on external systems being in balance.

Imagine driving your car with the emergency brake 50% engaged, or with one square wheel, not changing the oil but every 100,000 miles, would reliability issues be any surprise? There are so many extraneous factors i don't think its fair to say its the equipments fault.
 
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