What to do with 26 year old central AC unit?

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pb1996
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What to do with 26 year old central AC unit?

Post by pb1996 »

26 year old central AC. Working well. I had been paying for annual "routine maintenance", they seem to just charge me $150 to document everything is in good working order. It doesn't appear they do any "tuning up" or anything.
Should I stop having these annual checks and just wait for it to stop blowing cold air before I call someone in? (I'm assuming at that point a new unit is in order...)

Thanks!

Pb
livesoft
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Re: What to do with 26 year old central AC unit?

Post by livesoft »

We have 2 complete central AC systems: one for the upstairs and one for the downstairs. They are 28 years old. We do not do annual maintenance and never have. We only have them fixed when they break which is simple stuff like a relay or a capacitor except for the time when lightning "blew up" an outdoor unit leaving the one next to it completely undamaged.

Your assumption about replacing just because it stops blowing cold air is a false one. For instance, a repair part costing less than $50 could be the problem and easily fix that.

And we have NEVER had the "fins" cleaned though we keep vines from growing up and around the outdoor units.
Last edited by livesoft on Wed Mar 31, 2021 9:30 am, edited 2 times in total.
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Polymorphic
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Re: What to do with 26 year old central AC unit?

Post by Polymorphic »

The company that does my annual tuneup will clean the condenser unit fins with a hose, which keeps it operating efficiently. You can do this yourself (just pull the power first!) if your time isn't worth more than the service call.
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djpeteski
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Re: What to do with 26 year old central AC unit?

Post by djpeteski »

I think the annual maintenance on AC units is a scam. Mainly they are already there if something needs fixing and will likely gain your business.

A lot of AC repair can be done yourself a much lower costs. The most egregious was my last suggested repair. AC is not quite working right, and I have the dude diagnosis it for $100. Bad circuit board/relay. We can replace it for $600 or you should probably just get a new unit for $8k as it is 16 years old already.

I found the part on Amazon for $60. It took me less than 5 mins to replace.
acegolfer
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Re: What to do with 26 year old central AC unit?

Post by acegolfer »

djpeteski wrote: Wed Mar 31, 2021 9:27 am I think the annual maintenance on AC units is a scam. Plus they are already there if something needs fixing

A lot of AC repair can be done yourself a much lower costs. The most egregious was my last suggested repair. AC is not quite working right, and I have the dude diagnosis it for $100. Bad circuit board/relay. We can replace it for $600 or you should probably just get a new unit for $8k as it is 16 years old already.

I found the part on Amazon for $60. It took me less than 5 mins to replace.
Agree. AC annual maintenance consists of outside condenser fin hosing, inside evaporator fin cleaning, condensate pipe flushing. Anyone can do it.

I've replaced parts in my AC. But never replaced the board/relay. Which part did you get from Amazon?
daheld
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Re: What to do with 26 year old central AC unit?

Post by daheld »

There is absolutely zero reason to pay anyone for annual maintenance on a central AC unit. None. At all. You can spray the condenser with a hose once a year. You can change filters. That's all you need to do. There are a couple things that are very, very slightly more involved but you don't have to do those things. Especially if it's 26 years old. Just let it be.
tibbitts
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Re: What to do with 26 year old central AC unit?

Post by tibbitts »

I had a similar-age unit and replaced it while it was still working properly. So that's what I'd do in this case.
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threebuns
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Re: What to do with 26 year old central AC unit?

Post by threebuns »

Mines going on 30 yrs old. I have a friend who does HVAC stuff, I have him over every 2 yrs or so to make sure it is still okay. He says it's fine, it will slowly draw more power but it will likely run for maybe 5 more years. He also charges it, which I think is the only thing you should do every so often.

I clean the fins at the end of each season (takes probably a half hour) and cover the unit with a tarp in the winter.

I will replace it when it is totally dead. Worst case scenario, it dies in the dead of summer (Missouri) and I either go stay at a friends/hotel, get a window unit, or just setup some fans and survive until it gets replaced.
alfaspider
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Re: What to do with 26 year old central AC unit?

Post by alfaspider »

tibbitts wrote: Wed Mar 31, 2021 9:51 am I had a similar-age unit and replaced it while it was still working properly. So that's what I'd do in this case.
If it was a high quality unit when purchased, I don't really see the sense in it. I ran the numbers for my 22 year old unit. It was about the highest efficiency unit you could get when new (14 SEER). I was quoted $14k for a new 18SEER unit. Running the numbers, I determined a new unit will basically never pay off in energy efficiency. I can get some comfort benefit by getting a dual speed compressor (lower humidity), but that's about it.

The only real benefit of a new unit is less worry about it going out on a 100F day in July. But even a newer unit can have issues. There's not too much in an air conditioning system that absolutely can't be fixed. Biggest barrier to continuing to repair an old unit is that the old R22 refrigerant will eventually become too costly to justify replacing in the event of a leak. Worst case scenario is I need to shell out for a new unit this summer.

Anyhow, the plan is to run the old unit for at least a few more seasons. R410a (current refrigerant) is scheduled for phase out, and it would be nice to get one with the newer refrigerant. That way, I'm not in the same position in 10-15 years as I am with my current unit using an obsolete and expensive refrigerant.
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beyou
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Re: What to do with 26 year old central AC unit?

Post by beyou »

daheld wrote: Wed Mar 31, 2021 9:48 am There is absolutely zero reason to pay anyone for annual maintenance on a central AC unit. None. At all. You can spray the condenser with a hose once a year. You can change filters. That's all you need to do. There are a couple things that are very, very slightly more involved but you don't have to do those things. Especially if it's 26 years old. Just let it be.
I don't want to touch my AC, no interest whatsoever.

And I have one contract that covers heat and AC. The only reason I pay it is this gets you to the front of the line for emergency service.
My guy came to my house on a cold winter night to fix our furnace rather than be cold all night waiting for service next day or worse.
I know this does not save me money vs cost of self-maintenance, in fact I often don't even bother calling to schedule annual inspections that are included in the contract. But I know the service is available 24x7 and the guy who installed my systems will come and fix if they break down.

To each his own, I generally do not buy service contracts or extended warrantees as I would rather pay later than pay now.
But heat and AC usually break down on very hot or very cold days, when you can least tolerate such outage and when others are calling for service.
finfire
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Re: What to do with 26 year old central AC unit?

Post by finfire »

My AC maintenance is 2/year, costs $200/year.

Worth it. I have zero interest in messing up my AC.
daheld
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Re: What to do with 26 year old central AC unit?

Post by daheld »

beyou wrote: Wed Mar 31, 2021 10:09 am
daheld wrote: Wed Mar 31, 2021 9:48 am There is absolutely zero reason to pay anyone for annual maintenance on a central AC unit. None. At all. You can spray the condenser with a hose once a year. You can change filters. That's all you need to do. There are a couple things that are very, very slightly more involved but you don't have to do those things. Especially if it's 26 years old. Just let it be.
I don't want to touch my AC, no interest whatsoever.

And I have one contract that covers heat and AC. The only reason I pay it is this gets you to the front of the line for emergency service.
My guy came to my house on a cold winter night to fix our furnace rather than be cold all night waiting for service next day or worse.
I know this does not save me money vs cost of self-maintenance, in fact I often don't even bother calling to schedule annual inspections that are included in the contract. But I know the service is available 24x7 and the guy who installed my systems will come and fix if they break down.

To each his own, I generally do not buy service contracts or extended warrantees as I would rather pay later than pay now.
But heat and AC usually break down on very hot or very cold days, when you can least tolerate such outage and when others are calling for service.
Yeah, see the thing is there is quite literally no maintenance that absolutely has to be done. It's a matter of spraying the condenser off with a water hose, which takes about 4 minutes, and changing filters. I'm not sure either of those actually even count as maintenance. The "being at the head of the line" is a psychological thing that is almost never going to be needed.

Like you said, to each their own, but I just don't get it. I'm not like psychotically frugal or anything, it just quite literally is not a needed service.
tibbitts
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Re: What to do with 26 year old central AC unit?

Post by tibbitts »

alfaspider wrote: Wed Mar 31, 2021 10:01 am
tibbitts wrote: Wed Mar 31, 2021 9:51 am I had a similar-age unit and replaced it while it was still working properly. So that's what I'd do in this case.
If it was a high quality unit when purchased, I don't really see the sense in it. I ran the numbers for my 22 year old unit. It was about the highest efficiency unit you could get when new (16 SEER). I was quoted $14k for a new 18SEER unit. Running the numbers, I determined a new unit will basically never pay off financially. I can get some comfort benefit by getting a dual speed compressor (lower humidity), but that's about it.

The only real benefit of a new unit is less worry about it going out on a 100F day in July. But even a newer unit can have issues. There's not too much in an air conditioning system that absolutely can't be fixed. Biggest barrier to continuing to repair an old unit is that the old R22 refrigerant will eventually become too costly to justify replacing in the event of a leak. Worst case scenario is I need to shell out for a new unit this summer.
What I did made sense to me and is what I did. It wouldn't even be a close call to me.

I would agree that I would not consider efficiency as a deciding factor, although it's a nice bonus if it saves a small fraction of the installation price. In my case I went from what I believe was 10SEER to 14SEER, although given the physical condition of the older unit I can imagine it not be quite up to the original rating. My electricity costs were reduced, but not nearly enough to pay for the new unit.
Last edited by tibbitts on Wed Mar 31, 2021 10:51 am, edited 1 time in total.
Icamp
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Re: What to do with 26 year old central AC unit?

Post by Icamp »

If it's 26 years old I'd wait for it to die. Proactive maintenance has probably kept it it alive this long but sometimes it's no longer cost justified.

I'm sort of laughing at the folks who say it's not necessary. There are some of you who don't even change your furnace filter once a year. Covering the AC over winter invites rodent to enjoy the shelter too and they like to chew wires. I would also much rather find out my capacitor is getting weak and get a new one installed before a heat wave than finding out the hard way during a heat wave.
UpstateNY86
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Re: What to do with 26 year old central AC unit?

Post by UpstateNY86 »

Also need to have drains flushed annually, or else very well could backup and cause damage nobody wants to deal with. AC contractor also inspects for any burnt wiring, charge, and make sure everything is running in good working order. Also, never just replace a unit on a whim because it stopped working. A lot of broken units can be easily fixed.
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lthenderson
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Re: What to do with 26 year old central AC unit?

Post by lthenderson »

pb1996 wrote: Wed Mar 31, 2021 9:21 am 26 year old central AC. Working well. I had been paying for annual "routine maintenance", they seem to just charge me $150 to document everything is in good working order. It doesn't appear they do any "tuning up" or anything.
Should I stop having these annual checks and just wait for it to stop blowing cold air before I call someone in? (I'm assuming at that point a new unit is in order...)
In 30 years of air conditioning units, I have never had any one perform maintenance unless it stopped blowing cold air. The caveat is that I do the maintenance which is just cleaning the air filter monthly and cleaning off the condenser coils every spring. Takes me about a half hour to clean the coils once a year and maybe five minutes a month to clean the filter. One can use disposable filters and cut that down to a few seconds.
keystone
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Re: What to do with 26 year old central AC unit?

Post by keystone »

This is a question I have often pondered as I have a 27 year old Bream in my house.

I have come to the conclusion that the best strategy for my household is to just keep fixing things that break and only replace it when I absolutely have to. I also no longer believe in regular maintenance beyond periodic replacement of filters.

Several years ago a technician told me that I would get my money back by replacing the system due to improved energy efficiency. I crunched the numbers and realized that there is no way this is even remotely possible. My monthly utility bills at the absolute highest are less than $200 per month. I suspect I would not save much more than $20 a month in reduced energy bills.

Several technicians have told me that modern systems do not last as long as they do compared to units built in the 90's. I believe it based on anecdotal evidence from friends and family. This is all the more reason to stretch out as much life as you can from your AC unit.

My wife is a little uneasy about having such an old system in our house. I have assured her that we can easily afford to stay in a hotel given all of the money that we have saved over the years, if and when our unit breaks down during a heat wave.
squirm
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Re: What to do with 26 year old central AC unit?

Post by squirm »

I would never pay for an annual "maintenance" or whatever they do. Wait until something breaks. I do simple things on ours, we have two units one for upstairs and one down. when a capacitor blows, i replace it, or the evaporator unit needs cleaning, blah blah blah. 22 years, is about the age of ours, i'm thinking about replacing it, the new units are much more efficient, but it's low priority.

what nice if you have two units, you can swap parts. during one heat wave the unit to the bedroom broke, which is more important then the downstairs one, so i just swapped parts. when the new parts arrived i just put them in the downstairs unit.
dukeblue219
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Re: What to do with 26 year old central AC unit?

Post by dukeblue219 »

We never did annual maintenance until we finally did, and then 4 months later suddenly had a significant R-22 leak that led us to replace for a much newer and more efficient unit. I'm not implying that the maintenance caused the leak, just that it didn't magically stop it from happening.

My folks have had spring and fall "tuneups" for 30 years and have more problems with HVAC than anyone I've ever known.

I'll settle for fixing when it breaks and maybe, maybe have someone take a look if it's been many years without a service visit.
carolinaman
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Re: What to do with 26 year old central AC unit?

Post by carolinaman »

I pay $195 annually for twice a year service, once for gas heat and other for AC. The guy I use is a one man company recommended by my son who uses him for businesses, condos and homes he maintains. He is very practical and will never recommend something that does not need to be done, unlike these big companies that advertise on TV and have commission based techs. Also, this guy is very responsive when I call him.

I am not as handy as some of you and find this a reasonable service. If not comfortable servicing these units yourself, IMO you need to have a relationship with a company you trust and that will promptly respond to your needs.
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Watty
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Re: What to do with 26 year old central AC unit?

Post by Watty »

I have had annual maintenance done because that was required to get a ten year parts and labor warranty that came with AC and furnace with I replace them at the same time. I am just about at the end of the ten year warranty.

One thing that does is that it gets me priority if I ever do have a problem. So far I have had to call them for the AC twice, both were on some of the hottest days of the year. My experience was;

1) Called at about 8 PM on Memorial day. They were out and replace a condenser before noon the next day. I know you can do that yourself, but I was able to go to work and wife was there to handle the repair call.

2) Called them at maybe 8:00 AM on a weekday, they were out around 3:00 PM for a problem with a motor. (It actually took two visits, a temporary fix and then they returned a day or two later with the replacement motor.)

These were both on very hot days so if I had call to get someone to come out it would likely have been very difficult to get an appointment and I would likely have been charged a very high price.
pb1996 wrote: Wed Mar 31, 2021 9:21 am charge me $150
That sounds high if that is just for one AC unit.

I just have one unit and mine only costs about $160 a year for the maintenance agreement and they come out in the spring to check the AC and again in the fall to check the heating.

I am hardly wealthy but for me the convenience is worth it and if I am going to do some DIY projects I will do things that have a bigger payback. It also gets me out of the loop so if there is an AC problem on an 90+ day that my wife will not think I am in any way responsible. It is a lot different than if the something like dishwasher out of service for a week.
What to do with 26 year old central AC unit?
What your local climate is like and what your budget is like is important in deciding what to do.

One other issue you have is that an AC that old likely uses the R22 refrigerant that they stopped manufacturing this year. I am not sure where it is at now but that could make fixing any problems more expensive since they would need to use stockpiled or recycled R22

If you live in an area where it would be a real hardship to go a week without AC in the summer then I would look at getting bids to preemptively replacing it to see if you can get a good price.

The problem is that if you wait until it fails on a 90+ degree day in August then you will get a real high price, if you can even get someone out to install it in a reasonable amount of time. I once had to replace a failed water heater where I had to pay a premium price to get done because I had few other options.

It will vary with your local climate but there is usually a gap in the spring and fall between the heating and cooling season when HVAC companies are not very busy. I have twice, in different houses, gotten bids for replacing HVAC systems in September when the companies were not very busy. That allowed me to easily get four or five bids and when I called they were usually out the next day to give a bid. They also know that I was under no pressure to install a new system since I was doing a preemptive replacement. Especially with one company I got a very good bid for good equipment since they were looking for work to keep their crews busy.

I am sure that by being able to take my time and get multiple bids I was able to save a lot of money compared to buying a new AC on a hot day when I was under a lot of pressure to replace it quickly. That more than made up for not getting a few more years service out of the the old system. It did not track it carefully but there were also some modest energy savings and the new systems were a lot quieter and more comfortable.

When I selected a company they actually wanted to install it the next day since they had a crew available. The crew that came out also seemed to do a very good job and took the entire day to install both a new AC and furnace and they were in no rush to finish up since they did not have other customers to see after me.

I was also able to schedule a day off work to be there when they were installing it.
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Re: What to do with 26 year old central AC unit?

Post by tibbitts »

carolinaman wrote: Wed Mar 31, 2021 11:31 am I pay $195 annually for twice a year service, once for gas heat and other for AC. The guy I use is a one man company recommended by my son who uses him for businesses, condos and homes he maintains. He is very practical and will never recommend something that does not need to be done, unlike these big companies that advertise on TV and have commission based techs. Also, this guy is very responsive when I call him.

I am not as handy as some of you and find this a reasonable service. If not comfortable servicing these units yourself, IMO you need to have a relationship with a company you trust and that will promptly respond to your needs.
I somewhat agree but I'm not sure whether a one-person company is the best solution for that. How does he deal with coverage when he's not around, maybe for weeks at a time?
livesoft
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Re: What to do with 26 year old central AC unit?

Post by livesoft »

Icamp wrote: Wed Mar 31, 2021 10:18 amI'm sort of laughing at the folks who say it's not necessary. There are some of you who don't even change your furnace filter once a year. ....
That's me! Haven't changed a filter since 1995! Of course, we use washable filters and they do get cleaned every once in a while. Our filters are an odd size that cost a few bucks per disposable filter instead of a few cents, so going with a permanent filter back then has saved us hundreds of dollars. I can toss the filter on the carpet and vacuum it with the rotating carpet brush of the vacuum cleaner doing a great job.
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Californiastate
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Re: What to do with 26 year old central AC unit?

Post by Californiastate »

I'm considering replacing ours with a new variable compressor and system. Ours is approaching 30 years old. I don't pay a maintenance contract. I change the filters every 3 months. That's it. I'm considering changing it because of the way it runs. It runs full bore until it reaches temp and then it shuts off. Rinse and repeat. A variable system system will modulate the compressor and won't cycle as much. It will be more comfortable. I'm at a time in my life where being financially comfortable is allowing me to be physically comfortable. I haven't made the move on the AC yet but the argument is leaning that way.
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Re: What to do with 26 year old central AC unit?

Post by wfrobinette »

Polymorphic wrote: Wed Mar 31, 2021 9:26 am The company that does my annual tuneup will clean the condenser unit fins with a hose, which keeps it operating efficiently. You can do this yourself (just pull the power first!) if your time isn't worth more than the service call.
Why would one need to pull the power first?
tomd37
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Re: What to do with 26 year old central AC unit?

Post by tomd37 »

I believe in HVAC system annual maintenance. I pay $75 in spring and again in fall for the servicing of two units; a gas pack unit for the first floor and a split system for the second floor. At age 84 I am not tackling that type work myself as I value my life too much. :wink: I do replace the air return filters every two months.
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harrington
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Re: What to do with 26 year old central AC unit?

Post by harrington »

pb1996 wrote: Wed Mar 31, 2021 9:21 am 26 year old central AC. Working well. I had been paying for annual "routine maintenance", they seem to just charge me $150 to document everything is in good working order. It doesn't appear they do any "tuning up" or anything.
Should I stop having these annual checks and just wait for it to stop blowing cold air before I call someone in? (I'm assuming at that point a new unit is in order...)

Thanks!

Pb
I worked in heating and cooling and I can honestly tell you these annual checkups are nothing more than a money grab. Call them when they don’t work. It was a joke in the industry that they clang a few pipes, shine a flashlight around and turn a vacuum on :D
illumination
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Re: What to do with 26 year old central AC unit?

Post by illumination »

Stop having annual checks. Even the guy I use that's been doing HVAC for like 30+ years and gets paid to do it thinks it's incredibly dumb to hook gauges up to a perfectly working unit. Good idea to clean the fins yourself every once in a while, just do something really mild like dish soap and water and don't worry about getting it 100% clean and damaging something in the process.

It's great if you have an honest tech, but you're not only inviting trouble just having someone open up a sealed system, I've seen first hand the sort of games they play. Years ago I had an elderly grandmother get a low cost check up, guy checked the capacitor and said it tested bad, wanted like $300 for a new one. The part itself was like $8, old one worked fine.

If you take your car into a repair shop and ask a mechanic to find something wrong, most will come back with a list.
ragnathor
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Re: What to do with 26 year old central AC unit?

Post by ragnathor »

This post has been quite useful. I was debating whether to get annual checkups but now I won't.

Any tips on knowing a competent/honest tech from one who's not for someone HVAC illiterate? I had a reputable company come 6 months ago and charge 200 repair and 600 for Freon (claimed they tightened some expansion valve). Same problem recurred with near empty Freon - gave me another 800 estimate to refill and diagnose with a dye test, and repair would be unknown additional amount.

I had another guy come, found leaking copper tubing which he fixed and replaced the Freon for 500 total.
vested1
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Re: What to do with 26 year old central AC unit?

Post by vested1 »

Although I'm new to the heat pump world, having moved from a location in CA that didn't even need insulation in the walls, I see value in our twice yearly maintenance visits. We have two systems, one for upstairs and one for downstairs. The techs visits in the spring to check AC functionality an in the fall for heating. They do more than spray the fans.

I shadowed them on their visits. They do compression test to determine if there is any leakage. They check the traps and clean them out and measure the current in a couple of places when the systems are operating to gauge efficiency. Last fall they found that the older unit, 16 years old now, needed 2 pounds of refrigerant, and added it for an additional cost. They also change the filters, although I check them periodically too.

The cost is $220 a year, which includes the inspections for both systems with two annual visits. Money well spent IMHO.
Designairohio
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Re: What to do with 26 year old central AC unit?

Post by Designairohio »

To OP
Call a local Hvac supply house and ask for the counter, ask the counter person if they can recommend an honest well trained small company. These counter people know the good guys from the bad. Have a thorough assessment of your unit and make your decision from there
A good tech will always hook up the gauges and measure the line temperatures, he will be measuring the superheat and sub cooling of the system, putting gauges on without measuring the lines can lead an untrained or unscrupulous to a false diagnosis. For example low pressure could make him think it’s low on refrigerant so he fills it up, now it could be overcharged, however if he reads low pressure and has low superheat this indicates an airflow problem. An 1/8” of dirt built up on a blower wheel can reduce airflow through your ductwork by 30%.

within a few minutes he can tell if you are low on refrigerant, if one of your coils as are dirty if your filter is dirty or some other air flow problem. He can also test capacitors, contactors, amp draw and voltages.

Many of the people here on this thread don’t know if their unit is running up to its capabilities, they think a clean filter and coil is all there is to it. Yours may or may not be. I have many customers who have 30+ year old units still working great others have problems and aren’t worth fixing.

Lack of maintenance causes most problems but there is more to it than cleaning the outdoor coil and the drain.

As an example I was doing a maintenance call last summer and put my digital gauges on the system and saw an unusually low pressure, (the suction line was cold and sweating so most people would think the unit was running properly) but when I measured the line temperature it was much colder than it should have been indicating an airflow problem. I checked the indoor coil and there was a piece if insulation that came off of his ductwork that was blocking half the airflow across his indoor coil. Took a couple of minutes and no parts to fix.

My point is have a good honest evaluation done, and look at your options, don’t take the advice from home owners who have no idea how the system really works.
tomd37
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Re: What to do with 26 year old central AC unit?

Post by tomd37 »

Designairohio - Well said and good advice in my opinion!
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illumination
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Re: What to do with 26 year old central AC unit?

Post by illumination »

ragnathor wrote: Wed Mar 31, 2021 8:18 pm This post has been quite useful. I was debating whether to get annual checkups but now I won't.

Any tips on knowing a competent/honest tech from one who's not for someone HVAC illiterate? I had a reputable company come 6 months ago and charge 200 repair and 600 for Freon (claimed they tightened some expansion valve). Same problem recurred with near empty Freon - gave me another 800 estimate to refill and diagnose with a dye test, and repair would be unknown additional amount.

I had another guy come, found leaking copper tubing which he fixed and replaced the Freon for 500 total.
This is the sort of stuff I'm talking about. And despite what AC techs tells you, R22 is easily available and costs them around $17 a pound. A typical heat pump from EMPTY is 6-12 pounds. So a completely empty unit should only require about $200 worth of R22 refrigerant. Most of the time, a unit blowing cool but not cold just needs like 1-2 lbs. I bought my own tank when they started that scam of "$100 a pound plus a service charge".

Unless your AC is not blowing cold air, leave it be. You can stick like a meat thermometer in your register, if you're getting around 55-60 degrees blowing out on the closest register to the unit, you're probably fine. Or take the temp before and after the unit and look for a 15-20 degree difference. Just a rule of thumb, not a technical spec.
A440
Posts: 678
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Location: NJ

Re: What to do with 26 year old central AC unit?

Post by A440 »

livesoft wrote: Wed Mar 31, 2021 9:25 am We have 2 complete central AC systems: one for the upstairs and one for the downstairs. They are 28 years old. We do not do annual maintenance and never have. We only have them fixed when they break which is simple stuff like a relay or a capacitor except for the time when lightning "blew up" an outdoor unit leaving the one next to it completely undamaged.

Your assumption about replacing just because it stops blowing cold air is a false one. For instance, a repair part costing less than $50 could be the problem and easily fix that.

And we have NEVER had the "fins" cleaned though we keep vines from growing up and around the outdoor units.
Sounds like our home and what we do. YouTube when something breaks, or come here for help.
I don't know what the future holds, but I know who holds my future.
skis4hire
Posts: 23
Joined: Thu Oct 11, 2018 12:54 am

Re: What to do with 26 year old central AC unit?

Post by skis4hire »

Anyone with a 30 year old AC unit should start researching heat-pumps.

Modern heat pumps can both heat and cool your house, replacing your furnace, and work efficiently down to very cold temperatures (-10F or less) with backup options for extreme events below that. They work with forced air or radiator systems and can also integrate into your hot water heater in some cases.
The outdoor portion of modern units are also much quieter than most legacy AC units.

Many locations have significant rebates for heat-pump installations as well.
Target2019
Posts: 517
Joined: Sat Mar 03, 2007 5:30 pm

Re: What to do with 26 year old central AC unit?

Post by Target2019 »

harrington wrote: Wed Mar 31, 2021 6:33 pm
pb1996 wrote: Wed Mar 31, 2021 9:21 am 26 year old central AC. Working well. I had been paying for annual "routine maintenance", they seem to just charge me $150 to document everything is in good working order. It doesn't appear they do any "tuning up" or anything.
Should I stop having these annual checks and just wait for it to stop blowing cold air before I call someone in? (I'm assuming at that point a new unit is in order...)

Thanks!

Pb
I worked in heating and cooling and I can honestly tell you these annual checkups are nothing more than a money grab. Call them when they don’t work. It was a joke in the industry that they clang a few pipes, shine a flashlight around and turn a vacuum on :D
I had two ancient systems replaced. The furnaces were 40 years old. The new equipment came with a 2-year service (2x's a year) schedule as part of the installation. I watched the young fella do his magic, which was not much. Flashlight and vacuum were impressive. He also measured the output with a nifty wand.

When two years were up the company sent me a $400 invoice to renew service for one year. They followed up with phone calls and emails. At one point I had to let the sales guy know it was too much. They still call and send invoices.
tibbitts
Posts: 13348
Joined: Tue Feb 27, 2007 6:50 pm

Re: What to do with 26 year old central AC unit?

Post by tibbitts »

wfrobinette wrote: Wed Mar 31, 2021 1:59 pm
Polymorphic wrote: Wed Mar 31, 2021 9:26 am The company that does my annual tuneup will clean the condenser unit fins with a hose, which keeps it operating efficiently. You can do this yourself (just pull the power first!) if your time isn't worth more than the service call.
Why would one need to pull the power first?
Typically the tech will remove the shrouds and grates surrounding the unit, and possibly at least move the fan, so the unit turning on would cause the fan blades to be... dangerous, definitely to themselves and maybe to you.
Broken Man 1999
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Location: West coast of Florida, inland on high ground!

Re: What to do with 26 year old central AC unit?

Post by Broken Man 1999 »

I don't think DW is going to be crawling around in the attic to periodically inspect the heat pump unit for upstairs. So, for us, maintenance inspections are a no brainer.

When I replaced the downstairs heat pump earlier this year, I had a 6 month filter installed to replace the filter location in the ceiling for the upstairs unit.

Seemed foolish to have DW getting on a ladder to replace the filter each month. She has new knees, but a bum hip.

I consider the costs of a maintenance inspections much like I consider the cost of AAA membership. The sum is insignificant, but the risk to DW significant should she fall.

We replaced a 17 year old heat pump, over the years we had a couple of service calls to fix. If we hadn't had a visit for maintenance, our guy just deducted the cost for one of the maintenance inspections from the repair bill. Helped us, helped him, as no extra trip needed, he just repaired the unit, and checked everything out on both units.

Decent guy. We met him when he was an employee of the company, now he is the owner of the company. Still a small company, we still know everyone. Used the company many years. We tend to stay with our trades people, once we have found one we trust. I never begrudge paying for good service, so long as we receive it. Not every trades person is out to rip people off. The trick is to vett them carefully and treat them well.

Broken Man 1999
“If I cannot drink Bourbon and smoke cigars in Heaven then I shall not go." - Mark Twain
raixx017
Posts: 74
Joined: Wed Feb 28, 2018 5:41 pm

Re: What to do with 26 year old central AC unit?

Post by raixx017 »

Many great quotes in this reply from Watty, but this one is the key.
Watty wrote: Wed Mar 31, 2021 11:36 am
If you live in an area where it would be a real hardship to go a week without AC in the summer then I would look at getting bids to preemptively replacing it to see if you can get a good price.

The problem is that if you wait until it fails on a 90+ degree day in August then you will get a real high price, if you can even get someone out to install it in a reasonable amount of time. I once had to replace a failed water heater where I had to pay a premium price to get done because I had few other options.

It will vary with your local climate but there is usually a gap in the spring and fall between the heating and cooling season when HVAC companies are not very busy.

I would say, if you are comfortable to start and complete the process of replacing a broken old hvac system when it dies during peak summer time, then you don't need to do much right now. In this case, you may be charged a premium, the HVAC equipment/technician availability may be limited, and you may have to spend some time in a hotel. These may be just "manageable inconveniences" to some, or nightmare to others...so this is very subjective.

There's no harm in getting the quotes well ahead in time, so that you at least know how much you may have to _eventually_ shell out.

FWIW, I was in a similar boat, and I decided to go ahead with replacing my system in spring.

Regarding, "annual maintenance"...as others have pointed out, it is not just cleaning the condensing coils and changing filters. In the least, you should also flush your drain pipe. I know someone who does this on his own, while others (like me) hire people to do this. But please don't ignore cleaning that drain pipe. Other things that a "proper" maintenance guy would do - check capacitors, check freon level (by hooking up gauges), check for wear of parts (my guy caught a cracked condenser fan, which I overlooked). So, if you get the right person it can be useful. However, there are a few minimum things that can be done on your own.
Last edited by raixx017 on Wed Apr 07, 2021 11:49 am, edited 2 times in total.
rotorhead
Posts: 534
Joined: Wed Mar 17, 2010 3:59 pm
Location: Florida

Re: What to do with 26 year old central AC unit?

Post by rotorhead »

Re: What to do with 26 year old central AC unit?
Post by carolinaman » Wed Mar 31, 2021 11:31 am

I pay $195 annually for twice a year service, once for gas heat and other for AC. The guy I use is a one man company recommended by my son who uses him for businesses, condos and homes he maintains. He is very practical and will never recommend something that does not need to be done, unlike these big companies that advertise on TV and have commission based techs. Also, this guy is very responsive when I call him.

I am not as handy as some of you and find this a reasonable service. If not comfortable servicing these units yourself, IMO you need to have a relationship with a company you trust and that will promptly respond to your needs.
I am in this camp as well. I grew up in an era where we did things like this for ourselves (especially auto maintenance); but as I've aged, my fingers are not as nimble as they used to be - and my motivation has declined appreciably. So I'm happy to have service call twice a year to check and service these things.

Thanks to successful "Boglehead" investing, I can afford it. :happy
dogperson
Posts: 43
Joined: Wed Feb 28, 2018 10:36 pm

Re: What to do with 26 year old central AC unit?

Post by dogperson »

OP has disappeared, but...

Do you also have heat? My HVAC company does maintenance on both units at each twice-yearly visit. Being on the maintenance plan also gets me priority response with no service call fee when something breaks, which is usually the heat in winter. Since I have gas heat, maintenance is also a safety issue.

I'm frugal on a lot of things, but not on the things that keep my house in good shape.
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