Get New HVAC or Keep Old?

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Background: HVAC is 20 years old. Working fine, never had a problem, elec bills extremely reasonable. However, If it were to go out now during long weekend holiday we'd be up the creek. Two old folks, 3 dogs, 1 cat. No motel would take us, no one to take us in. Not sure we could stand the heat. Don't know of any repairmen that make weekend calls. We expect to live here as long as possible.

Am thinking perhaps I should get ahead of the potential problem and have new HVAC installed.

Yes or no?.
 
Some motels allow pets,

Simple solution: Buy a window unit as an emergency backup. And a generator to run it.

Edit to add: Be wary of HVAC dealers, they are just as bad as car dealers.
 
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As a pro refrigeration tech (& occasional A/C guy for friends & relatives), you're getting up there in age for compressor lifespan. not to mention coil life. How does the outside unit look? Are you keeping it as clean as possible, giving it a good bath & washdown AT LEAST once a year (I recommend in the spring when first starting it)? Do you change your furnace filters regularly? Does the compressor sound good when it is running (smooth, even growl, no banging on start up/shutoff)? I have heard too many stories of shady operators in the A/C business, almost ALL companies pay a spiff (bonus or bounty) to their techs to sell new systems, AND pressure them to sell a certain amount of systems-or they're gone! This is why, much like auto repair, why people need a good relationship with a trustworthy service guy to avoid getting ripped off.
 
Id say No. What you need is a temporary backup solution. Go and buy a large window A/C or portable A/C unit. 300$...and if ever it goes kaput, you bring out the portable unit to keep one of your rooms cool, until a repair can be done. Issues with HVAC can happen on new systems also, this way..even if u replace it with a new HVAC down the road, you have backup. Thats what id suggest.
 
There's more to it than cheap utilities.

If your well off and want the most comfort possible, you'd get a variable speed AC with a matching furnace or air handler.
You can blow the humidity out of your house running the AC at 78 degrees on a hot day while you'd need to set it lower with a single stage system.
Two stage AC works well if it can be sized correctly for the size of your house.
As people age, women especially, they tend to want to tick the thermostat up higher.

if you can afford the toys in your signature, you should consider spending a few bucks for your wifes comfort and yours, too.
 
Smaller portable floor units are available. Heat and moisture are rejected through a flexible duct through a fitting placed in an open window.
 
Have you maintained the system properly?
Washing the outside coil every year or even 2x a year.
Check the capacitor every year and replace as necessary.
Make sure the condensation line is not blocked from the evaporator (may be in the attic).
HVAC tech can check the refrigerant pressure and the amperage usage during starting to see the health of the system (DIY if you have the tool).
etc...

A lot of AC issue happens when capacitor went out.
It is not a bad idea to check what capacitor is used in the unit and have spare at home at least 1 for each type or get one of those multi capacitance capacitor.
A unit will have at least 1 or 2 running capacitor and 1 starting capacitor.

Here in DFW area, there are a lot of HVAC company that will come on the weekend.
I have a friend that I met at my daughter's school that do HVAC and he is in my phone book.
Last time, I called him on Sat night and he came on Sunday morning.
 
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I live 20 miles from you and their are plenty of HVAC people in our area who do emergency calls all the time. They even advertise as such on their work vans. My 24 year old Trane is happily humming away but if it poops out in the next hour I feel confident I can get someone out here today to fix it, granted at a premium on a holiday. I had a new furnace installed last fall and the tech checked my ac unit and said " they don't make them like this anymore" and it would be worth repairing when the time comes, though it does take more energy to run. As an aside, do you still have that IBM 30 cal carbine?
 
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20 year old unit has a seer factor ( efficiency) of 10 at best. New systems at a minimum have 13. Compare nameplate amperage both compressor and fan fan motor and compare it with new equipment. For under $200 can buy a 5k to 8k window unit for emergency and piece of mind it will keep a bedroom cool and can always put a box fan in the doorway and blow air into the rest of the house to take the edge off.
 
Originally Posted by MrMoody
Buy a window unit as an emergency backup.


Or a portable unit for the bedroom. A/C units made 20 years ago are much better built than the new ones with Chinese compressors and other parts. If yours runs on R22 I'd pick up a drum of it off Craigslist in case you get a leak. 29 year old HVAC in my house works fine and I heard some people still have the original units from houses built in the 70's. As long as parts are available, even universal ones, it can be kept working a long time.
 
Depends on how handy you are. An old unit can nickle and dime you but if you are handy at DIY repairs, some things can be fixed a few dozens of dollars at a time instead of hundreds at a time.

For example once my parents had their motor start/run capacitor fail and they called out a repairman. He charged around $250. That capacitor lasted only 14 months and they had me take a look at it. I got the same cap (had reservations about doing that after the 1st had such a short lifespan but it was the only brand that supplier had, it was summer and they're older) for $13 and it took 5 minutes to install.

Then again, it's a matter of how long you can tolerate the system being out. If that will cause much distress I would go ahead and replace it instead of paying even more for a window unit... buying the window unit probably isn't going to make it last much longer so it's just more expense.

Keep in mind that while many advise that you should replace the furnace and A/C at the same time, in many situations there is no real reason why you need to. A higher efficiency unit may have a larger A-coil but if it still fits in your furnace stack, it's compatible. Granted if the furnace is also 20 years old it may not have a long life ahead of it either, but again you gamble how long you can DIY repairs at what cost per yer vs inconvenience if it fails. Personally I find it easier to find alternate sources of heat than cooling, portable heaters are only $20 and there's stove burners or oven, fireplace, etc.
 
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Originally Posted by JMJNet
Check the capacitor every year and replace as necessary.
A lot of AC issue happens when capacitor went out.
It is not a bad idea to check what capacitor is used in the unit and have spare at home at least 1 for each type or get one of those multi capacitance capacitor.
A unit will have at least 1 or 2 running capacitor and 1 starting capacitor.

As long as we're on this topic, how do you manage capacitors in HVAC units? What do you look for, and when do you replace them?

My unit is 34 years old... original furnace and a/c. The a/c isn't used much here in Michigan. It'll likely die from corrosion before it wears out.
 
Originally Posted by Kestas
As long as we're on this topic, how do you manage capacitors in HVAC units? What do you look for, and when do you replace them?

Look for capacitors starting to bulge or already bulging.
 
Originally Posted by gman2304
I had a new furnace installed last fall and the tech checked my ac unit and said " they don't make them like this anymore" and it would be worth repairing when the time comes, though it does take more energy to run.

An honest company like this deserves to be named publicly.

DO NOT let just anyone come to your house for a quote or inspection. A few are not above sabotaging your system (slow leak etc) to get a sale.
 
Keep running it. If it is an r22 system you could add two teaspoons of mineral oil to keep it going longer. You will need gauges and r22 tank to do this. Did this to my daughter unit in NC, unit was 30 years old and still running when she sold the house.
 
Originally Posted by Kestas
Originally Posted by JMJNet
Check the capacitor every year and replace as necessary.
A lot of AC issue happens when capacitor went out.
It is not a bad idea to check what capacitor is used in the unit and have spare at home at least 1 for each type or get one of those multi capacitance capacitor.
A unit will have at least 1 or 2 running capacitor and 1 starting capacitor.

As long as we're on this topic, how do you manage capacitors in HVAC units? What do you look for, and when do you replace them?

My unit is 34 years old... original furnace and a/c. The a/c isn't used much here in Michigan. It'll likely die from corrosion before it wears out.


I bought a cheap capacitance tester (ONLY) from Amazon/Ebay that have a higher measurement range or you can get a more expensive multimeter with a higher range capacitance tester.

Every year, when I took off the winter covering, I tested all the capacitor.
For the most part it is good, you can see it bulging when it goes bad but 2 years ago I found a capacitor that is not bulging yet but it only has 2uF well below the rated 10uF.
It was an Amrad capacitor with 5 years warranty so I sent an email to them and they sent me a new one for free with a return label to return the defective one.
In TX, we used the AC more than the heater.
The AC coil cover usually goes up in late November/ early December and taken off sometimes in mid March.

Note: be careful when testing capacitor when the unit has been turn on.
Check Youtube and they have lots of video on this.

Based on experience, even in MI, you may want to turn the AC unit on sometimes to preserve the unit.
AC will go bad if you never turn it on.
 
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Originally Posted by Kestas
Originally Posted by JMJNet
Check the capacitor every year and replace as necessary.
A lot of AC issue happens when capacitor went out.
It is not a bad idea to check what capacitor is used in the unit and have spare at home at least 1 for each type or get one of those multi capacitance capacitor.
A unit will have at least 1 or 2 running capacitor and 1 starting capacitor.

As long as we're on this topic, how do you manage capacitors in HVAC units? What do you look for, and when do you replace them?

My unit is 34 years old... original furnace and a/c. The a/c isn't used much here in Michigan. It'll likely die from corrosion before it wears out.


Capacitors are a crapshoot. I mentioned a replacement that lasted only 14 months, then replacing that with the exact same thing lasted over 3 years before the whole unit was replaced.

Few people replace them preemptively, instead waiting for failure. When they fail they fail fast, will bulge on the end instead of being flat. It is a great idea to have a spare already if your unit is getting older.

The failure is pretty obvious when it happens, the motor starts making funny sounds instead of spinning, but the one I repaired was in an area right next to a garage and frequently used entrance door so the owner was in and out often enough to notice that.

Anyway the motor could have shot bearings/bushings instead but if you (shut off power to it first) and can spin the blades without resistance, it's probably not the motor. Windings could short out but that would usually trip a fuse and regardless the capacitors don't usually last as long as the motors so checking the cap first gets to the most likely problem the fastest.

Lastly, "lubed for life" fan bushings is nonsense. It just means the fan will fail if the bushing runs out of lube and will last MUCH longer if you use a very light oil to lube every few years. Once upon a time ago they used to have lube ports, even tubes going to the ports to squirt some oil in, but in recent decades they saved 20 cents by omitting those so it takes more labor to get to the bushings to lube them. On older units then often have a felt/other reservoir so you can get quite a bit of oil into them but make sure you don't over-oil to the point where it's pushed out into the rest of the motor.
 
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My furnace and AC vintage 1982 and they still work well. Compared to my neighbor who has new AC and furnace I spend $300 - $350 more per year. Doing the math it makes no sense to replace them. I do have back up heat [gas fireplace]. When it comes to sell the house I'll probably replace them as people don't appreciate the old reliable equipment.
 
A spare dual run capacitor & a 24V contactor are good spare parts to have on hand, if you're mechanically inclined enough to replace them. Capacitors don't generally fail yearly, unless you have really high voltage or Chinesium caps!
 
Originally Posted by gman2304
I live 20 miles from you and their are plenty of HVAC people in our area who do emergency calls all the time. They even advertise as such on their work vans. My 24 year old Trane is happily humming away but if it poops out in the next hour I feel confident I can get someone out here today to fix it, granted at a premium on a holiday. I had a new furnace installed last fall and the tech checked my ac unit and said " they don't make them like this anymore" and it would be worth repairing when the time comes, though it does take more energy to run. As an aside, do you still have that IBM 30 cal carbine?


Thanks for info. I do still have the IBM.....Have we met before?
 
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