DIY HVAC

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Jul 30, 2003
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Anybody done a self replacement of an old ac/heating system?

This is one of those things at first I was like no way, but I also thought that about replacing engines, car a/c systems, installing Linux, etc at one time and LOOK AT ME NOW!

Anyway... and I'm not talking about those modular things. I'm talking about the old school 'central' heat and air systems. Outside fan and compressor, inside handler, blower, condenser, whatever.
 
I am all for being a DIY'er but if you don't have the expertise and equipment to do the job, I would leave it to a professional. Having equipment installed and sized in a proper manner is more important than the equipment itself.
 
Never done it, but my buddy bought refrigerant at an autoparts place when he did his as you can get 1lb bottles instead of the 20lb ones at the HVAC suppliers. I imagine there must be a youtube clip showing how its done, there's probably a few big mistakes to avoid and the rest is simple enough on a straight replacement.
 
Never done it, but my buddy bought refrigerant at an autoparts place when he did his as you can get 1lb bottles instead of the 20lb ones at the HVAC suppliers. I imagine there must be a youtube clip showing how its done, there's probably a few big mistakes to avoid and the rest is simple enough on a straight replacement.
Which HVAC refrigerant was purchased at an auto parts store?
 
As an HVAC tech I'm not saying you cant do it yourself but there are some key details and tools needed. If you dont have the tools or know how to set the refrigerant charge its going to be an issue.

Also brazing in line sets is not really diy friendly.
 
Anybody done a self replacement of an old ac/heating system?

This is one of those things at first I was like no way, but I also thought that about replacing engines, car a/c systems, installing Linux, etc at one time and LOOK AT ME NOW!

Anyway... and I'm not talking about those modular things. I'm talking about the old school 'central' heat and air systems. Outside fan and compressor, inside handler, blower, condenser, whatever.
If you understand how to solder dissimilar metals (Aluminum w/Copper) and have the necessary equipment you could do it. You problem will be evacuating the system. Of course I haven't included the tools to build the plenum, filter box, condensate pipe, etc.

It's not a DIY.
 
I am all for being a DIY'er but if you don't have the expertise and equipment to do the job, I would leave it to a professional. Having equipment installed and sized in a proper manner is more important than the equipment itself.
Yes.

Many people think bigger is better in this situation and that just isn’t the case. Better to let a smaller unit run than to have a big unit cycle on and off constantly.

You also have to make sure the system adequate flow. Enough supply and returns, correct duct sizing etc.
 
Another thing to keep in mind, if newer windows, doors and insulation were installed after the original system was installed, the new system likely will need to be smaller than the original system.
 
As an HVAC tech I'm not saying you cant do it yourself but there are some key details and tools needed. If you dont have the tools or know how to set the refrigerant charge its going to be an issue.

Also brazing in line sets is not really diy friendly.
Don’t you also need a EPA Section 608 certification to buy the refrigerant?
 
If it's just a replacement I don't see why most people here couldn't at least buy most or all of the parts and at least mount the stuff themselves.

I know that I could easily remove my old stuff, pour a concrete pad for a new compressor and mount the compressor, and have the new air handler and coil ready for an actual professional to complete the install.
 
If it's just a replacement I don't see why most people here couldn't at least buy most or all of the parts and at least mount the stuff themselves.

I know that I could easily remove my old stuff, pour a concrete pad for a new compressor and mount the compressor, and have the new air handler and coil ready for an actual professional to complete the install.
I don’t know any legit HVAC people who will do this because most of the time the warranty is void unless it’s purchased from a supply house (I think Goodman is one of the few who will sell directly to consumers) and installed by a licensed person. Also, even if you could keep the parts warranty intact, no one wants to be doing “warranty labor” repairs for free because someone ordered equipment on Amazon and UPS decided to drop kick it several times during shipping. This goes for both owner provided systems and even just parts.

You may be able to find some dude with equipment who will do it but buyer beware. This topic comes up frequently and most HVAC people won’t do it.
 
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You need to right equipment. If the system you are replacing is R-22 then you'll need to capture that.
You'll need a vacuum pump, a set of gauges, know how to braze etc.
With enough research, the right tools and the certifications (if required) for the refrigerant, I don't see why anyone above average mechanically inclined couldn't to this.

Most of the HVAC techs that come out to your house aren't working their way through med school.
 
I don’t know any legit HVAC people who will do this because most of the time the warranty is void unless it’s purchased and installed by a licensed person. Also, even if you could keep the parts warranty intact, no one wants to be doing “warranty labor” repairs for free because someone ordered equipment on Amazon and UPS decided to drop kick it several times during shipping. This goes for both owner provided systems and even just parts.

You may be able to find some dude with equipment who will do it but buyer beware. This topic comes up frequently and most HVAC people won’t do it.

Yeah, no warranty and find someone off Craigslist to finish the job. So what. The warranties are mostly worthless anyway. I have only known one person to ever use it, and they got ripped off just the same because the warranty only covered parts and there was a minimum charge by the HVAC people that turned a sub $100 repair that I could have DIY'ed into something that cost several hundred dollars.
 
Yeah, no warranty and find someone off Craigslist to finish the job. So what. The warranties are mostly worthless anyway. I have only known one person to ever use it, and they got ripped off just the same because the warranty only covered parts and there was a minimum charge by the HVAC people that turned a sub $100 repair that I could have DIY'ed into something that cost several hundred dollars.
Labor warranties are typically 1-2 years but some offer longer. If it's a risk you're willing to take...there are also TONS of hacks in HVAC who can do more damage than good.
 
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Labor warranties are typically 1-2 years but some offer longer. If it's a risk you're willing to take...there are also TONS of hacks in HVAC who can do more damage than good.
I just got a quote for 10 years parts and labor over a quote for 10 years parts and 1 year labor.
The difference was $5500.
And if you buy junk it probably will be ready to be replaced in 10 yrs.
 
What looks like a simple evacuation process includes removal of contaminates from the refrigerant line. Nitrogen, oils, wee bits and moisture will foul new equipment in a matter of months.

You're good but you're likely not that good.
 
By rights need a epa refrigerant licence to handle the refrigerant. Don't know who would warrantee the equipment. Know how to wire the controls and power wiring. Most importantly running a new line set or flushing the old line set and charging the system. The old r22 was very forgiving compared to r410a.
 
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