Best home HVAC systems and DIY?

[A930Rocket]

A couple of months ago, our AC was not working at home. I replaced the compressor motor and capacitor. Then replaced the air handler motor and capacitor. The AC worked well.

For the past week, it’s not working as it should. The compressor and air handler are working. With two different infrared thermometers, I’m getting 66° out of the vents, but the house is not getting cooler.

When I hold my hand up to the vents, I can barely feel the cold air coming out. I’ve ordered an anemometer, to help me determine CFM. Looking online, a rule of thumb is to multiply 400 by the tons, to get CFM. In my case, it should be 400 x 2.5 = 1,000. Maybe this will tell me if the air handler blower motor is deficient.

I had a guy come out and he said the Freon level and pressures were good, but that my compressor condenser fins were worn out, falling apart and clogging the airflow. In several places, the aluminum fins were turning to dust. it’s not losing the heat as it should. It’s a 13-year-old carrier system.

He’s going to let me know what it would cost to replace the compressor/condensor and evaporator at the air handler, but he said it’s probably in the $6-7k range.

I had gotten a price a couple months ago from the HVAC company I use at work for $7k. With my choice of Lennox, Carrier, or Trane.

What are your experiences with the three choices above?

On another note, the amount of money I saved by replacing the electrical motors and capacitors myself was significant. It made me wonder if I could replace the compressor/condenser and evaporator at the air handler myself, then have somebody else evacuate it, pressure test it, and fill it with Freon. I think I can do it, but looking online, the only make I could find was Goodman. It seems they will sell to anybody, but have a bad reputation. Of course, then I would have to wonder about any kind of warranty.

[Roswell]

My order of preference would be Trane, Lennox, Carrier.

I have owned both Trane and Lennox, and am familiar with Carrier through friends' experience with the brand.

With the newer units, proper installation is critical.

[billybek]

I would add York to that list and put it at the front of the line.
Their lower line is Coleman. The last two splits I had installed for friends were Yorks.

I installed a Trane split at my house many years ago and it is still running.

[WSH]

How are the new "Inverter" systems (slim outdoor unit, variable speed fan etc)
I believe Amana and Daiken are key brands ?

[NY65912]

Check out the DIY HVAC guy on YT. He has tons of really good videos on brands and diy installations.

https://youtu.be/1QlC1NsA-GY?si=6xBubLnm48bOdbie

[A930Rocket]

I checked the airflow with my anemometer and came up with the calculations below.

CFM = Velocity x Area

If I use the standard 400 x 2.5 tons, I should be measuring 1000 CFM at the vent.

My calculations are coming in at 168 CFM, which seems very low, for a brand new blower motor.

[Alan A]

Shouldn’t you be measuring it just after the fan? I mean it doesn’t feed just that vent.

[A930Rocket]

Good question. From what I had seen online, people were measuring at the vent

[A930Rocket]

I was talking to my HVAC guy and he gave me the option of the Trane system that uses the new refrigerant or American Standard, that uses the older refrigerant.

The Trane system has more safety checks, because the gas is slightly flammable and when it detects the gas/leak, it shuts down, and it has to be repaired versus the American Standard with the old refrigerant, where it might be topped off.


Soooo…. Would you go with the Trane and the new refrigerant or the American Standard and the old refrigerant? Pros and cons?

[Baz]

Originally Posted by A930Rocket

the only make I could find was Goodman. It seems they will sell to anybody, but have a bad reputation. Of course, then I would have to wonder about any kind of warranty.

As a Data point, I had a Goodman R-22 condenser unit dropped shipped here 12 years ago that I bought online - I think the company was in Houston. Also got an inline filter drier with it. Was able to hire a guy to do the change out who moonlighted on weekends from his full time job with a local HVAC company. It only took about an hour and wasn't a big deal for him and easily worth some cash I paid him. The condenser unit delivered was approx. $1K. Did not contain any refrigerant, per Federal law.

That Goodman hasn't missed a beat since day 1. I do clean the fins every couple of years and sprayed some corrosion protectent on the filter drier but that's it.

In Post #5...Mike mentions the HVC DIY guy on YT. If you haven't yet - I recommend to go through as many of his videos first before making any decisions. He's very knowledgeable and I found his videos very helpful for my HVAC needs.

Originally Posted by A930Rocket

Soooo…. Would you go with the Trane and the new refrigerant or the American Standard and the old refrigerant? Pros and cons?

That question might be answered in one of the videos by the YT guy I referenced above.

One more item that might be of interest. Quite a few years ago, I decided to install a window unit in my living room to take some of the "load" off my central AC. I didn't have to do it. It was a concept I came up with that I thought might extend the life of my central system. I only use it during the warm season here. I have it set at 73 and ECO-mode. I think it's only a 5-6K BTU unit. Almost runs continuously since I leave my main system thermostat set higher. For what these window units cost - I'd rather replace one of those than the main system, push come to shove.

I can also use it along with my portable generator during power outages (hurricane season). I have another brand new in box and a larger one also in it's box that's 12K BTU's. Just in case.

My house isn't large (2 bed/2bth) and only 1 story so not too hard to moderate but it is Florida so still crucial to have it (or something) working right.

I also have a small bottle of R-22 on hand in case I need to top it off one day.

One day I may have to upgrade - maybe a mini-split. We'll see.....

Pics of my Goodman.....

[A930Rocket]

3-4 years ago, I bought a Whynter portable air conditioner, that is freestanding, with an intake and exhaust at the window. During the summer, I use it in the owners bedroom and close the doors. This week, I’m not trying to cool the entire house.

Unfortunately, I just started using it and it’s not cooling either. I’m going to open it up and see if they’re any DIY parts I can service.

[Zeke]

At my age I'd probably buy a Goodman. I have a package unit on the roof so it's just a matter of craning it up there and doing some duct work in case the match up it's right. With the kind of money HVAC people want nowadays I'll take what might be called an inferior product.

I would up-buy if other companies would get their heads out of their ass and sell direct. I think the mini split business is going to hurt the residential segment of many of the top brands' products.

That don't bother me one iota.

[frosty2]

The register you show would be considered a 6x10 supply register and at your face velocity of 492 is supplying just under 100 cfm which is designed proper as they should be around 500 typically for residential for sound reasons. It is likely fed with a 6” perimeter pipe so you should see how many you have in the house and total all of them.

[Baz]

Originally Posted by Zeke

At my age I'd probably buy a Goodman.

A name you can trust!

[Brian 162]

Originally Posted by A930Rocket

I was talking to my HVAC guy and he gave me the option of the Trane system that uses the new refrigerant or American Standard, that uses the older refrigerant.

The Trane system has more safety checks, because the gas is slightly flammable and when it detects the gas/leak, it shuts down, and it has to be repaired versus the American Standard with the old refrigerant, where it might be topped off.


Soooo…. Would you go with the Trane and the new refrigerant or the American Standard and the old refrigerant? Pros and cons?

Go with the old refrigerant. I was in HVAC and retired 12 years ago. I still speak to my friends that are still in the trade. They don’t speak highly of the new refrigerant/ units.
410 is still readily available.

[A930Rocket]

^^^ That was one of my concerns, about the availability and cost of the older refrigerant. I didn’t want to use something that was unobtainable or crazy expensive.

[A930Rocket]

Originally Posted by frosty2

The register you show would be considered a 6x10 supply register and at your face velocity of 492 is supplying just under 100 cfm which is designed proper as they should be around 500 typically for residential for sound reasons. It is likely fed with a 6” perimeter pipe so you should see how many you have in the house and total all of them.

I’ll take a look tomorrow and count.

If the velocity is correct and I’m seeing 66° with my infrared thermometer at the grill, why isn’t the house cooling?

[frosty2]

Typically you should see temperatures around 60 degrees coming out of your registers, depending on the temperature in the house at the time.
Your mechanic likely checked this but if you want to see if your system is running properly you need to drill a small hole in your ductwork before and after your evaporator coil. Insert a probe style thermometer and measure the temperatures there.
What you want is a temperature difference of 15 to 20 degrees. Less than that and your system is either low on refrigerant, has a dirty air filter or dirty or plugged condenser.
Maybe Brian can chime in on this as well.
Also when choosing a new Brad it’s nice to choose one that a local installer carries and is familiar with just for future service and available parts.

[A930Rocket]

Thanks everyone. I decided to go with the Trane, as everyone recommended it. Guys are here now installing everything. I know the owner of the company and he’s worked with us, for 25 years. They brought a lot of stuff down from the attic, but maybe the heat part.

[Baz]

Good choice, A930!

"Nothing stops a Trane!"