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lkabug

lkabug

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My 14 year old HVAC system has bit the dust. I'm now looking at two new systems. My question is which is better, one with 2 stage compressor but not variable speed blower or.... single stage compressor with variable speed blower? Both units about same price point installed.
 
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I read a couple HVAC "forums" on Facebook,, basically pro installers talking about their life,,

From what I gather there,, the manufacturer is the most important aspect of a system, not a feature.
 
The quality of the installation is at least as important as the equipment. I have a simple single stage compressor with a variable speed blower. Installed last year, it's quite a bit more efficient than the old one. My electric bills show the difference.

Even during these last two weeks of 105-112 daily highs the new unit has kept my home cool and comfy while neighbors complain that their systems can't keep up. My new one is American Standard (Trane), for whatever that's worth. My previous Rheem system lasted 18 years.
 
I’ve been in the trade for 30 years and have seen more than my share of butchered installs by the “low ball bid “ crowd. The installation is THE MOST IMPORTANT part of the equation. More than 75% of systems are installed incorrectly, shortening the life of the system.
A reputable contractor is paramount to getting a properly installed system.
Single stage compressor with a variable speed blower is a nice easy to work on combination.
 
Consider an air heat pump and a high efficiency back up furnace. We had a Trane system installed about 11 years ago and the energy savings (electric/gas) just about paid for everything.

My AC unit was 19 years old and quit working on a hot day when the in-laws were visiting. A Trane dealer who belongs to my gun club got it running that day, but he told me it was on its last legs. He also looked at our furnace (a low efficiency spec furnace that was the same age) and suggested the system upgrade. It was one of the best improvements we ever made.

The heat pump is connected to interruptible service, which provides a discount on electric. It works as an AC unit, but also provides heat when the outside temp is above 40 degrees. The interruptible discount is higher in the winter, when no one is running their AC. The system just about slashed our gas/electric bills in half during peak months.
 
Thanks to all for your advice.
Decided to go with a Trane HVAC, hybrid system, heat pump/LP furnace and 2 speed compressor and variable blower. 16.2 SEER2.
Hopefully, this will be my last.
 
These fancy new HVAC systems are all very well, but when being fitted to an existing home I suspect the hoped for efficiency is compromised by the existing duct layout and the re-use of existing pipes made for R-22 and not the new refrigerants. It will still be better than the old gear, but not by as much as expected.
 
Yes, as stated, installation is THE most important part. Of course, equipment brand is important. Some lowball prices are for construction grade equipment (cheap). Trane is a very good brand. (I put a Trane furnace in after I moved in, 2004, and not one issue.) Also, you're getting a top line system, so I would strongly suggest you use the same company to to perform the preseason maintenance checks. There are circuit boards and other high tech gizmos in there, and I would assume that company can service what they sell. I've spent my HVACR career in the commercial/industrial side of the business but have had to work on residential-sized stuff. Plus favors for a couple relatives. I'd be lost on this new inverter drive compressors, but I know my system will need replaced soon, especially the A/C side. I will pay some contractor when/if I need it. I also will insist on all new line set, even if I have to put it in myself. But from what I've seen & heard they do that anyhow. Like LVSteve wrote, the ductwork/air distribution system is very important. Hopefully the salesperson took that into consideration. Although, unless you're on a one story home with basement, you're stuck with what you got.
Good luck, and let us old retired mechanics & service techs know how you like it! FWIW, I, too, will go with a Trane when the time comes.
 
I’ve had my Trane inverter straight cool system in since 2014. No issues.
 
As far as equipment goes, I have had 2 speed compressors die
after 2 years of service. I like the theory. Application is still
lacking.
I have not seen a variable speed fan motor that I would trust to
not fail early. The technology simply hasn't been refined yet.

For Virginia, get a good 2 stage heat pump. The compressor has
extra durability to last longer for A/C and heating. variable speed fans don't save wattage to speak of and WILL fail.
Equipment will be a little more expensive to install, but will pay
for itself.
I've had good experience with Lennox, Carrier, and ArcoAire here.

I have not trusted Trane equipment for years.
Many reasons why. All have to do with durability. YMMV.
 
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My life's experience has mostly been, simpler is better in the long run. Whenever I've had automatic variable speed motors / pumps I've experienced premature problems and trouble. I have one right now on my pool pump. Starts off at the fastest speeds, then after a minute or two varies according to the conditions. Sounds like a great idea but I have already had to warranty it! Working OK now but if I had a choice (this one came with the new home we purchased) I'd have bought a standard model.

Although technology is always advancing, simpler is usually better if you are looking for longevity.
 
Oh- if you are willing to spend extra coin, invest it in a really good thermostat and a high sear rated unit. That will pay off.
 
Like appliances (Kenmore, Whirlpool, etc.), there are only a few A/C unit manufacturers.
 
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