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Topic: Home A/C questions - any techs around here? (Read 1182 times) previous topic - next topic

Home A/C questions - any techs around here?

Well it looks like I’m in the market for a new home A/C system. The one on the house we bought was really undersized, but I hoped it would make it through the summer. Negative.

I wanted to see if anyone out there with a little more experience than me could help. The compressor blew on our system, but I really hate to throw good money after bad. Before the compressor went the house would only cool to around 85 in the heat of the day (central Texas) , and it ran almost constantly. If I just replace the compressor the house will still be too hot in the middle of the day. We have a bout 1800 sq. ft and it only has a 3 ton system. We are planning an expansion in the next couple of years that would bump that up to about 2400 sq. ft. so I think we are looking for at least a 4.5 to 5 ton system.

Of course I got the hard sell from the A/C tech – “your inside unit needs to be replaced at the same time”, “vents area all undersized for the new system”, “will have to install a new intake”, etc.

So what are your recent experiences? Can you replace the components piecemeal, or should it all be done at once? What size units do you run on your house? Any experiences particularly good or bad with the manufactures like Trane, Maytag, etc? What about some off the off brands like Goodman?

Any help would be appreciated.

Re: Home A/C questions - any techs around here?

Reply #1 –
When the ac went out on the last house I lived in, just the a/c unit was replaced, not the whole system.  I think it cost about $800 installed for a major brand (not sure on which one, but it wasn't generic.)  It was a low end, low efficiency unit, but was pretty inexpensive.  Where I live now we have a tiny little compressor unit for a 3 floor townhouse and it runs all day.  I hope it s out so we can get a new one.  The most important thing to consider is the size.  I wouldn't worry too much about an off brand as long as it has a good warranty, but never skimp out on the size.
1987 Thunderbird 3.8. Sold :(

1982 Thunderbird - Goodbye 255, Hello 302!

Re: Home A/C questions - any techs around here?

Reply #2 –
If it heats the house fine, then your furnace and all the ducting is in good shape. The outside compressor and a new evaporator should be all you need!

And good advice, make sure you get a good warranty!

Make sure the t-stat is in a central location in the house.

Re: Home A/C questions - any techs around here?

Reply #3 –
Thanks guys.  I want to go up in size a little from a 2.5 ton to a 3.5 ton unit and I just want to make sure the evaporator coil can take it.

I’m nads deep in research tight now.  I’m trying to separate the truth from the salesmanship (read as “bullsheet”).

Re: Home A/C questions - any techs around here?

Reply #4 –
I was in the same boat last year, old seer 8 unit, under sized for the house, $350 a month electric bill in the summer. I finally saved up enough cash to buy a new system. Problem 1 was that I could not find anyone to sell me a complete unit outright, unless it was a goodman or rhelm, all of the carrier, trane units had to be purchased through a dealer, I had one come out, and he told me the same thing. Vents to small, price to high, etc. I started asking everyone I knew, until finally I found a friend of a friend of a friend who was willing to sell me a system outright. I purchased a New Carrier 38tdb 3ton with puron 18 seer unit, I purchased the complete system, even the heater as it was more efficient as well. It was no problem installing it, I removed the old unit, installed the new one, ran the new lines, and only had to have the a/c guy come out and charge the system. After days and days of research online, it ended up costing $3000 cash and a weekend of my time. It cut our electric bills in half, and cools the house down down to 77 when it is 120 out. Unfortunatley, we are selling the house now, and the new house we just purchased is in a similar situation, even though it is new, the home builder installed the cheapest and most inefficient sysytem they could find, 2 Goodman unit's. So, this winter, I plan on doing the same thing over again, this time on the new house, and twice, since it is a split zone system. Good luck with your search.

Re: Home A/C questions - any techs around here?

Reply #5 –
I am in school for HVACR right now. Some of the things I have learned is that the indoor evaporator coil and outdoor condenser coil should be matched in order to be efficient(2 1/2 ton unit with 2 1/2 ton coil). ComfortMaker makes a few different brand units on the market. Most  brands contain a Copeland compressor, this year is a good time to replace your condenser/compressor unit because next year the standard will be 13SEER(more efficient yet more expensive)
Your ductwork cfm is really important for air conditioning over heating( more air circulation in a/c because indoor fan pushes the conditioned air through the vents with high fan, heating uses low fan) Return air important and use a non pleated filter when replacing your air filter, your furnace squirrel cage fan doesn't have to work so hard and more cfm.
I am not a technician, hope to find a job in the field, these are just some of the things we go over alot in class. I am through 26 of 36 weeks and am getting ready for the ICE exam and EPA test.

I have a Goodman condenser unit at my home right now and my teacher who works in this field everyday frowns on them. He installs ComfortMaker products.
I hope this may help

Re: Home A/C questions - any techs around here?

Reply #6 –
I forgot to mention, make sure you have a properly sized unit installed because too big of condenser can be worst than too small.  If the unit is too big for your house it won't run long enough to remove the humidity in the air while conditioning the space

Re: Home A/C questions - any techs around here?

Reply #7 –
Quote
old seer 8 unit, under sized for the house, $350 a month electric bill in the summer


That was me last summer, I had a 25+ year old GE unit, damm thing sucked my pockets dry in the summer. It strugled just to get the house to 76*. I bought a kenmore 14 seer unit (at the time it was the highest rated seer I could afford) I also had to shell out for a new heater (cracked heat exchanger). Total damage was $6000 cause I added the 5 year warranty. The worst part about it was that the 6k was from my car $$, hell I was going to take a picture of my heater/ac and make it my sig here :), l was able to put aside some cash and get alot done with the ride this summer so it all works out. House stuff comes first

My bills in the summer went from $325-$400 down to $120-$150 (my wife likes to put this thing down to 68-70*  :mad: and the winter gas bill went from $300-$350 down to $130-$150. So in a couple of years it pays for itself.

It's just a shame I didn't change them sooner when I first moved in
[SIGPIC][/SIGPIC]

Re: Home A/C questions - any techs around here?

Reply #8 –
I wish I could afford to do it right, but the tech is quoting me at least $7500 for the 3.5 ton system.

I'm going to see if I can figure out what the coil is rated for.  Should it be marked somewhere?
 

Re: Home A/C questions - any techs around here?

Reply #9 –
I looked at mine last night, there are no tags or markings on my coil to indicate what tonage it is. However, on the air handler unit that the coil slides into, there is a part number, not that helps. Any chance of you doing the installation yourself, it would cut that $7500.00 immensly.