I suggest getting the Carrier coil. Get either the tin plated coil or the all aluminum. I would like to see who says ADP coils are better than Carrier's?

You have been offered AC condensers in two different sizes (3.5 ton and 4 ton). Did the contractor do a load calculation? What is the typical summer high temperature? Depending on your electric rate and how much you use the AC, a 13 SEER AC may be OK. Normally 15-16 SEER are the best value. Take a look at the Performance AC condenser is you want save some money over the Infinity model.

I think your furnace is over sized at 110,000 BTU. I didn't think it got that cold in the Bay area.

I thought the same about the furnace being oversized. Very odd.

What thermostat does system have?

What is typical summer weather for your location?

I would not recommend a low end condenser like the base series you were quoted nor a third party coil. Plus the third party coil might affect warranty on the Carrier condenser.

Are you dealing with a Carrier dealer? It's difficult for me to understand why he would recommend a third party coil which leads me to believe he is looking out for himself, not his customer.

IMO

The furnace came with the house so there's nothing i can do about it.

The summer in our area is actually not bad at all. Hopefully we'll only turn it on when the heat wave hits (which probably ~10-20 days in a year) so that's why we're being recommended to use the basic unit instead.

Our thermostat is just the basic Carrier one that comes with the furnace.

My dealers are Carrier dealers (got quote from several people that's why you're seeing different tonnage recommendation) and all of the quote i got recommends the 3rd party coil. Everyone said it's due to the space restriction + cheaper. I even called up Carrier customer service to ask if it's ok to use ADP instead of Carrier coil and he didn't oppose it at all. He said it's absolutely fine and won't affect the warranty. I find it really weird that he didn't push me to go for Carrier coil and even sounded supportive for using ADP coil.

There was a period of time when Carrier coils were failing so I can imagine some contractors looking to use another coil. Hopefully Carrier has figured out how to make a reliable coil again. It should not be too difficult. I had Carrier coils in my two old furnaces. They had no problems during 25 years of service.

If the ADP coil is a better fit, and Carrier will honor the condenser warranty, then you shouldn't have a problem. Get the Carrier dealer to put this in writing for you.

It would be nice if you had the Infinity controller. Ask the Carrier dealer how much he wants to add one to your system.

Thanks everyone for the input.

We're planning to get the Nest thermostat when it goes on sale so i think i can stick with the basic one for now or do you think Infinity controller is more recommended than Nest?

The Nest thermostat may or may not work well with the Infinity furnace. It is not going to be able to display the diagnostic codes when the furnace is having problems. I am not sure if it will do a good job of controlling the two stages of the furnace. You are better off with the Infinity controller in my opinion.

There is a new Infinity controller which supports WiFi.

Thanks for pointing it out, Mike. Btw, we were told that I might be able to use the Carrier coil after all. Carrier website mentioned that they're using all aluminum now but tin-plated was highly recommended in this forum. So if I have a choice, should i pick ALA or ATA?

ALA replaces ATA....

The Nest is a mistake for an Infinity furnace.

IMO

ALA replaces ATA....

The Nest is a mistake for an Infinity furnace.

IMO

I was told that ALA is introduced mainly for cost reduction, not for quality improvement. Is it true?

Hi all,

We are going to have our install this week and we are planning to have these after some consideration (thanks for your suggestions too):

The Infinity 17 2 stage unit (24ANB748A003): to match with our 2 state furnace
21â Carrier Coil (CNPVP4821ALA)
Carrier Infinity TOUCH thermostat with WIFI

The condenser and thermostat add $1500 from what we originally plan to have (just the basic 13SEER unit + use old basic thermostat). Is that a reasonable price? We will qualify for $300 federal tax credit and $250 Carrier cool cash rebate.

We will be replacing all our ducts as well since the old ones are 40year old + lots of rust.

Right now, i'm very tempted to have some zoning done too (might as well go all out :p). Supposedly the Infinity thermostat can control up to 8 zone. But I heard the zoning will cost at least $2k extra so i'm not sure if it's worth it. My house is 2000sqft, 2 stories and upstairs probably only account for ~500sqft (only have 2 small bedrooms + 1 bathroom). Would you recommend spending that money? Or is there anything simpler I can do to make the upstairs cool in a similar rate as downstairs?

The simplest and least expensive plan of action would be to have manual damper control on supply trunk line to each floor. 2k is pretty expensive considering you are only talking about 2 sm bedrooms and a bath, 500 sq ft. Size of supply runs also should be looked at.

IMO

I'm having my unit installed today. I've read that they should braze with nitrogen to minimize flakes. I saw nitrogen tank so i didn't remind them of that. but I just found out after they didnt braze with nitrogen. now i'm freaking out. the main guy says that they will do more nitrogen purge/flush to get rid the flakes + vacuum will suck the flakes out??? + there's drier filter to catch the flakes. will it help? is there other way to get the flakes out of the system now? most driers are in the liquid line, upstream from compressor. The particles will already go through the compressor before it gets to the drier. So damage has been done T_T

Many installers do not braze with nitrogen and it is sad. Sometimes you really have to breath down their neck to make sure things are installed properly, and as the homeowner that really shouldn't be your job. Yes, many systems are installed this way and never have any major problems in their lifespan due to this. However, the results often include clogged metering devices and therefore lesser performance and efficiency. I disagree with the statement that the vacuum pump will suck out the flakes -- it won't. Filter driers may catch the flakes, but then potentially clog and create a restriction. Some units come with a filter drier factory installed, and if they added another one, they've created another possibility for a restriction.

This post was edited by ryanhughes on Thu, Jun 6, 13 at 19:13

So... they're taking apart all the weldings today & giving me a new coil. They will put new weldings near coil but will only use brush to clean the weldings near the compressor & install suction line filter drier (i can either leave it on or take it out after some time). Is this good enough?

Beth,

I got some information about the Carrier ATA and ALA coils.

I talked to the my HVAC contractor while he was doing the maintenance service on my Carrier condensers. He did the installation 4 years ago. I find he is very knowledgeable and very honest about anything I ask.

It is true the Carrier ALA aluminum coil is a cheaper version of the tin plated copper ATA coil. The tin plating on the ATA coil was an fix to stop the leakage problems of the copper ACA coil. The contractor gave me a white paper written by Carrier explaining the corrosion problems with copper coils. There are pictures of corroded coils from several manufacturers (Carrier, Trane, Goodman, ADP, Rheem, Supperior, etc.). It seems everybody in the industry has had coil failures due to corrosion. The corrosion is created by corrosive agents inside the house and not by manufacturing defects.

I also asked about ADP vs. Carrier coils. The ADP coil is cheaper than the ATA coil, but the same price as the ALA coil. He said ADP only has a 5 year warranty. I am not sure if that is true. The ATA coil is being phased out. At some point you will only be able to get the ALA coil.

Did you get your installation issues resolved? Is the system working well?

Hi Mike... Thank you very much for the follow up. I ended up with the ALA coil because ATA is no longer available. But I was told that ALA, even though it's cheaper, it actually can withstand the corrosive agents better???

My AC is now up and running ^_^ The only question left is should i take out the suction line drier. Any advice?

The ALA coil may be able to withstand corrosive agents better since it is made out of aluminum. These things take years to surface, so time will tell. I have to believe Carrier has put a lot of money into coming up with a good solution. Having thousands of coils fail under warranty in the field is very expensive.

I am no expert about the suction line drier. My advice would be to leave it in.

So it's been a while. How did it hold up?