Best Evap Coil

[spudraleigh]

Hi,

I am buying a Carrier Infinity 38TDB942 3.5 ton AC, 58MVP080114 2 stg furnace, and Infinity Thermostat. What is the optimal coil for this use with the best balance of efficiency and durability?

Thanks in advance for any insight you can provide.

David

[karsthuntr]

Shouldn't you let your installer decide that?

[spudraleigh]

What kind of answer is that? I am asking for a professional opinion on what others might consider a good choice and your answer is less than helpful.

Please - only post an answer if it is in some way helpful or meaningful. Thanks.

Dave

[t527ed]

the one carrier says matches unit

[karsthuntr]

They do not make a 3.5 ton infinity.

[mech890]

Any brand of coil but Carrier

[dash]

Originally posted by karsthuntr
They do not make a 3.5 ton infinity.

No,they do not,check your numbers .

[Irascible]

I think karsthuntr gave you the best answer of all spud. If you research enough you should come to the conclusion that picking the best contractor is by far the single most important step in buying an HVAC system. And if I were spending the kind of dough that you are on a top of the line system, I sure as shoot would make sure I had a competent contractor.

That being the case, second guessing his decision on something as esoteric as coil selection is odd. If you’re concerned that your contractor isn't picking the right equipment then you perhaps your question should be about picking contractors, not coils.

As to your question, the best brand is Carrier simply because you need a coil and AC that will deliver a capacity that matches what the heat load calculation calls for. Carrier is only going to test and publish data for their AC and coils. The same goes for any OEM. So if you're looking for a fine tuned system with a particular output then coil + AC match-ups should be kept the same brand so that you have data to work with. The best coil within Carrier's line is the one that delivers an output that best matches your heat load calculation.

[rasmussen6880]

The instalation is every thing. i have seen the bigest pice of junk in town instaled corectly perr like a kitten. Ive allso seen the top rated stuff with problem after problem that could have been avoied. there isnt 100.00 dollers worth of difrence from one brand to the other for like models

[spudraleigh]

Okay, so far you have corrected me on the 3.5 vs. 4 ton and it is true, I had mispoken, it is in fact 4 ton. Now let me rephrase the original question so it makes more sense. Please do not reply with anything like "get an installer I trust" since I have read that 100 times along with "a poor installer can make the most expensive equipment perform like crap and vice versa." I get it, okay?

Assuming all else is equal (i.e. I have the world's most trustworthy, knowlegable, and experienced installer, Infinity A/C, Controller, and Furnace all installed in a way that would make any professional proud), what is the most efficient indoor evap coil? Is an n-coil more efficient or better in any way than an a-coil? Is a Carrier better, worse, or equivalent to an ADP (in efficiency, durability, quality of construction, etc)? What model of Carrier or ADP is recommended for the highest SEER?

I have read a ton of data on this and would really like to hear some technical details on this topic since, other than the ARI ratings, the coil thing seems to be somewhat of a black art. Again, thanks in advance for any insight you can provide.

David

[Irascible]

Seer data is available. I'm sure someone will volunteer that. But in my opinion beyond the SEER rating you're looking for answers that aren't there. Others may disagree. If so then let's see the data. Do we have Consumer Reports or JD Powers info on which coil is the best? Hardly. Nor is there even consensus amongst contractors. You'll find guys that hate and others that love Carrier coils. The same is true of any brand. Any style of coil you just mentioned could work just fine if the ducts and blower are properly sized. If I were an engineer I could design a horrible a-coil and a wonderful n-coil for your application and vice versa.

The best coil is the one that has been tested with your AC and therefore has data that shows it will give you the sensible and latent capacities your heat load calculation calls for. The other useful bit of data is its pressure drops at various airflows. That is used to determine what size ducts and blower you need. I'm sure such data is available for Carrier + Carrier systems. I don't know if such data is available for Carrier + ADP. I know they have SEER information available for ADP. I just don't know about sensible/latent capacity information.

The only other useful thing I can volunteer is what I've been told by Trane. The SEER rating from third party coil OEMs is in part or entirely based on computer modeling. As such they sometimes get a little loose with how they do things and perhaps give higher ratings than they deserve. In the case of Trane at least (and probably others) they test actual equipment and don't have as much room to fudge the results.

[Edited by Irascible on 07-02-2005 at 09:45 PM]

[docholiday]

Iriscable, I think your right. The way I understand it is that they computer simulate the efficiencies. Unlike OEM's who have random units selected and tested by ARI (OEM is not allowed to be present) and have a 5% (May be less) tolerance. After market mfg's have double the tolerance since they are not using actual testing. Frankly, I find this unfair. I have heard that come January the computer simulation and higher tolerance goes by the wayside.

Now to the OP. The Carrier Product Data Sheets have the information you want. You need to make a selection based on efficiency and capacity and consider the sensible ratio using the conditions you are dealing with. If its a heat pump you need to consider the heating efficiency as well. There is no one answer or there would only be one choice. I recommend you find and read the product data sheets to determine which coil is best for your application. You can also access this information at the ARI Primenet website.

[Irascible]

Tanks. I'm glad someone recognizes genius when they see it. LOL!

[bittan]

Have had wacky times explaining the Infinity T'stat to homeowners. These are usually tech savy people. Once they press and hold the ADVANCED button for 15 seconds you open up a can of worms. These home owners try to ask, analyze and quantify every feature and reading logged in this stat. FYI, that little ECM inducer HUMS at 4000 rpm. Seem to get nuisance calls about them. Ask them if they hear it only when they stand 3 feet from the furnace. Answer- Yes. So I can only reply to stand futher away from it:-)

Get the Carrier dealer to match you up properly and do a top-notch install.

[jthomas21]

I have a similar system, but have a 3 ton. I picked out the equipment myself with the help of Carrier experts. I was advised that the CK5P coil was the one to use with the 38TDB.

http://xpedio.carrier.com/idc/groups...e=PdfHighlight

[spudraleigh]

Okay, one more Q and this is the last (until I think of something else). Is an n-coil inherantly better at anything than an a-coil? I would think so because of surface area alone (again, with all other things being equal).

[Irascible]

It depends on the a-coil and n-coil. I installed a 5 ton high efficiency Trane a-coil once that from certain angles looked nearly as big as the furnace. It had some major surface area.

[jpb2]

Sorry, Willis does not have the best game in town. Check out the Ruud modulating furnace. With the new 2 stage a/c it can't be beat. i back my dealers better as well

[John Winn]

From what I have been shown, the best for SEER is not a Carrier..I have been having issues with my Infinity system and had an authorized Carrier guy come out for an eval. He has a book, a hard three ring binder which says carrier on it and the local carrier distributor. In the book it lists the carrier units, by condensor, furnace, coil and what the price and SEER is. (cause of the price he wouldn't let me peer into it) but he told me, that the way my system is set up, which is according to Carrier, is a 14.5 seer. But, below this, there is another coil choice which I am sure he told me wasn't Carrier, but in fact raises the SEER to 16. He told me that he never installs the factory coil as he strives to give the customer the best efficiency so he uses the "after market?" unit? Point is there are choices which are in fact recommended for the units..Or at least appear to be..

John

[gencon]

rasmussen6880
Boy, it sure get old hearing the "in the installer stupid"
If you believe that I have a Kia that I'll sell for $100 less than a Lexus; according your logic it will be a good deal!
gn