Brand new home built, a/c poor air flow

[jcrum]

We had a new home built (2,800 sq. ft) living and we are having issues with the new a/c. Here are the stats of what we have:

Carrier Puron Infinity High Efficent Heat Pump
# 38YDB060320

On the air handler:
Cooling SEER 13
Heating HFUE/HSPT - 8.0
Condenser Model #38YDB060
Air Handler Model # FY4ANB060
KW of Electric Heat 10

The unit is still under warranty, and the company has been out several times. This is not a split a/c system. However, I think this unit was upgraded and it was a 2 motor system for a split system and they had to turn 1 motor off, seeing it was not installed as a split unit.

Breifly, thermostat read 75 degrees, and great room approx. 6 ft. from thermostat reads 74-75, however, are master bath at other end of home, will read 79-80. Also, no vent was installed in walk in pantry, which generates its own problems. I saw people were talking about an air flow test isp??. Who can do this? Also, how do you check for moisture control. I feel that the moisture is not getting out of the house.

I appreciate any advice you can give.

Thanks.

[scottsacavsfan]

For it to be 75 in one room and 80 in the other I think you are right on track with the air flow idea

dont let up on them this will be a life time problem if not fixed now!!!

call out a seperate tech to double check the work
maybe get 2 or 3 other oppinions
then take this info to the builder and ask him what to do
Dont be rude just get the facts and state you are uncomfortable in your new home.
It can be fixed but may be expensive to have duct work redone
it is woth it even if you have to pay a little extra
Correct duct work is more important then the name brand of the equipment.

Good luck
keep us posted

[beenthere]

If its not a split system. Why are you posting model numbers for a split system.

What you describe sounds like balance/duct problems.

5 tons for 2800 sq ft, sounds like it could be over sized. Which can cause high humidity in cooling season.

[jcrum]

I have thought to have a couple of other companies come out, however, I really did not want to pay for these other companies to review and not sure that this would just create a he said, she said type of situation. I am very frustrated at this point. They are supposed to come out on Tuesday and put in a bigger flex?? to the master bathroom, which may fix the temp problem. However, I am still dealing with a humidity issue also.

Out electric bill this month was $416 !!! For this being a new system, it just does not seem it is running very efficient.

Thanks for the quick input, I might have to rethink and just break down and call out some other vendors.

[skippedover]

First, I recommend that you keep a log of daily outdoor temps and the temps in several rooms and the type of weather (cloudy, sunny, rainy) for a period of a few days. I deally you would have a couple of days of nice sunny, warm/hot weather and a couple of days of cloudy weather. After you're armed with that info, you'll need a good company to do an analysis on the whole project. That will involve a load analysis and will cost you some money. No doubt any company that can do the load analysis can also see whatever problems you are having and can probably tell you what problems you have based on just the load analysis and how the ductwork matches up to that analysis. Pay for an estimate to do the necessary repairs and specify that if the company doing the consulting gets the job to do the repairs, the cost of the analysis is subtracted from the cost to do the repairs. Once you've got all that done, sit down and have a cup of coffee with the builder and explain all your problems and the quote to make it right. His people have already had their turn at making it right and haven't been able to help you. Loss of confidence there, I'd say.

Hopefully the GC is an upright person and will get the repairs done on his nickel. He'd be crazy to use anybody but the company that you consulted with but whatever. If he isn't an upstanding guy, then you may have a battle on your hands and it could go so far as a court battle. That's why it's so important to have a good, solid case before you sit down with the GC. That way he knows at the outset that he's screwed if it goes to court so, since your are being so nice about it, he's much better off to just do the needed repairs and put the whole issue to bed.

FYI, our company is currently working with a GC on a house he did 3-years ago and where the owners are very uncomfortable. I started out at square one with a load analysis. The result of that? 9-tons of AC needed in the home and it has 15.5-tons. Needless to say, they're not comfortable and the house is like a wet sponge all the time. We're trying not to throw the GC under the bus but his guy doesn't have a clue how to fix the house. Ducts? All flex everywhere. No real ducts. Lowest price, you can bet on that. Hope yours is better. :rolleyes:

[jcrum]

Well I wondered the same thing. I was told that we were upgraded to this unit because they happened to have this unit on hand or got a good deal or something like that and that we should be happier with this unit. However, after investigating, I was seeing that the #'s were corresponding to a split system. I know that when they installed, they had to come back and turn it on high speed.

Would installing this split system have an effect on the air flow or humidity?

Should they have not installed this unit for a single system?

[jcrum]

Don't you think that I should be able to get the Manual J and get a load balance test from the current a/c installer. Or do they not always do this. I know that they are still working with me, however, as of Tuesday when they enlarge the flex to the bathroom, they are thinking this will fix the problem. However, they have tried to use all kinds of excuses (bathroom window) we keep the blinds closed all the time and there are only 2 ppl in this house. Thank heaven there are not a house full. Plus, this time in Fla. is not the hottest of the year. Most of the time when the bathroom is up to 79 it is 8:30 pm.

The tech. stated that it was all up to the engineers ( they layed it out and did their calculations on how it should be done.

How do you know if the a/c is running the most efficient as far as electric usage? Can the electric company help us out there?

[beenthere]

Lots of 5 ton split systems installed and working fine.
That has no real bearing on your troubles.

It sounds like they may have just guessed at what size you need.
And at what size duct to run.

Ask them for a copy of the load calc, and the manual D.
If they come up with excuses. Then they didn't do any.

Keep calling your builder about the problem.

[jcrum]

Thanks guys.

I am going to ask for the manual D and the calcs and lets see what they say. I know I asked once before and I did not get and then when I asked again, I was told I would have to go thru the office for them. Go figure.

[jcrum]

By the way, what is the difference between a Manual D or Manual J?

Is there a way you can check for humidity levels?

[skippedover]

Don't you think that I should be able to get the Manual J and get a load balance test from the current a/c installer. Or do they not always do this. I know that they are still working with me, however, as of Tuesday when they enlarge the flex to the bathroom, they are thinking this will fix the problem. However, they have tried to use all kinds of excuses (bathroom window) we keep the blinds closed all the time and there are only 2 ppl in this house. Thank heaven there are not a house full. Plus, this time in Fla. is not the hottest of the year. Most of the time when the bathroom is up to 79 it is 8:30 pm.

The tech. stated that it was all up to the engineers ( they layed it out and did their calculations on how it should be done.

How do you know if the a/c is running the most efficient as far as electric usage? Can the electric company help us out there?

Sounds to me like they don't have a load calc nor anyone, let alone an engineer, designing the system. I'll bet all the supply outlets are the same size too! That's the first visual clue that in all likelihood, no load analysis was done. If they had a load, they'd have the duct sizes all mapped out and there wouldn't be any discomfort. I say this with confidence because I've personally done hundreds of load calcs and our company has installed literally hundred of systems without a single complaint of imbalance or discomfort. it's all in the numbers and yes, in a perfect world you could ask the installers for their load analysis. You can ask but I'm betting you get either blank stares or they shuffle out the door mumbling. There's a little primer attached to help you locate a good company if your installers don't turn out to be what you hope for.

[beenthere]

Manual J, is for determining the equipment capacity you need.
Manual D, is for determining the friction rate to use to size the duct system.
A hydrotherm will tell you your humidity level.

[RyanHughes]

Besides the issues being mentioned about ductwork and equipment sizing, this is a potential problem:

Infinity model #38YDB060320
Base model #FY4ANB060 (not variable speed; Carrier doesn't have them listed as a match in their Product Data)

Do you have an indoor and an outdoor unit, or just one package unit? A bit confused by your equipment description.

[jcrum]

Air handler is in the garage #FY4ANB060 and the outside Carrier unit is the model #38YDB060320

[RyanHughes]

They shouldn't have put that air handler with that outdoor unit. My guess is they got it for cheap since it's an old model.

[jcrum]

Is it the in the garage air handler that is an old model or the outside carrier inifinity series puron heat pump?

Here again they told me it was an upgrade from what we were supposed to get, so I thought great. Other people have told me that the air handler is not working properly and that is why we are not getting the air flow we need.

[jcrum]

Where can I find that product data matching on Carriers site?

[RyanHughes]

The outdoor unit is an older model. It is an upgrade from a base series outdoor unit, but with that upgrade needed to come at least a variable-speed indoor unit, hopefully the full Infinity setup. That air handler is a fixed speed air handler, not variable speed, which is pretty much a must for a 2-stage outdoor unit. Something you'll have to talk to them about. I doubt Carrier supports the combo you have, so you could use that in your discussion to get the right indoor unit.

Product data for 38YDB: http://www.docs.hvacpartners.com/idc/groups/public/documents/techlit/38ydb-3pd.pdf

Pages 16 and 17 have 060 model matchups. The FY4 isn't on there--only the FV4BNB006 and FE4ANB006 (both variable speed).

And likewise here is the product data for the FY4: http://www.docs.hvacpartners.com/idc/groups/public/documents/techlit/fa4c-5pd.pdf

[jcrum]

What is the difference between a fixed and variable speed air handler?

Would this cause our electric to run high also?

[RyanHughes]

A variable-speed air handler uses less electricity (more efficient). The variable-speed air handler can vary its speed to maintain proper airflow, and is installed as part of a 2-stage system for efficiency and proper operation. Results wouldn't be as good with a fixed speed air handler, hence it not being a rated match. That's about all I know on the subject, so I'll have to let those in the field give you more details (I'm a HO myself). I do hope you get the situation resolved.

[jcrum]

Thanks Ryan you have been a big help. I am going to contact Carrier tomorrow and also ask for the Manual D&J and load calcs, although, I think skip is right, they don't have them, but I will ask.

We'll see what happens.

Thanks again.

[RyanHughes]

You're welcome. Carrier's phone staff may not be of much help either, though you could always try (just recalling previous discussion of Carrier's phone staff results). You could still approach the builder and dealer and ask to see A. the load calculations and B. documentation proving that you were given a manufacturer-approved match.

[key1cc]

A variable-speed air handler uses less electricity (more efficient). .......... Results wouldn't be as good with a fixed speed air handler. That's about all I know on the subject..........

I must know less on the subject than you because I thought the variable speed motors could actually use more electricity if the ducts were undersized.....

Key1

[jcrum]

I will keep that in mind when I contact Carrier, however, I have a feeling that builder will push me off to the a/c vendor, seeing that we closed on the house already (approx. 60 days ago). However, I will give it a shot. Thanks again.

[RyanHughes]

I must know less on the subject than you because I thought the variable speed motors could actually use more electricity if the ducts were undersized.....

Key1

You are correct and I should have left that bit of info in my previous post. ECM motors are more efficient than PSC motors. In general, the ECM motors use less electricity, unless a ductwork system is very undersized (in which case they would use more electricity). Not only will they cost more $$$ to operate, but they'll also be louder...

But nonetheless, Jcrum needs the variable speed blower (model FE4A preferably) if he keeps the 38YDB.

[jcrum]

Ryan, we have printed the .pdf and we are armed and ready. we'll see what happens.

[jcrum]

Well from all info. I received today, you were right the outside unit is not matched to the air handler. In addition to that, you were right again the outside unit is a 2005 probably new but somewhere in the back of someone's shop.
Spoke with another carrier rep. today, he was very helpful, said to try and get them to change the air handler (FV4ANB006w/thermstat) to match the outside unit, that way we would have a matched system and get 14.5 SEER. If they change out the outside unit to what we should have to match the air handler we will only be getting 13 SEER.

Guess what, the a/c company, only wants to change the outside unit and give us a step down. They even won't admit that it is not a matched system. He stated he was not going to give us an upgraded air handler or in his words give us "gold". I said, you were willing to give us so called "gold" when you gave us a 3 yr. old outside unit that you had laying around. He said, if we wanted to pay $800-900, he would upgrade the air handler. Then he got a bad attitude and said if I wanted to wait and drag this out, that when I decided what to do, he would maybe get us scheduled in 30 days or so to take care of the problem.

Now waiting to here from builder.

Any advice on how I could push a/c tech. to upgrade.

[beenthere]

Keep nagging the builder.

[jcrum]

Yeah, I could only leave a msg. today, so hopefully I will get to talk them tomorrow.

[RyanHughes]

The FE4ANB006 would be the Infinity air handler. You could always ask for proof that what you have is an official match (which he doesn't have) and go from there. As beenthere said, keep pleading your case until you get it the way it's supposed to be.

[adrianf]

Does your state not have a building (energy) code that would require documentation of the installed system?

Do you have any contractaul documents from the builder/Hvac vendor as to what they were selling you?

[jcrum]

Ryan

Would the FE4 put us as 14.5 SEER?

The guy I talked to today, kind of, in a nice way said that this would be our best bet, seeing the they did not zone the house, it is 2800 sq. ft. living and he said it should have been zoned.

[jcrum]

Adrian

Unfortunately, the building dept. is stating that all they have to look at is if the unit was installed properly not match or ARI. I have spoken with them twice and I even work for the same county govt. for 20 years now, go figure.

The only thing that was put in the literature for the builder was that with an upgrade (which we got) that we would get a Trane or Carrier, 13 SEER.

[adrianf]

Ryan, others:

So there is no concern with reducing the air flow 50 +/- percent on the unzoned 5 ton duct system?

[jcrum]

Andrian

I may have confused you, when I stated "zoned" I meant that we did get 2 ac split system installed.

In other words, this other a/c tech. stated that we should have had like a 4ton and a 2 ton on this house, just going by the sq. ft.

[jcrum]

That was one of our main complaints from the beginning, that it did not seem like we were getting good air flow, of course, they passed this off as the new system don't give off as much as old and the 10' ceilings caused a problem.

[adrianf]

The only thing that was put in the literature for the builder was that with an upgrade (which we got) that we would get a Trane or Carrier, 13 SEER.

Which you did not get. Ask them to prove the system is a 13 SEER by providing the ARI certification. It does not exist.

[jcrum]

The only thing that was put in the literature for the builder was that with an upgrade (which we got) that we would get a Trane or Carrier, 13 SEER.

Which you did not get. Ask them to prove the system is a 13 SEER by providing the ARI certification. It does not exist.

We received a Carrier Heat Pump Infinity Series 5.0 ton. Adrian, what is not 13SEER. Do you mean it does not exist due to the mismatch of the Outside unit and air handler?

[jcrum]

The FE4ANB006 would be the Infinity air handler. You could always ask for proof that what you have is an official match (which he doesn't have) and go from there. As beenthere said, keep pleading your case until you get it the way it's supposed to be.

With this air handler, would we get a 14.5 SEER?

[RyanHughes]

With this air handler, would we get a 14.5 SEER?

Yes, it's rated at 14.5 SEER also, and it gives you the ability to use the Infinity control (the FV4 does not).

[adrianf]

For a system to be rated at specific efficiency and capacity levels it as to be matched/rated with both the indoor component and the outdoor component.

[RyanHughes]

For a system to be rated at specific efficiency and capacity levels it as to be matched/rated with both the indoor component and the outdoor component.

I was going by Carrier's ratings for the 38YDB.

[adrianf]

Ryan

My post was regarding the YDB on the FY fan coil. Sorry for the confusion.

[beenthere]

Adrian

Unfortunately, the building dept. is stating that all they have to look at is if the unit was installed properly not match or ARI. .

Ask them how it can be installed properly if its not an ARI match. Since the manufacturer only considers ARI matches as properly installed.

[beenthere]

Ryan, others:

So there is no concern with reducing the air flow 50 +/- percent on the unzoned 5 ton duct system?
That depends on what size the supposed 5 ton duct is.

[catmanacman]

I will keep that in mind when I contact Carrier, however, I have a feeling that builder will push me off to the a/c vendor, seeing that we closed on the house already (approx. 60 days ago). However, I will give it a shot. Thanks again.

i would stay after the builder they have to provide the warranty and here in Texas it is 2 years and if the installing contractor cant fix it then the builder needs to call and pay someone else to fix it

[jcrum]

Well, looks like we have a meeting with the a/c vendor and builder on Thursday. However, it looks as though they willing to trade out the Infinity unit and install a HBB carrier unit (which is what we were supposed to have in the first place).

My question: should this HBB carrier unit be able to cool our 2,800 sq. ft. home efficiently?

[RyanHughes]

If sized properly, with proper ductwork, it should have no issues cooling the place. 25HBB360 + FY4ANB060 would be a 13 SEER system nominally.

[jcrum]

Yes, it's rated at 14.5 SEER also, and it gives you the ability to use the Infinity control (the FV4 does not).

Unfortunately, they are not going to change the air handler to match the infinity series. The are going to replace the infinity with a 25HBB360C30 carrier 13 SEER and keep the current air handler.

Do you feel that this system be able to cool my 2,800 sq. ft. home efficiently?

[jcrum]

If sized properly, with proper ductwork, it should have no issues cooling the place. 25HBB360 + FY4ANB060 would be a 13 SEER system nominally.

Well, they have already been redoing ductwork prior to you informing me that we had a mismatched system. So I hope that it is correct.

Thanks for the advice again.

[jcrum]

If sized properly, with proper ductwork, it should have no issues cooling the place. 25HBB360 + FY4ANB060 would be a 13 SEER system nominally.

Can the 25HBB360 be any tonage? Because ours is going to be a 5 ton.

[dash]

Can the 25HBB360 be any tonage? Because ours is going to be a 5 ton.

The HBB3 is the base/builders model,13 SEER only,the 60 means it's a nominal 5 ton unit.

[bartdude]

It would be cheaper for them to replace the indoor unit unless they have a buyer for the outdoor unit.

[catmanacman]

i do not think the mismatch is the problem more likely a hacked in guessed at duct system also i would pay the extra for the vs airhandler and then when it still does not cool well have them rip out the duct and start over . do not let up until your system works properly

[jcrum]

Well, this is what was decided:

Install the proper air handler to fit the Infinity Series outside unit and also install the thermidstat. They say this should give us 16 SEER, which is better than we were supposed to get (which was 13 SEER).

This is going to cost us $900.

Even though this outside unit is 2005, the a/c contractor assures us that Carrier goes by the install date and that we will have a 10 year warranty on compressor and parts and 2 yr. warranty on labor.

Does this sound like a good way to go and do you think it will do an efficient job on this size house?

Any advice is appreciated.

[beenthere]

Sounds ok.
Are they going to balance the system also.

[RyanHughes]

Make sure that "thermidistat" is the Infinity Control thermostat to get the most out of the system (if they can make that work).

[adrianf]

Ryan

I'd guess they are using an FV a/h can the Infinity control work with that indoor unit?

[RyanHughes]

No, to my knowledge the FE4A is required for the Infinity Control but the FV4B would work with the thermidistat. By "proper air handler to fit the Infinity Series" and for $900 I'd hope they're installing the FE4A.

[DavidInAustin]

Don't you think that I should be able to get the Manual J and get a load balance test from the current a/c installer. Or do they not always do this. I know that they are still working with me, however, as of Tuesday when they enlarge the flex to the bathroom, they are thinking this will fix the problem. However, they have tried to use all kinds of excuses (bathroom window) we keep the blinds closed all the time and there are only 2 ppl in this house. Thank heaven there are not a house full. Plus, this time in Fla. is not the hottest of the year. Most of the time when the bathroom is up to 79 it is 8:30 pm.

The tech. stated that it was all up to the engineers ( they layed it out and did their calculations on how it should be done.

How do you know if the a/c is running the most efficient as far as electric usage? Can the electric company help us out there?

A simple service call from a reputable company should help emmensly. The checks that he/she will perform if done correctly will eliminate many issues that could cause this. Then you will be centered on the real issues at hand. Dont call the installing company for this. Installing companies often do just that...Install. They dont have a big service department. Thats not where they make their money - For that reason, they often have overworked inexperienced service persons - often just 1. Their installers can install, not service. Make sure you explain the problem in depth to insure the company that you select sends a qualified tech to get the correctr answers you need. You might even get a negociated qoute for the service before they come out.

My 2 cents. * When you buy a new home, because of the expenses to build one and make the profits that are sought by the contractor, they often choose the cheapest HVAC contractor in the tri state area, whom might not even have qualified help (or even a shop - they work out of their home). They (The HVAC contractor) often do the job for penny's on the dollar just to have work. They often go under - and there will be 25 more to take their place. They cant afford to do call backs. (They blame the engineering...as if there was an engineer!) They didnt make any money anyway. It sounds stupid, but its true. Pay a few dollars and get the right answers - Take it ( your findings from an independant company) to the Home builder and get your system fixed.

[jcrum]

Install 5 ton carrier variable speed air handler with edge control, FV4BNB006.

Also, I thought I saw on Carrier that for a 37YDB060 it states FE4, FX4, and FV4

[RyanHughes]

Yet again they're not giving you the full potential out of the Infinity system. Still better than before though. Ask if the new Infinity Control can work with the 2005 Infinity unit you have. I'm not sure if it can or can't to be honest, but I would assume it's still possible to get the Infinity system using your current 38YDB.

[jcrum]

Yet again they're not giving you the full potential out of the Infinity system. Still better than before though. Ask if the new Infinity Control can work with the 2005 Infinity unit you have. I'm not sure if it can or can't to be honest, but I would assume it's still possible to get the Infinity system using your current 38YDB.

They stated that they could probably get the brand new infinity series if we wanted to pay approx. $1,500; however, the only diff. was the cabinet, because we would still be getting the same seer of 16, if we kept the 38ydb and changed the air handler to match.

[Richard Kletty]

A simple service call from a reputable company should help emmensly. The checks that he/she will perform if done correctly will eliminate many issues that could cause this. Then you will be centered on the real issues at hand. Dont call the installing company for this. Installing companies often do just that...Install. They dont have a big service department. Thats not where they make their money - For that reason, they often have overworked inexperienced service persons - often just 1. Their installers can install, not service. Make sure you explain the problem in depth to insure the company that you select sends a qualified tech to get the correctr answers you need. You might even get a negociated qoute for the service before they come out.

My 2 cents. * When you buy a new home, because of the expenses to build one and make the profits that are sought by the contractor, they often choose the cheapest HVAC contractor in the tri state area, whom might not even have qualified help (or even a shop - they work out of their home). They (The HVAC contractor) often do the job for penny's on the dollar just to have work. They often go under - and there will be 25 more to take their place. They cant afford to do call backs. (They blame the engineering...as if there was an engineer!) They didnt make any money anyway. It sounds stupid, but its true. Pay a few dollars and get the right answers - Take it ( your findings from an independant company) to the Home builder and get your system fixed.

This is good advice. I do take exception to the "shop" part. There are several reputable companies represented on this forum who work out of the home.

Again, I agree with everything else though.

[RyanHughes]

They stated that they could probably get the brand new infinity series if we wanted to pay approx. $1,500; however, the only diff. was the cabinet, because we would still be getting the same seer of 16, if we kept the 38ydb and changed the air handler to match.

They're not giving you the Infinity air handler or Infinity control thermostat though.

[jcrum]

They're not giving you the Infinity air handler or Infinity control thermostat though.

Would this null and void any warranty from Carrier? I was told if we got the thermidstat, we would be OK. Is this going to give us 16 seer?

They are coming here on Wed. to install the new air handler and controls.

He faxed me a 2 page carrier flyer that stated "Performance Series" and it has the thermidstat control listed .

What is an "Edge Control"?

[DavidInAustin]

This is good advice. I do take exception to the "shop" part. There are several reputable companies represented on this forum who work out of the home.

Again, I agree with everything else though.

Noted and retracted. Thank you.

[RyanHughes]

Would this null and void any warranty from Carrier? I was told if we got the thermidstat, we would be OK. Is this going to give us 16 seer?

They are coming here on Wed. to install the new air handler and controls.

He faxed me a 2 page carrier flyer that stated "Performance Series" and it has the thermidstat control listed .

What is an "Edge Control"?

The FV4B is the Performance Series air handler. It is variable-speed. It lacks the Infinity interface that the FE4A (Infinity series) has, which would enable you to get the most out of the system. The warranty shouldn't be a problem since Carrier rates the system with the FV4B as well. The Edge is the new Carrier thermostat. If I recall correctly both setups get 14.5 SEER. If I were in this situation, I'd push for the FE4A so you have an Infinity system, not just the Performance and Infinity mixed. I'm not sure what the issue is with the builder's installer.

[jcrum]

The FV4B is the Performance Series air handler. It is variable-speed. It lacks the Infinity interface that the FE4A (Infinity series) has, which would enable you to get the most out of the system. The warranty shouldn't be a problem since Carrier rates the system with the FV4B as well. The Edge is the new Carrier thermostat. If I recall correctly both setups get 14.5 SEER. If I were in this situation, I'd push for the FE4A so you have an Infinity system, not just the Performance and Infinity mixed. I'm not sure what the issue is with the builder's installer.

Of course, Our main concern was that this be a "matched" system, which the installer stated it would be. From your comments, I am thinking it is not? What are we missing out on by not getting the FE4A? I am really getting stressed out about this whole thing. I can ask for the FE4A, however, I know they are going to fight me on it, just like everything else. Is the FE4A more expensive? Does it require more labor hours to install?

Is this maybe why he might fight me on this change?

[RyanHughes]

The FV4B and the FE4A are matches (both var. speed). You'll have to read about the Infinity control's capabilities on Carrier's website. I'll have to let someone else confirm if the current control can interface with the 38YDB (I assume it can). It will provide you with much more control and monitoring over your system. Should not be more difficult to install. Pretty much plug and play with the Infinity. FE4A probably carries a marginally higher price tag... not much. This is the air handler meant for Infinity systems.

[dash]

Your 38YDB was used with the FV and Thermidistat,for years before the Infinty Control and Air handler was on the market.

Fom what I've read,expect to pay something to get the Infinity System.

Edge is a new type stat from Carrier,can be a Thermidistat,which is what you should have with the system.