Carrier would have provided a free heat exchanger under the lifetime warranty. The home warranty company could have installed it, or better yet I would have hired a Carrier Factory Authorized dealer and give the warranty company the bill.

The equivalent furnace would have been the Infinity 59TN6. You then could have kept the Infinity controller. I don't think the 59TP6 is a true variable speed furnace. I think it is a multi-speed motor that is set during the installation to a set speed. The Infinity variable speed furnaces has a DC controlled motor which will spin at whatever RPMs is required to get to the desired air flow.

You are losing all the diagnostic features of the Infinity contoller. How could the warranty company think a cheap non-programmable thermostat is would be equivalent?

The fact that the heat exchanger failed in 7 years suggest that the initial installation was bad. The static pressure (which the Infinity controller measures) may have been very high causing the heat exchanger to run hot. I would feel better if you hired a competent HVAC professional. These warranty companies are not very competent and will substitute the cheapest equipment possible.

I believe these warranties are supposed to replace the item (if they can't fix it) with a comparable one, if the original is no longer available? Have you read the details of the warranty?

Let me try to respond to what has been asked:

• I knew the original furnace was under Carrier warranty (lifetime heat exchanger, 10 years everything else), but the tech implied Carrier might try to deny warranty or at least drag out the process and I was without heat in the middle of winter. There was also the concern about what caused the exchanger to fail. When the warranty company offered to replace it in a few days I said okay.
• I called Carrier after the fact and they confirmed that they would have only replaced the heat exchanger. Seems they have plenty of those in stock.....
• The home warranty in the non-fine print says they will replace equipment with equivalent features. The fine print says that for furnaces, it only has to have the same "capacity" and it is even up to their discretion to replace with like efficiency. The fine print also says they only will use a builder grade thermostat in the case a new thermostat is required.
• I went back to our real estate company that sold the warranty and pointed pointed out there could be legal issues with the interpretation of "features" vs. "capacity" and they are now pushing the warranty company to match "features"
• Now that I have gotten the real estate company to push the warranty company to match features, I need facts to prove that whatever cobbeled together system the HVAC company says will be have the same features actually won't unless they put in an Infinity furnace and put back the Infinity thermostat.
• I have reached out to a very well reviewed HVAC company that comes up on a Carrier search and says that Infinity is 90% of their business. I want them to look at my current system to find any issues from the original install 7 years ago and also to come back once the warranty company's HVAC contractor is done to fix whatever is wrong from them.

I find it curious that the warranty company discouraged you from replacing a part that would be free and instead gave you a brand new furnace and thermostat. Their HVAC contractor must have talked them into this. It makes no financial sense.

There had been a week and a half where they had sent another tech out 3 separate times and he never "observed" a problem. Due the the hole, the furnace would throw a high pressure limit error. Since we were cold, we would reset it after it cooled down and it would run 12-36 hours before it failed again. The 1st tech said he could not repair anything unless the error code was actively showing and/or there was an observable physical problem. I didn't know at the time the Infinity thermostat stores codes and the video we took of the code wasn't good enough. He said the hot temperature of the metal above the heat exchanger (it was too hot to touch) was normal and he did not find the hole. The exhaust also smelled bad outside and there was an odor inside which he also said was normal. After the week and a half I demanded a better tech and thats when they sent the guy who found the hole. I had escalated this up the chain at the warranty company and I think they just wanted me to go away which is why they decided to replace vs repair via Carrier.

The story here is a nightmare...Just curious, who kept that working Infinity controller...several better options than what you are left with...including the replacement of the heat exchanger or a cash settlement...wrong thermostat with that replacement thermostat...at best it should be Carrier Edge Thermidistat...these 3rd party warranty companies sit on the close edge of providing shoddy work and are notorious for looking out for themselves rather than their customer...

IMO

The HVAC company has the Infinity controller and are happy to return it. My main reason for starting the thread was that the warranty company is proposing installing an Edge TP-PRH01-A to get back the the same feature set I had originally and I am trying to determine what will still be missing if that is done.

The list I have so far:

1) No continually variable fan

2) No diagnostic info

3) Inability for A/C and furnace to communicate to run condenser and fan at ideal speed for cooling and dehumidification

4) Ability to go multi-zone in the future

5) Inability for A/C to run at different speed on its own (?)

One thing I am curious about: does the TP-PRH01-A require there to be a whole house dehumidifier to work properly, or will it control the Infinity condenser to dehumidify? If it can control the condenser, I know if won't be "as good" as if everything was Infinity but what will be missing?

I am particularly interested in the ability of my original system to run at very low speed when it was 55 degrees outside but high humidity to dehumidify the house. I found that to be the best part of the Infinity system and what I am demanding I get back.

When the warranty company offered the replacement, I was given the option of cash instead but it was only $1800. Thinking I was getting a new Infinity furnace, I decided to take the furnace. Yes, I should have asked for the exact model that was going to be installed. For reference, I have gotten a quote from a registered Carrier installer to put in a new Infinity furnace for $5800.

The Performance 59TP6 is a two stage var speed furnace 96% efficiency. It requires Carrier Edge Thermidistat not the HW Mdl installed. The major negatives of this furnace over what you had was loss of full communication feature and diagnostics. I would get that controller back. You could probably sell it. What Mdl AC do you have if any? Another negative is you might now have a mismatched system not AHRI approved. Sorry for your trouble but you did not ask the right questions and as said before these 3rd party warranty companies sometimes cause more trouble than they solve.

IMO

Its a 7 year old Carrier Infinity A/C. Don't know the model info off the top of my head since I am traveling

Well I feel certain you now have a mismatched system. Will it work properly? Probably yes but...if you plan on keeping this new furnace, I definitely would have the thermostat replaced. But before you do anything further, I would get a Carrier FAD involved to get his advice.

IMO

I know I have a mismatched system. I was hoping that someone here could help me determine what features will be missing/degraded with the Performance furnace and the Edge thermostat.

I am not familiar with the "FAD" acronym. I did send a request to Carrier for this info via their web form days ago, but like most companies my request seems to have gone into a black hole.

FAD means Factory Authorized Dealer. It is classification which some dealers received. Must understanding is a FAD must receive additional training in order to get this classification. There is a the President's Award which I think is based mostly on the amount of sales.

You have the most important features on your list. You won't get much of a response to Carrier. The most they are going to say is to discuss your questions with your local Carrier dealer.

Was the quote of $5800 for the 59MN7 or the 59TN6? In either case that seems like a very high price to swap out a similar furnace. You could have kept the old Infinity controller.

My A/C is a 24ANA748A300 (thanks to my wife for going out in the cold to check)

The install cost was for the 59TN6 I think

I could not have kept the Infinity controller with the Performance furnace, but yes it needs to be returned to me.

Per this document: 4ANAProductData The Infinity controller is needed to do low ambient temp (0-55F) dehumidification. That is hopefully the key I can use to get the proper furnace from the warranty company

Another question: will/can Carrier void the warranty for my new furnace if it was not installed by a FAD?

No, not as long as you properly register your new furnace for the warranty.. This is something you need to understand and follow up on. I believe it can be accomplished online. Certainly don't rely on the 3rd party warranty company to do this.

IMO

If the quote was for the 59TN6 then it was really high.

The Performance Edge thermostat can also cool to dehumidify. That with the 2-stage AC will provide good humidification performance. I would think it would be as good as the 58MVB furnace. I would think the Edge thermostat and Infinity controller would act the same way in controlling the humidity.

Once the Edge thermostat is added you will have a nice system. You will have a tough fight to get the warranty company to give you an Infinity furnace. You can certainly try. Keep us posted as to what happens.

So the language about needing an Infinity controller to use low ambient temp is outdated and the Edge can do the same? There is this note in the above linked manual under low ambient cooling:

“ Standard with Infinity Control (non---communicating thermostat is not allowed except for emergency use).”

Seems like a great cause for Carrier to void the warranty on my AC condensor.

Just curious...what size 59TP6 furnace did 3rd party warranty company install?...post complete model number...it must have a 4 ton rated blower for that 4 ton Infinity AC condenser...

Not sure what low ambient dehumidification means. You are not going to operate your air conditioner below 55 degrees to dehumidify your house. Why Carrier would even list that as a feature is strange.

The link you provided is the product data for the 24ana1. You have a 24ana7 condenser. Here is a link for the correct product data document. I have the same condenser. I also have the 58MVC furnace which is 3-stage version of your old 58MVB.

Here is a better argument for your case. This is found on page 4:

This note is saying you must have an Infinity controller to properly operate your air conditioner. But then the controller would be incompatible with your new furnace therefore you have to get a Infinity furnace. I am not sure if I really believe this. But then again you would think Carrier would have included the Edge thermostat in this statement if it were an acceptable substitute.

I have a 100k BTU replacement furnace

I suspect oversized...I would think 3rd party just gave you what you had. What size home and location pls?

IMO

An oversized furnace with undersized duct work can cause the heat exchanger to run hot and have a premature death. The heat exchangers in high efficiency furnaces must have high thermal transfer characteristics. This means thin light weight metals.

As mike_home said, the Infinity has a continuously variable DC blower. That blower is by definition, more efficient than the two-stage blower in your new Performance model. The warranty company has no case here, either on efficiency or features.

I got a second quote from a FAD and came in at about $7k, so labor must just be pricy around here. I had the 2nd vendor run a rough sizing calculation and it came out to 80k BTUs, so this apparently lines up with the 1st stage of the Infinity puts out.

I plan to continue to push the warranty company

FUD means Fear, Uncertainty, and Doubt, FAD means Factory Authorized Dealer. Don't work with a FAD that promotes FUD. :)

edited my earlier post from FUD to FAD. Thanks mike!

Back to an earlier question, the house is about 2200 square feet. We are considering finishing about 400-800 square feet of the basement and in that case is the current 100k size of the system + Infinity zoning sized well? If I end up replacing the furnace on my own I'd need to know if I should downsize to 80k and/or if Infinity zoning vs a separate (ductless) system for the basement would be a better option. Zip code is 22015 (northern Virginia).

Also, the FAD that gave the $7k quote didn't have great things to say about Carrier and suggested that due to the age of the A/C unit, if I was going to buy a new furnace we might consider starting from scratch with a Daikin system that they also carry and recommend over Carrier. Nothing is ever simple, right?

A basement creates a small heating load, and no cooling load. Even with a 80K furnace you could keep the house and basement toasty in the winter. You could make the basement a separate zone if you want more precise temperature control in the winter. In the summer the basement should always be cooler than the upper floors.

The FAD is suggesting you replace a 7 year old condenser that is still under the parts warranty? He is suggesting you replace everything with a mini-split. I guess this FAD is getting to leave Carrier. His recommendations make no sense, and he is very over priced. This sounds like a FAD promoting FUD! (sorry I couldn't resist)

The ductless system was just for the basement. I'll start a new thread related to the basement HVAC