Carrier vs Trane

[dbrown9429]

I am trying to choose between two systems: Carrier 24ABA342 3.5 ton up to 15 seer puron a.c. with FV4BNF005 20kw furnace or Trane XR13 a.c Model 2TTR3042A1000A with Air Handler 4TEE3F49B1000A 20kw. Both systems will use variable speed air handlers. Is this important? I live in a 2100 sq. ft two story in Missouri. My issue has always been cooling the second floor. Also, i am getting conflicting opinions on the use of R22 or 410 refrigerant. Is it true about the high pressure leak issueswith 410 or do I stay with R22. The R22 system with Trane is a liitle cheaper. Will there be any issues with these systems? Thanks for the help.
Doug

[grasshopper1]

I would defiantly go with the Carrier especially due to the R410a refrigerant. As the phase out of R22 creeps up on us, 410a is getting less expensive and R22 is going up. When buying a system you want to consider future maintenance and repair costs. The Trane is also available in in 410a but there technology is not proven like Carrier who has been using 410a for years and together with DuPont created the refrigerant.

[jimj]

The Trane is also available in in 410a but there technology is not proven like Carrier who has been using 410a for years and together with DuPont created the refrigerant.

I put my first Trane R410A system in about 8 years ago ( given to my company and customer for free as a test system). Believe me there 410A technology is just fine.:D

My advise, chose the installing company BEFORE the brand.

[RyanHughes]

You're comparing a builder model Carrier with a more premium Trane unit. I'd choose the Trane if presented with those two options, if nothing else for a better warranty on the compressor. The 24ACA3 and 4TTR3 would be a more fair and even comparison. I personally don't see a big problem with going with a R-22 system, but at this point, with R-410A becoming the new standard, I would advise you to go with an R-410A system. In this case, the Trane model numbers would be 4TTR3042A1000A and 4TEE3F49B1000A (14 SEER, like the Carrier matchup).

What is your source of heat? Hopefully not just the $$$ electric heat. You could ask for a price on a heat pump instead (can heat and cool--4TWR3042A1000A from Trane). You say you're having trouble cooling your second floor. What have the contractors proposed to solve this issue? Hopefully not just automatically increase tonnage, as sometimes this can make things worse. Has your ductwork been thoroughly looked at (enough return, etc.)?

[BaldLoonie]

What does the heat gain of the house say? Bigger isn't better, especially when trying to cool the upstairs more. Big A/C cools downstairs faster, shuts off leaving up hotter. My first year of selling, go to house about your size, 3 tons. Guy says go bigger to cool upstairs. I say no, go 2.5 ton to cool upstairs. He believed me and found I was right. Long run times spread air around better cooling more evenly. But I had a heat gain calc to back me up. I don't downsize without it!

I also wondered why no heat pump!

[AggieEngineer]

...like Carrier who has been using 410a for years and together with DuPont created the refrigerant.

Allied Signal, now Honeywell, patented it and developed the refrigerant (R-410A) in cooperation with Carrier.

[Nytefog]

Variable speed AH will only intensify the second floor air flow issues. You duct system needs to be evaluated. Zoning might be a viable option to correct the issue. You need to address this issue with your contractor.

[dbrown9429]

Nytefog,
Thanks for the info. When you say intensify, do you mean the problem could increase? I am continually being told that the variable speed will help with this issue. By the way, I remember being told I was just at the square footage(2065) of house that could rely on a single unit instead of zoned systems. The only contractor that actually did a heat calculation proposed a 4 ton unit which is an upgrade to my current 3.5 ton sysytem but I have been told that bigger is not always better. I currently close dampers on each side of main plenum in summer to force more air upstairs and then I open them up in winter. Are heat pumps a better way to go? Thanks.
Doug

[Nytefog]

Yes, the problem with airflow, and temperature difference, will only become worst with a variable speed unit if the duct work has issues. A zoning system is meant to increase comfort and regulate temperature in different areas, and is said that i can also conserve energy. The zoning that I’m talking about is a single system with motorized dampers and two thermostats. If you already have to separate trunks for the first and second floor then it shouldn't be to hard have zoning installed. You could benefit from a heat pump depending on where you live, but they are more expensive than a condenser.

[RyanHughes]

How would a variable-speed blower make things worse in terms of airflow? It may be louder if the ductwork is poor as it ramps up, but it should be at least as good as a standard blower, if not slightly better due to the ramping to maintain set CFM. Am I wrong? Please explain what implications you see with the variable-speed blower.

[rponson]

Yes, the problem with airflow, and temperature difference, will only become worst with a variable speed unit if the duct work has issues.


Please explain this. I am not sure i believe it but I would like to hear your explaination

A zoning system is meant to increase comfort and regulate temperature in different areas, and is said that i can also conserve energy. The zoning that I’m talking about is a single system with motorized dampers and two thermostats. If you already have to separate trunks for the first and second floor then it shouldn't be to hard have zoning installed. You could benefit from a heat pump depending on where you live, but they are more expensive than a condenser.

xx

[Nytefog]

I was recently taught in duct design class to never put a variable speed furnace/AH on a poor duct system due to the fact that it will only exemplify current air flow issues. I have experienced first hand complaints from customers that the delta T between 1st and 2nd floor has become significantly worst after the installation of a variable speed furnace.

Since the furnace runs on low speed, primarily, the rooms that already have poor airflow will only become worst. Perhaps when the blower is on high their will be a very slight increase in airflow but, for the majority of the time the furnace/AH will be on low. A variable speed unit should never be sold to correct an already poorly designed duct system.

I’m just suggesting to this individual that just installing a larger capacity unit with a variable speed motor is most likely not going correct this issue. The duct system needs to be evaluated. Bust out the magnehelic and goto work!

[beenthere]

Since he is using an air handler, and not a 2 stage furnace. He won't have the problem you describe.

I have never had the problem you describe with a 2 stage furnace with a VS blower.

Since in first stage, you don't need as much air to either floor.
The duct system isn't undersized for first stage.


If the duct system is under sized for first stage, then its grossly undersized, and a new single stage PSC blower won't work either.

The only fix then is duct work alterations.

[dbrown9429]

Thanks for the input. I do not think I have any issues with the ductwork. On that note, I had a contractor suggest the Honeywell zoning sysytem. I do have a single trunk running up to the attic where it branches off into the bedrooms. He said the same thing, that it would be easy to control the airflow with the dampers. However I have tried this with manually controlled dampers that I close in the summer, trying to push more air upstairs. I just have not had much sucess. The basement and first floor are cold and it is still uncomfortable upstairs. I did not know that you could zone with a single system. It seems like a good idea. Really, what other choice would I have? I am considering going with a two stage heat pump and high efficiency air handler. I will see how it goes. Thanks again for the input.
Doug