Carrier heatpump problem

[joehfd]

Hello I am new here and I hope I can get some answers. I had a Carrier Heat pump installed it was a 2ton system model 25hca324a003 with a fv4bnf002 Handler. The problem is the system would not bring the temp below 73 degrees and after having the installer back several times he replaced the 2 ton unit with a 3ton unit. My problem is that the system is still not running right. I went into the attic and inspected the duct work and it is only 12 x 12 at best running off the air handler and the return is 14 x 30, the square footage of my house is only 1250
Is the handler compatable with the 3 ton unit and does the duct work seem right

Thank you for any help you can give me
Joe

[RyanHughes]

When he installed the 25HCA336A003 (3 ton unit), did he adjust the airflow on the indoor unit to meet the 3 ton unit's requirements? Air handler is compatible if configured properly. Ductwork seems small to me, but a pro will have to confirm that for you. That could be the problem right there. Did he install the ductwork too?

[joehfd]

the only thing they did was install a3/4 line i believe from the outside unit to the exchanger nothing else was done. they installed everything

[Little NATE]

what tonnage did you have before . like he said maqke sure the air handler is configured right

[DGIO-Not]

Okay. Original unit installed was 2T now you have 3T.

First of all thank you for posting your problem, but also, I am am soooo very sorry you are experiencing this problem.

You have a contractor who did not do a heat load calculation before quoting a job. He is now guessing, but still working with you, so do not give up hop However, if, and this is a supposition on my part, he only replaced the outside unit, you have a mismatched system that eventually will cause damage to system and shorten its life.

I do like Carrier systems, but any system not installed properly or in it's application is going to disappoint.

I know you said you had 12x12 of ductwork in attic, but you did not specify metal duct, externally line, metal duct internally line, or duct board. It does make a difference in material. And are you measuring the inside diameter? (Of Course Not, that is not your job!) The other question, is that ductwork in the attic leaking? Did they discuss this with you or address this issue during installation? The 2T could have been sized properly but the existing ductwork condition not addressed.

Again, I am very sorry you are experiencing this problem. Unfortunately, I can only guess at the reasons why it just isn't right. While I am not sure it would get you far, Carrier does provide direct consumer support and heat/load calcs can be done readily by others not directly related (yes, cost you money. And Yes, should be part of any installation job, but pennies compared to what you will have to put up with in long run--not to mention, codes may require heat load and since you had to get your own, may just reimburse you.)

[joehfd]

First of all thank you for your reply. I went to the dealer on Tuesday and told them there was still a problem, tThe tech came out this morning and he was trying to tell me there was nothing wrong, until I told him there was!, I asked him if the duct sizeing was correct and he asked me if they changed the return flex when they put the 3ton unit in. I told him no. After measureing it he said there was only 12in flex there.

He went out and did some calculations and told me he had to replace it with 16in flex. I kind of suspect they already new that though..so we'll see if it makes a differance, I was told it was probally to small

[DGIO-Not]

Joe,

I am glad they are stepping up and supporting their install. We, in the HVAC industry, have the onus on us as it really doesn't matter what Manufacturer was installed but the Quality of the company doing the installation. While I still have concerns, I am seeing a desire to make it right. I know you do not want to be the one that turns a "good" company into a "better" company, but you are and I do know they are taking notes as this has cost them dearly.

I am still very curious, when they replaced the system the 2nd time, did they replace both the indoor and outdoor unit?

[beshvac]

For carrier equipment the airhandler that he has is the 002 size and variable speed up to 3 tons. so changing the outdoor from 2 to 3 tons the airhandler is still compatible. There must be some other issue.
Indoor design temp is typically 75 degrees. So trying to cool below that especially when outdoor temps have been above typical isn't going to happen. Ductwork is probably the issue, but unknown without looking at it.

But after reading the posts on this system back to january.......Load calculation needed and duct evaluated to the load.

[RyanHughes]

True that the 002 will support the 3 ton outdoor unit. IF the airflow is adjusted accordingly. That may not have been done.

[joehfd]

well they came back on thursday and changed from a 12in flex to a 16 in flex however, they left the same return grill/box there which is 14x30. The plenum coming off the handler is 12x12 im not an expert but something is off here

Joe

[RyanHughes]

12x12 is going to have a hard time moving 3 tons worth of air in my opinion. Quick rule of thumb calculation (for whatever its worth) shows that it would be marginal for 2 tons.

I would talk to them about the 12x12 potentially being too small and the airflow setting on the FV4BNF002 air handler. It will need to be set for +/- 1200 cfm (which is probably its high setting), and it may have a hard time moving that much airflow with your present setup.

Good luck.

[DGIO-Not]

Truth be told, I do not know if HO sold on equipment vs. SEER, EER, HSPF.

I come from the philosphopy that the "Best Test, Rest Guess." This homeowner chose a contractor who is stepping up to the plate, we should help him get his "Value", increase the equipment life and make him feel good about us, the HVAC industry, in general.

This company is following up, he is not left out on his own but he may just need a little info to communicate with them effectively so they can make him a happy, satisfied customer.

BTW: I've always wondered about the professional forums, just not here enough to be a real "ass-et" (meaning pain in the arse or actually helpful.)

[joehfd]

Well first, thanks for the reply..I think I need to get another company here for an opinion

[beenthere]

BTW: I've always wondered about the professional forums, just not here enough to be a real "ass-et" (meaning pain in the arse or actually helpful.)

Its free.
And one helpfull answer at the right time, can save you a lot of head banging.
Or you might save someone else a lot of head banging.

[dash]

Well first, thanks for the reply..I think I need to get another company here for an opinion

Why do you want such a low indoor temp.?What temp. do you want?

Oversizing the system will lead to other issues.

Ducts are very likely too small for a 3 ton,as is the return grille.