Input on AC Only System Replacement

[CardiffGiant11]

Hi,
I live in Central CT and we have a 5 zone hydronic heating system and a separate forced air central A/C only system. Heating system was done in 2015 but the A/C is original to the house (1993). It wasn't blowing cold and tech said massively low on Freon and since new Freon can't be produced the cost to recharge plus the fact there is a leak somewhere is telling us time to replace it. House is 2880 sq feet, new windows, pretty well insulated. Also has finished lower level that does not have ducts since it stays cool so only heat is needed there.

Air handler is in our attic but duct work is well insulated. So far, two different contractors have come over. One was recommended by a friend and has great reviews, other is the company that did our new heating system and they were and have continued to be great. Have two more coming tomorrow.

First contractor quoted 4 options of which we are only considering two.

Amana 4 ton 16 seer Condensor AVPTC61D14 with Variable Speed Air Handler SX160481 or Goodman 4 ton 16 seer Condenser GSX160481 with variable speed air handler AVPTC48D14. He would plan on reusing the existing line set that is in our Chase.

Second contractor quoted 3 options of which we are considering two.

American Standard 4 ton Condenser 15 seer 4A7A4048L1000, Variable Speed Air Handler TEM4AOC42H41.


Ameristar 4 ton 13 seer Condensor M4AC03048B1000N, with variable speed air handler M4AH3048B1000A.

For both options, he would run a new lineset and close up the hole that would be left in the existing chase by the old lineset. I've noticed the old lineset would sweat in the summer sometimes so wondering if that issue would persist with a new set.

At any rate, Contractor #2 was the owner, where as #1 was a sales guy. Also going for it Contractor #2 did our heating and was great. So strongly leaning toward him. I did some research and see that Ameristar is owned by Ingersol Rand (same parent as American Standard) but is made in China. However, both warranties are the same and the anecdotal evidence I found here seems like they are good units.

Any thoughts? Again, we are only replacing because ours is dying not because of a desire to be more efficient etc. I figure anything we get will be quieter and more efficient and given the part of the country we live in and how short the cooling season is (3 months and not even a full 3 months depending on weather), not sure the gains in efficiency alone are worth it.

Thanks for any input

[HVAC_Marc]

Hi,
I live in Central CT and we have a 5 zone hydronic heating system and a separate forced air central A/C only system. Heating system was done in 2015 but the A/C is original to the house (1993). It wasn't blowing cold and tech said massively low on Freon and since new Freon can't be produced the cost to recharge plus the fact there is a leak somewhere is telling us time to replace it.

New r22 is being made. It's not yet massively expensive.

Here's option 5 - find the leak and fix it. Even a new coil and recharge will be far less than a new system. Plus, a replacement refrigerant like 407C could be used.

Sounds like you have sales techs there. If the system has been durable and has had low or no repair costs then I'm all for fixing it.

[CardiffGiant11]

New r22 is being made. It's not yet massively expensive.

Here's option 5 - find the leak and fix it. Even a new coil and recharge will be far less than a new system. Plus, a replacement refrigerant like 407C could be used.

Sounds like you have sales techs there. If the system has been durable and has had low or no repair costs then I'm all for fixing it.

thanks the condenser is in pretty rough shape physically and even when we moved in in 2015, it’s always struggled to get the air temperature below 72 and rarely could get it below 70. so that probably helps the decision

[HVAC_Marc]

I doubt the new system will fix that. It may be undersized ducts or a lack of mandatory duct insulation.

[BaldLoonie]

The TEM4-42 is a high efficiency blower motor but not variable speed. Why air handler smaller than A/C?

Not sure on the Ameristar air handler. It didn't say what motor it had. Unless money is a big issue, I'd want genuine American Standard/Trane not a Chinese cheapo.

How did they establish 4 tons for that space? Seems pretty excessive for a cooler part of the country and a shorter cooling season.

[CardiffGiant11]

Hi thanks for the input i will have to double check on the model number for the American Standard air handler possible typo on my part. as for the 4 ton sizing, existing unit is 4 ton and based on cooled sq ft (2880 since the lower level is an additional 600 that is not cooled) is how the sizing was factored in i believe. does that sound like too big of a unit based on what i’m describing? the house sits north south and has tons of windows and two skylights so not sure if that factored in as well.

as for the ameristar vs am standard, thanks. the ameristar is considerably less (~16%) but sounds like that would be money well spent.

[rider77]

Sizing isn’t done via square footage. It’s done via manual j/s/d calculations.
Here’s a free example of a manual J-

www.loadcalc.net

[Freezeking2000]

I do not like the idea of China over American made Amana.

Sent from my Pixel XL using Tapatalk

[udarrell]

They all appear to be oversizing the A/C plus offing high cost equipment you don't need in your short season cooling climate.

The reason the existing, I'm guessing, 4-Ton didn't cool to 70°F is probably due to an inadequately sized duct system & too small a filter area; resulting in inadequate airflow & lack of an adequate heatload on the evaporator coil. (*poor design engineering)

For your area, I would not go above a much lower cost 3.5-Ton A/C & 14-SEER which would match the airhandler tonnage. When the A/C gets indoor humidity below 50% you should be comfortable at 75°F, not 70°F.

Summer design at Hartford, CT is 88°F dry bulb, 75°F wet bulb for 54.6% relative humidity, so the system needs a lot of runtime to dehumidify sufficiently...