carillon

because of your location and summer climate, Trane's 803 or identical HW equivalent is the best choice at the very minimum. The 803 has two stg capability which you need for furnace as well as overcooling feature to handle humidity in cooling mode.

IMO

The equivalent thermostat by Honeywell is the VisionPRO 8000 (TH8000. TH8320, TH8321 vs. TCONT800, TCONT802, TCONT803).

Tiger - don't see location mentioned in the OP (unless you recall it from a previous post).

ryan

OP's location is Tennessee. He is looking to purchase two XL14c Trane gaspak package systems-and as I recall going up in size. He really needs a load calc first and then to check ductwork size if he elects upsizing both systems.

TD

Thanks guys... I just verified that I am going to have the TCONT803 installed for each unit. I read about it and it seems to have some nice features and I'm assuming that it is very compatible with the XL14c units that will be installed.

I am going up a 1/2 ton for each unit that is being replaced. I feel okay that the existing duct work is adequate to handle this increase.

I do have a random question... what is considered to be a typical cycle for cooling in minutes. The reason I ask is because it seems that both of my units run well over 30 minutes to reduce the temperature by 1 degree. Perhaps it's because they are very old and the air they put out is around 65 degrees.

Thanks

Just so I understand better, why do you feel the existing ductwork is adequate to handle any increase? Many systems are undersized in terms of ductwork and already oversized to some extent for cooling. You could be unnecessarily going up in tonnage on ductwork that needs to be examined and repaired/redesigned. I know we're only talking about a half ton here, but it is something to consider for your overall comfort and efficiency. Did the previous two not cool adequately? The task is to find out why.

Thanks ryanhughes... the previous 2 units do not cool adequately. Both units take well over 30 minutes to reduce the temp by 1 degree even on days where temps are in the hi 70s and low 80s.

Last year I had an engineer and HVAC contractor completely redesign the duct work for both systems. Every piece of the previous duct (duct board) was removed and new sheet metal duct installed. At the time this was done I explained to the engineer that I wanted him to consider in his design the possibility of me replacing these units if the redesigned duct work didn't help with the cooling. However, we were hopeful that the new ducts would make a difference since the new design was much better in how it was designed.

It became apparent that the new duct work had helped somewhat but not enough. So instead of trying to fix these old units to see if they could generate air temps cooler than 65 degrees at the register, I've opted to replace them.

The engineer checked our plans from last year and confirmed that I have 16" round mains on my current 3.5 ton and 14" round on my current 2 ton. His opinion when asked by me was that the design had enough capacity to handle the addition 1/2 ton from each unit.