4 ton Trane Xli Compressor sizes

[Rudyhvac]

Hello HVAC Guys!
I am currently interested in a Trane 4 ton Xl19i heat pump. I am curious regarding the sizes of the dual compressors contained in this condenser unit. The literature does not tell me the sizes. My house has been sized for 3.5 ton, the Xl19i comes in 2.4,3,4,& 5 ton sizes.
I think it may be possible for the 3 ton unit to be sufficient as well depending on the compressor sizes. I would like more information before I talk with a contractor. I Want to be knowldegable when talking with the s0-called experts. Your assistance is appreciated.

RudyHvac

[BaldLoonie]

The 19i has 2 compressors, full size and 1/2 size. They don't both run at once. So if you need 3.5 tons, better go the 4 ton unit. 2 things: Even though it is called 19, SEER on the bigger units runs 14-16. Also, there's been some reliability problems with compressor failures.

You might instead consider the 16i which has a 2 stage unloading scroll instead of the old recips. SEER is about the same as the 19 despite the model # confusion.

[Rudyhvac]

Baldloonie,
Thanks for the timely response. Good HVAC information is important. By the way what do you think about running a heat pump at 350cfm versus 400cfm?

RUDYHVAC

[BaldLoonie]

Less air means warmer air in the winter and drier air in the summer. Some of the Carrier air handlers in comfort mode move even less than 350/ton. Of course, efficiency takes a dive as the heat jumps up!