Coils sized properly

[Richard W. Washington]

I had a carrier indoor coil model nbr LH42/62E9C which I know to be a 3.5 ton.
The outside condenser was a model nbr with a 47 in it (did not jot down the whole model br) which I bellieve to be just shy of a 4 ton. Is it going to be a problem that the indoor coil seems to be smaller than the outdoor unit?
this is a new home.

[rspermo]

Coils and condensers should be matched according to the manufacturer's requirements. The only real way to know if the coil and condenser match is to ask the manufacturer.

[Charley L. Bottger]

Several things come into play the indoor blower CFM the amount of supply air drops the distance of the supply runs. One cannot just make a blanket statement that it is under sized. A good many MFG would allow 1/2 ton over and 1/2 ton under between the condenser and the A-coil

[Richard W. Washington]

Thanks Charley. I did not know for sure so just left it alone. It was under 60 outside during the inspection so did not operate it anyhow.

[Jim Hime]

A lot of the numbers you see may no longer be btu specific if you are attempting to size a system. They can fit a range of coils and condensers (and visa versa) sizing depending on what the designer is targeting (more SEER, more dehumidification, more air flow through coil, more "cold", etc.). In the real world we generally deal with production builders and at least there is a common denominator, the ARI.

You can check out the ARI link below -

http://www.ahridirectory.org/ahridir...ages/home.aspx

This won't work for discontinued equipment.

[Richard Webb]

Mr.Washington, I see you are from Katy. My wife has family there. Years ago it was quite common for knowledgable HVAC contractors to install smaller coils near the coast. It causes the indoor coil to operate with a lower temperarure, thereby giveing added amount of moisture removal. If done right it will not cause icing of the coil due to higher latent heat values. Currently, the coils are much larger but operate with higher coil temps. The larger area offsets the lower humidity removal of a warmer coil. Use of a thermo-expansion valve on the larger coil really helps as the coil would then be roughly the same temp. all over as opposed to a fixed orifice which can lead to part of the coil not haveing much cooling effect.