"Bob M." wrote in message
...
About 800 sq ft Cape Cod style house with forced warm air heat. Added
2-ton
York central A/C in 1989. Due to plenum shape, they put in a horizontal
coil
rather than an A-shaped coil. Worked well once I blew insulation into the
house. Always felt very comfortable.

2 tons on 800SF...wow..



Replaced the furnace in 2000 with a Lennox gas unit, and they installed a
new Lennox A-shaped coil in the output plenum. Same 2-ton capacity. Same
York compressor unit. The system will cool the house down quite nicely,
but
the humidity seems uncomfortably high at times, like over 50% even with
the
temp down to 74F. On days when it's in the mid 90s the system will bring
the
house down to the mid 70s and keep it there, cycling on and off as need
be.
The condensation pump runs, but not nearly as often as it did with the old
setup. Cold air comes out of the ducts at about 58 degrees, so the system
seems adequate for "cooling" purposes.

The fan speed was factory set to the highest speed.

Bingo..

Problem.

That 3 speed fan, isnt to go play with, its to allow for duct issues and
blower curves...

I'm wondering: could
such a fast fan speed be literally blowing the air and moisture right off
the coolihg coil, and not giving it a chance to condense the moisture so
it
drains out? I can lower the fan speed (I have 4 to choose from) but before
I
get into that, I wanted to at least see if my theory made sense. I figure
if
the air moves slower across the coil, the moisture will condense and drip
down and out. Never had this problem with the old horizontal coil.

Partially right..its not allowing the air enough time on the coil



Also, one of my upstairs rooms has its own 5000 BTU window A/C. When I run
that unit to cool the room down to 74, then leave it to go back into the
main floor, there's a noticeable increase in humidity and the room feels
clammy and uncomfortable. It's this comparison that's got me thinking the
central system isn't removing the humidity like it used to.

Any thoughts or suggestions? Is my analysis sound? I don't see any
moisture
around the furnace, so I'm fairly sure the condensed water is going where
it's supposed to. When the thermostat shuts the system off, the condensate
pump usually comes on a few seconds later to pump the water out. That's
why
I almost think it's saving it until the fan slows down or stops.

Slow the fan down, however when you do this, the current charge in the unit
may not be enough...
I would type more on this, but my helper took my fingertip off in an
accident today, and typin is real fun right now..


Thanks.
Bob M.