Oversized Unit Options?

[rsisson]

When we originally put in our AC unit several years ago it was sized right for our old drafty, uninsulated house...

We have replaced windows, replaced doors, added many inches of insulation in the attic, caulked, and caulked, and caulked...
You get the idea...

Our unit is now oversized and we need to crank the temperature down too low to get the humidity out...

Are there any options rather than replacing the units, as we will continue to replace windows and doors over the next few years...

I was hoping for an industrial speed control for the compressor, or a bypass or...

The system is a Unico High pressure system with a Carrier 38TXA060320 Puron Compressor.

[beenthere]

Until your done making improvements, get a portable dehumidifier.

Nothing can be done to your system since its a HV.

After your done, you will need to have a load calc done, and the proper sized indoor and outdoor unit installed.

[jacob perkins]

Originally posted by rsisson

I was hoping for an industrial speed control for the compressor, or a bypass or...

Or bring in fresh air.

[dan sw fl]

Originally posted by beenthere
Nothing can be done to your system since its a HV.

This issue of a temporary or long term improvement should be
referred directly to UNICO.

1-800-527-0896.

http://www.unicosystem.com/CustomHom...ctByDesign.asp

A significant sized by-pass may help ...
but to WHAT Degree is the bigger question for H.V.?

[Edited by dan sw fl on 06-05-2005 at 08:14 PM]

[teddy bear]

Bring in fresh air? How will that solve the humidity problem unless you can bring the air in form Arizona. I agree with fresh air to purge pollutants and replace oxygen.
What size should the a/c be to keep the home dry with 70^F outdoors with rain for a week? It must be Zero tons but run all the time, right!
Seriously, you're decreasing air infiltration and heat gain from outdoors which is good. For real indoor air quality, consider fresh air ventilation and real humidity control from a whole house ventilating dehumidifier. This provides absolute humidity control totally independent of the a/c load. +78^F with <45%RH is comfortable, saves electricity, and minimizes the condesation of moisture in walls, ducts, and on grills.
Your oversized a/c allows using thermastat setup when the home is not occuppied. This has potiential to save a lot of energy. In addition to moisture condensation on cold surfaces, cooling with a/c removes <2 pints per KW. The high efficiency dehus like Ultra-Aires remove 5 pints per KW.
Keep your a/c and get a dehumidifier! Nobody can size an a/c to provide humidity control for the wet, cool weather. If so, get it money back in writing.

[biscuitnt]

I think what he means by the fresh being introduced is keep the unit from short cycling and not having time to remove any moisture. the outside air will be humid but the larger unit will dry it out, the only thing is that the amount will need to be damper controlled and appropriate exhaust/relief measures taken to remove the conditioned air from the space. Then you are using the outside air as make-up air.

The whole house humidity control sounds like the best option for now, but if the system is that oversized, it will need to be replaced.

Energy bills will suffer though!.

[Edited by biscuitnt on 06-06-2005 at 02:01 PM]