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Old 10-23-2024, 05:47 AM
retiredguy123 retiredguy123 is online now
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Quote:
Originally Posted by ithos View Post
Something is not right. Dehumidification mode should always maintain temperature at setpoint. The duct heaters should cycle to maintain constant temperature.

Cooling only will not help since relative humidity is based on two factors. The amount of vapor in the air and the dry bulb temperature. The cooling stays on longer so that water vapor is removed in the chill water coil. It also lowers the dry bulb temperature. Reheat brings the dry bulb temperature back to setpoint.

There are several different definitions of humidity. RH is it is the amount of water vapor present in air expressed as a percentage (%RH) of the amount needed to achieve saturation at the same temperature.

Saturation is when the air can not hold any more water vapor at a given temperature and pressure and condensation on surfaces begins.
My system, and many others in The Villages, do not have a reheat function. So, they are not true dehumidifiers. They reduce humidity by "overcooling" the house to reduce humidity. So, if you set the temperature at 78 degrees, and the humidity at 60 percent, the system will cool the house down to about 75 degrees when the humidity rises above 60 percent. This is a compromise that works fine for snowbirds who want to save a few dollars on electricity by controlling the humidity with a higher than desired temperature. But, if you are living in the house, you want to maintain a comfortable temperature that stays at the setpoint. That is why I turn off the dehumidify feature on the thermostat. It is an optional feature. If you want to control both the temperature and the humidity, you need a true dehumidifier with a reheat function.