high humidity in my house

pecmsg

https://forum.heatinghelp.com/discussion/comment/1862728#Comment_1862728

10 on and 50 off is your issue. Not enough run time to drop the RH.

ratio

https://forum.heatinghelp.com/discussion/comment/1862745#Comment_1862745

Is this the HRV or the AC? Those're fine times for an HRV, but not for the AC.

Also, heat recovery (HRV) or energy recovery (ERV)?

pecmsg

https://forum.heatinghelp.com/discussion/comment/1862747#Comment_1862747

Good question.

plumbergid

outdoor temp and humidity depends on time of day but the low is 13 f and high would be 90f

and rh is anywhere from 50% to 80%.

DCContrarian

https://forum.heatinghelp.com/discussion/comment/1862750#Comment_1862750

Let me clarify the question.

Ventilation will only reduce the humidity indoors if the absolute moisture content of the outside air is lower than the moisture content of the inside air. If the opposite is true, ventilation will increase the humidity indoors.

Relative humidity, as it names implies, is not a measure of absolute moisture content, it's a temperature-dependent measure. The easiest measure to use is dew point. So ventilation only helps reduce humidity when the dew point outside is lower than the dew point inside. In most of the US, in weather where you would be running air conditioning, the outdoor dew point is higher than the indoor dew point.

The reason I asked about the outdoor conditions is that dew point can be calculated from temperature and humidity. What matters is not the range over the course of the year, but at the instant you're running the ventilation.

pedmec

is your system cycling off and on. How long does a cycle run in your system. At a 69 degree return air temperature I don't know how much humidity you expect to remove if your system is cycling off. How low do you set your thermostat. if I was to guess you might have an over-sized system which is great at lowering sensible heat but not much latent heat, which is where all your dehumidification happens.

EBEBRATT-Ed

69 return if the unit is cycling on temp too much it will never lower RH enough. You may need reheat but that is expensive to run a bigger 9thicker coil is better.

I asked this before: With the water and air temps you have it this coil dumping a lot of water? It should be, and is it dumping the water outside the house?

neilc

clarify what's running 10 and 50, the AC needs to be 50 on, and maybe 10 off, to dehumidify,

8 systems running off the chillers, sounds over sized, which is the worst thing you can do with AC / Dehumidification, how big is the place?

this seems to be an "Engineered" system, with bells and whistles, is there by chance a HUMIDIFIER for the winter season? and is it shut off?