Pros & Cons: Humidity Switch for a Fantastic Fan?

wborst wrote:
Check out the Air King DH55 de humidistat from Amazon.com. It is less than $20 and does not use any power. It is just a switch that closes if the relative humidity goes above the set point. Then opens when it falls below the set point.

Mope this helps.

Thanks, that is helpful to me.
Steve

From what I understand, he is wanting a switch to turn the fan on when it become very humid in the TC, not to close the vent.

He has vent covers so it can be used when it is raining or snowing.

He wants to vent out humid air from the RV.

The more accessories the more potential for problems. Would a humidity switch work with a Maxxair cover? How about installing the cover and leave the fan vent open?

Check out the Air King DH55 de humidistat from Amazon.com. It is less than $20 and does not use any power. It is just a switch that closes if the relative humidity goes above the set point. Then opens when it falls below the set point.

Mope this helps.

imgoin4it wrote:
We used to call them a "humidastat". Mounted on the wall like a thermostat. Used them in sensitive computer environmental areas where if the humidity would get too high it would bring on the air conditioning to condense water from the air to lower humidity and if temperature was too cool would bring on reheat to warm the air control temperature. Haven't seen or heard of one in years, but could try heating/air-conditioning supply sources.

They're not uncommon for residential forced hot air heating systems, which tend to dry the air out and so are often equipped with a humidifier. Not all of the humidifier designs allow for controls (many are just wicking material in a pan that's kept filled with water by a float valve), but some do and those will have a humidistat somewhere. I guess other heating systems also dry out the air, but it's harder to incorporate a central humidifier in when there is no ductwork to circulate and distribute the air.

Apparently there are also such things as dehumidistats, which I guess differ mainly by when their contacts are open and closed. Home supply places (and HVAC places) have or at least can order both readily.

imgoin4it wrote:
We used to call them a "humidastat". Mounted on the wall like a thermostat. Used them in sensitive computer environmental areas where if the humidity would get too high it would bring on the air conditioning to condense water from the air to lower humidity and if temperature was too cool would bring on reheat to warm the air control temperature. Haven't seen or heard of one in years, but could try heating/air-conditioning supply sources.

Both of my Fantastic Fans are controlled by wall thermostats.

You can select IN or OUT for fan direction and temp that fan comes on/off.
Fan in 'auto'......vent opens when triggered by t-stat and fan comes on at speed selected.
Then when temp is reached, fan stops and vent closes

I was thinking of something like this.
My suspicion though is that it wouldn't be sensitive enough for controlling moisture in a RV (poorly insulated) though. And, of course, would want it to work on 12 VDC.

Ours have a speed setting and also a temp setting along with rain sensor. Never heard of a "Humidity switch" on a Fantastic Fan.

Ours have a speed setting and also a temp setting along with rain sensor. Never heard of a "Humidity switch" on a Fantastic Fan.

We used to call them a "humidastat". Mounted on the wall like a thermostat. Used them in sensitive computer environmental areas where if the humidity would get too high it would bring on the air conditioning to condense water from the air to lower humidity and if temperature was too cool would bring on reheat to warm the air control temperature. Haven't seen or heard of one in years, but could try heating/air-conditioning supply sources.