SIGforum.com    Main Page  Hop To Forum Categories  The Lounge    HVAC: High Humidity Indoors (60%)
Page 1 2 

Moderators: Chris Orndorff, LDD
Go
New
Find
Notify
Tools
Reply
  
HVAC: High Humidity Indoors (60%) Login/Join 
Go Vols!
Picture of Oz_Shadow
posted Hide Post
I looked at this as well. I noted two ways some variable speed units address this. The first is slowing the maximum cooling CFM which defaults to 400 per ton to something like 360 cfm per ton. A little less airflow results in a bit more humidity being removed. The second way is with a control on the thermostat that basically does the same thing, often with a couple degrees of overcooling. As an example, if you set it to 75 with a humidity target that is not met it may continue to run to 73 degrees at a lower CFM blower speed to help meet that goal.


Sounds like they are following similar means to do this plus more!
 
Posts: 15493 | Location: SE Michigan | Registered: February 10, 2007Reply With QuoteReport This Post
Center mass,
Armpit level...

Picture of greekfed
posted Hide Post
Possibly s dumb question, but does your smart thermostat have a setting for humidity? Mine, a Lennox, does. Just a thought.


______________________________________________________________________
There is no distinctly native American criminal class... save Congress. - Mark Twain
 
Posts: 3149 | Location: Northern Virginia | Registered: August 12, 2006Reply With QuoteReport This Post
Member
Picture of 4MUL8R
posted Hide Post
My thermostat, the Honeywell 9000, reads both outdoor and indoor humidity but does not have a control circuit or RH setpoint feature.

The humidity is now over 60% regularly, even during the evening. SWMBO cannot survive in the frozen tundra of 70 F, to simulate overcooling. I may be able to try 68 F next week when I work from home and she is away.


NRA Life Member
 
Posts: 3227 | Location: Commonwealth of Virginia | Registered: January 15, 2007Reply With QuoteReport This Post
Go Vols!
Picture of Oz_Shadow
posted Hide Post
You may just have to get a stand alone dehumidifier if the installer can’t get the system dialed in. Like others mentioned it may be too large.
 
Posts: 15493 | Location: SE Michigan | Registered: February 10, 2007Reply With QuoteReport This Post
Only the strong survive
Picture of 41
posted Hide Post
Window A/C's have a drain hole to let the condensation water out. The hole can get plugged and the humidity will raise to 90 percent.

The same thing can happen to your indoor units. My heat pump unit got plugged and over flowed onto the air filter.




41
 
Posts: 10196 | Location: Herndon, VA | Registered: June 11, 2009Reply With QuoteReport This Post
Member
posted Hide Post
quote:
Originally posted by 4MUL8R:
My thermostat, the Honeywell 9000, reads both outdoor and indoor humidity but does not have a control circuit or RH setpoint feature.

The humidity is now over 60% regularly, even during the evening. SWMBO cannot survive in the frozen tundra of 70 F, to simulate overcooling. I may be able to try 68 F next week when I work from home and she is away.


If your thermostat has a calibrate function, turn it up a degree or 2, so it reads 72 when it's actually 70 inside. I bet she won't notice and/or you can explain it away. I survived like that for 5+ years until a fucking baby monitor showed the temp in the kids room.
 
Posts: 2570 | Location: IN | Registered: January 12, 2007Reply With QuoteReport This Post
Savor the limelight
posted Hide Post
I'm not an expert, but let's look at this step by step.

If the AC is shutting off because it's reaching the temp set on the thermostat before reaching your desired humidity, then you are generating too much humidity, your AC is oversized, or both.

The humidity is coming from somewhere.

What is the humidity outside? Is it lower, higher or the same as the humidity inside?

If it's lower outside than inside or the same, maybe additional venting is called for in locations where humidity is being created. Bathrooms and kitchen.

If it's higher outside than inside, the above may still apply, but maybe you need to take a look at where there could be outside air coming into your home. Vapor barrier in the crawl space has been suggested as one place to look. Maybe there are others.

The AC has to be running to dehumdify.

What are the run times and cycle times of your AC units?

Do they run 5 minutes on and 10 minutes off or 20 minutes on and 10 minutes off, for example?

Your AC units are ductless mini-splits, correct? You haven't mentioned how these are installed in relation to the layout of the house. Do you have ducting and an air handler for heating? If so, could you run just one AC unit and run the air handler at the same time? This would circulate the air inside the house while the one AC unit pulled moisture out of the air with a longer run time.
 
Posts: 4929 | Location: SWFL | Registered: October 10, 2007Reply With QuoteReport This Post
Member
posted Hide Post
quote:
Originally posted by Excam_Man:
Did they do a load calculation?

Is it uncomfortable? Meaning, does it feel any different then BEFORE the new systems?


You come looking for solutions, yet you don't answer questions... ? Confused




 
Posts: 7860 | Registered: October 15, 2008Reply With QuoteReport This Post
Member
posted Hide Post
quote:
Originally posted by trapper189:

Your AC units are ductless mini-splits, correct?


That will be a negative.




 
Posts: 7860 | Registered: October 15, 2008Reply With QuoteReport This Post
  Powered by Social Strata Page 1 2  
 

SIGforum.com    Main Page  Hop To Forum Categories  The Lounge    HVAC: High Humidity Indoors (60%)

© SIGforum 2019