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JohnDavid
high humidity problem

I have a high humidity problem which is quite bad on the 2nd floor. I bought a hygrometer and a dehumidifier in an attempt to locate the problem. The hygrometer has read up to 80% before I got the dehumidifier. I recently had the heat pumps serviced by my AC service contract. The technician said the 2nd floor unit was OK. He said the 1st floor unit was functioning OK but he drain pipe was not sloped properly. Said I should get a pump to get rid of any water that may back up in the unit because of the drain slope. The drain was covered with dirt but I cleared it away. It drains but noticeably slower than the 2nd floor unit. My dehumidifier is 45 pint and I empty it daily! Called several house inspectors but they say the problem is almost certainly with the heat pumps. I have been in the crawlspace to see if I could find anything obviously wrong. On 2-3 occasions I have seen small puddles on top of the plastic ground cover. Probably only 2-4 ounces. Not sure where it came from. I looked around in the attic area and could not find any leaks.

JohnDavid
Re: high humidity problem

From research on the internet I see that the plastic vapor barrier should be at least 6 mil, black, overlapped, sealed, and cover the entire crawl space. The vapor barrier in my crawl space is maybe 4 mil, clear, gapped, not sealed to walls or supports, and does not cover the entire crawl space. I thought what I had was OK since the house inspector did not tell me otherwise. I calculate I need enough plastic to cover 1500 square feet, including 12 inch overlap at the seams. Question, should I pull out the plastic that is already down there first? It’s thin, cracked, ripped and does not cover the entire space any way. If anyone has any other suggestions let me know. I plan to get started within the week. It will take me a couple of days and lots on sweat to finish I guess.

bsum1
Re: high humidity problem
Quote:

I have been in the crawlspace to see if I could find anything obviously wrong. On 2-3 occasions I have seen small puddles on top of the plastic ground cover. Probably only 2-4 ounces. Not sure where it came from. I looked around in the attic area and could not find any leaks.

Is this crawl space under the house?
I'm confused why you would check the attic if there was some moisture in the crawl space that may be under the house?
Also I'm confused why the humidity would be an issue on the second floor and not on the first floor if the crawl space under the house was damp?

Quote:

Question, should I pull out the plastic that is already down there first? It’s thin, cracked, ripped and does not cover the entire space any way.

this would be a good idea to remove the ratty stuff and lay down the 6 mil. The one thing that I've learned from this forum is to use the house wrap tape to seal the seams of the plastic.

Marjorie
Re: high humidity problem

I realize it's kind of a dumb question... but do you have a whole house (or single story) humidifier that was left in the 'on' position? (so instead of blowing dry air, it's blowing humidified air)

JohnDavid
Re: high humidity problem
bsum1 wrote:

Is this crawl space under the house?
I'm confused why you would check the attic if there was some moisture in the crawl space that may be under the house?
Also I'm confused why the humidity would be an issue on the second floor and not on the first floor if the crawl space under the house was damp?

this would be a good idea to remove the ratty stuff and lay down the 6 mil. The one thing that I've learned from this forum is to use the house wrap tape to seal the seams of the plastic.

Sorry, gues I was a little confusing there. I checked the attic to see if there was maybe the roof was leaking and contributing to the humidity. The humidity is an issue in the whole house. It is just so much worse on the second floor. I can only assume it is so bad up there because heat rises.

JohnDavid
Re: high humidity problem
Marjorie wrote:

I realize it's kind of a dumb question... but do you have a whole house (or single story) humidifier that was left in the 'on' position? (so instead of blowing dry air, it's blowing humidified air)

I'm not sure what you mean by a "whole house" humidifier. I have a LG LHD45EL 45-pint dehumidifier. I have it upstairs and leave it in the -on- position constantly. I have to empty it daily. I don't have a dehumidifier downstairs.

Marjorie
Re: high humidity problem

What I was referring to is a whole house humidifier... it is connected to the furnace / blower, and in the winter is fabulous for eliminating the dry-air miseries because it puts humidity into the air. I had one in my old house, it was basically a big pad connected to the water supply (with a dial to set it). The warm air would blow over it and so put humidity thoughout the house. One year I was still running the furnace when the heating/cooling guys came out to service the air conditioner, and I told him to leave the humidifier on (they usualy turned it off and cleaned everything).
Then when summer came, i forgot about that, and couldn't get the inside of my house cool and dry and comfortable. Finally called 'em to talk about the problem, the tech remembered we'd left it on, and told me. So I turned off the humidifier and then the A/C could dry out the air. d.u.h/ :rolleyes:

Long story. sorry. I think you must not have a whole house humidifier or you'd know it.

Good luck with your humidity problem.

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