DIY Home Improvement Forum banner

1 - 16 of 16 Posts

·
Registered
Joined
·
28 Posts
Discussion Starter · #1 ·
Dear DIYers,

Trying to figure out the best way to go...so here goes.

Back in April, my wife and I had a air quality test done in our new home we bought in January. The house was built in 2007. The air quality test said we had high particles, high co2, and high relative humidity...around 64% on average. Also, i have sinus issues that make me more susceptible to these issues....something called vasomotor rhinitis.

So after some research I decided to seal up the spaces in between my supply vents and the sheet rock because I came to the conclusion I was pulling in attic air along with attic particles. That seems to have helped dramatically.

However, I'm not convinced that I have solved all my problems. The humidity is still around 55%.... Kinda high from what I can tell. The particles seem to be lower but sometimes they seem to be high. Don't know anything about co2 levels. I'm not really wanting to pay $200 everytime I want to get an air quality check. I did buy a $10 hygrometer which gives me my humidity readings. The house has carpet in most of the house...thought that might cause some of the high particles...but air quality guy said that if that was the case the particles would've gotten higher when we got home and started walking around. But they were high a lot of other times.

I have talked this out a little with some hvac guys here.
http://hvac-talk.com/vbb/showthread.php?t=1114061

There was some speculation about doing a whole home dehumidifer to dehumidify the air and bring in some fresh air from outside. But called a guy yesterday and he said I shouldn't need that in Texas.

I thought I would see what some DIYers/ homeowners that weren't professional hvac guys would say.
 

·
Banned
Joined
·
17,158 Posts
Are you sure it isn't Carbon Monoxide. Carbon Dioxide is what you exhale. If you have hogh CO, it is most likely coming from appliances, due to the home being too well sealed.
 

·
Registered
Joined
·
28 Posts
Discussion Starter · #3 ·
Actually...carbon monoxide was the only good reading from the air quality test. I have all electric appliances. How do I know if the house is too tight?
 

·
Banned
Joined
·
17,158 Posts
Actually...carbon monoxide was the only good reading from the air quality test. I have all electric appliances. How do I know if the house is too tight?
High humidity, and high co2 levels as you stated. There is not enough air exchange from indoor to outdoor air. Way too tight for not only the home, but the inhabitants.
 

·
Registered
Joined
·
28 Posts
Discussion Starter · #5 ·
So...far from experts...I've got I need a whole house dehumidifier. I've also gotten that I need to do a load calculation to make sure my unit isn't too big for my house....I've also gotten I need to do a door blower test. I'm really unsure about which way to go.
 

·
Registered
Joined
·
28 Posts
Discussion Starter · #6 ·
If the unit is too big....i was told it could be causing the high humidity. I cam here to this forum to get some wisdom from some homeowners who mighta have experienced the same thing hopefully from an identical context....maybe even an identical context.
 

·
Banned
Joined
·
17,158 Posts
55% humidity is fine. You really do not want it too low, or you start having problems on the other side of the curve. Still missing a lot to the story. What do you mean by oversized hvac system? Every hvac system is going to be either undersized or oversized, depending on who did the install.

Again, need more info, due to really confusing as to what you are getting at, other than you are stating that you have high Carbon Dioxide levels, which makes no sense as to who or how came up with that, along with high particles of what.
 

·
Administrator
Joined
·
41,559 Posts
55% is high, leaves little safety. My place is seldom at 50%, usually 48% or less, and feels much more comfortatable then 50%plus.
 

·
Registered
Joined
·
28 Posts
Discussion Starter · #10 ·
Well

I have been told that my unit is too big for my house....3 ton unit for 1690 square feet....a sizable portion of that is vaulted ceilings. So since it is too big...it gets temperature down before it gets humidity down. I have also been told that my unit is fine by a local guy who has worked on other homes here in my neighborhood along with my groin laws house.


I'm not real comfortable with 55%...because it is the low end of the average...keep in mind that it is 55% at 70 degrees. If it was 55 % at 72 or 73. I would be cool....no pun intended. Im kinda shooting for 45% to 53%.

The readings I gave are from an air quality test done in April. I have sealed the cracks on all the supply vents. The particles are both chemical and allergen pollutants.


I think I have decided to go with another return in a part of my house that is off by itself pretty far away from the only return I have. 25x20x1 going to an 18" flex. Theoretically I think I have enough return...but the part of my house that seems to be much worse on symptoms is off away from my return. It also seems to be hotter over on that side of the house.
 

·
Banned
Joined
·
17,158 Posts
Again, who is telling you that your unit is too big for the home. Just because it is 1690 feet? Every structure is different, and the home next door to yours may get by fine with a 2ton, the next one over on the next block that is the same size as yours, may need a 2.5 ton. Only way to find out, is to have a proper Manual J done to figure if it is sized appropiately, or oversized. Taking someones opinion from the web, is like going to your mechanic and asking them how to perform open heart surgery, or set a broken bone.

As for chemical & allergen particulates, every house is going to have this stuff in it, it is common due to building materials, furniture, common household cleansers, etc.

As for the duct work, you will need to get someone to do a Manual D to find out if it is correctly sized or not.
 

·
Registered
Joined
·
28 Posts
Discussion Starter · #12 ·
One of the hvac guys at hvac-talk.com. I just gave him the cubic footage of the house. I have had a different hvac guy who has worked with houses in my neighborhood tell me it is ok for my house. He simply says I should add an extra return in the part of my house I described. He saysi just need to circulate more air...lit will bring down humidity...I plan to talk to him about co2 levels.
 

·
Registered
Joined
·
28 Posts
Discussion Starter · #13 ·
The reason I labor this point is because I am borderline asthma due to a condition known as vasomotor rhinitis. So I am more sensitive to this stuff than most. No allergies (been tested 3 times) but rhinitis.
 

·
Registered
Joined
·
2,362 Posts
What's the humidity in the house now that summer is here,still over 50%? If so then the AC is too big. High CO2 shows there's not enough outside air exchanges. One product that I've seen on the net that will take care of both problems without replacing the AC is the ultra aire whole house ventilating dehumidifier.
 

·
Banned
Joined
·
17,158 Posts
Marty, I hit on no outside air exchange prev. As for the high humidity, due to no air exchange, betting that it raises anytime the dishwasher is running, and people are taking showers, or the dryer is running.
 

·
I'm Your Huckleberry
Joined
·
5,884 Posts
What kind of unit inside, gas or electric? Can the blower speed be reduced especially if on high during cool. High speed is the usual speed for cool. Turn it down from hi to med-hi. This will make the air slightly warmer and less velocity (not as powerful coming out of the registers) while running longer and thus dehumidifying the home in the process which at this time is your only concern I'm assuming..

Unless you are made of money I'd try that first, then a whole home dehumidifer or even a combination of both.

Done.
 
1 - 16 of 16 Posts
Top