New XL20i owner, have concerns

[TheMark]

I have 39%RH at 76F

I re-insulated my attic last year with R30, also had a solar barrier installed up there. I will get some pictures taken of the control board and post them.

Is there anything special I need to know about removing the panel on the front besides that it will turn off? I've seen one of the installers struggle a bit with getting it re-installed.

Thanks again

[SoFlaDave]

Any idea what the Air Handler model is? Should be a TAM7 or TAM8

[motoguy128]

I have 39%RH at 76F

I re-insulated my attic last year with R30, also had a solar barrier installed up there. I will get some pictures taken of the control board and post them.

Is there anything special I need to know about removing the panel on the front besides that it will turn off? I've seen one of the installers struggle a bit with getting it re-installed.

Thanks again

39%RH @ 76F isn't too bad. That's close to what my house averages on hotter days before bedtime. Right now it's 77F, 34%RH downstairs right now, 74F 45%RH upstairs. A single story home would be an average of those since it doesn't experience reverse stack effect (air leaks in upstairs, leaks out downstairs).

I'm thinking your system for the most part is behaving normally. But it's worth checking to see what the dip switches are set to.

Also, what thermostat do you have? IF it's communicating, I think the airflow setting might be set at the thermosat and will override the dip switches.

[TheMark]

Thermostat and air handler model.

This is a 2 story house, the thermostat is on the second floor

[TheMark]

..deleted, wrong post

Do I still need pictures of the inside of the air handler?

[teddy bear]

39%RH @ 76F isn't too bad. That's close to what my house averages on hotter days before bedtime. Right now it's 77F, 34%RH downstairs right now, 74F 45%RH upstairs. A single story home would be an average of those since it doesn't experience reverse stack effect (air leaks in upstairs, leaks out downstairs).

I'm thinking your system for the most part is behaving normally. But it's worth checking to see what the dip switches are set to.

Also, what thermostat do you have? IF it's communicating, I think the airflow setting might be set at the thermosat and will override the dip switches.

The other issue is the "lack of fresh air change" in these home that have these very low dew points. Healthy homes should have a fresh air change in 4-5 hours minimum when occupied. How can you tell how much fresh air is infiltrating your home? If the a/c is off for 4-5 hours with an air change fresh air, your indoor dew point will increase 50-70% of the outdoor dew point. Very dry homes with high outdoor dew points indicates a properly set-up a/c without adequate fresh air.
I suggest that all very dry homes add an air of fresh air in 4 hours before celebrating. Typically exhausting 100 cfm for an extended time to confirm the proper fresh air. Your a/c will easily handle the load during hot weather. But during low/no cooling load conditions, the indoor dew point track toward the outdoor dew point. In addition, the moisture from the occupants will add to the indoor dew point. Fresh air change purges indoor pollutants and renews oxygen.
100 cfm of fresh air with a +70^F dew points is a 4-5 lbs. moisture load per hour. This is an opportunity to learn some of the finer points of indoor air quality and humidity control.
Regards TB

[TheMark]

Here's some pics of the slab, its ~95F outside and sunny... hasn't rained in 24hrs.