Central air return filter grate size is just barely too small?

[Shophound]

Ducts can "look" sealed, but until you test them for leakage, there is not a consistent way to verify how tight they are via eyeballing.

90° elbows, such as shown in your photo of the return with the filter removed, are notorious for leaking around all of those "ribs" you see on that elbow. Seldom are they sealed during installation; if any sealing on ductwork is done at all it is typically where the flex connects to collars, elbows, plenums, etc. Which is good when they do that, of course. But if the elbow joints (ribs) are not also sealed, you can well be pulling attic air into the return ducting and distributing same, unfiltered, through the entire house.

Two questions about your house, if I may:

• Are there pull-down stairs to the attic inside the house? If so, is there any weatherstripping where the hatch meets the ceiling?
• Do you have any recessed light fixtures in the ceiling that penetrate into the attic? When you are in the attic, can you see light (given the fixture is not illuminated and any attic light is also off) entering the attic from the house below through the fixtures (provided they are not buried in insulation)?

I mention these two items (which are only two among several related matters) that could be contributing to your health problems. The overall idea is to get an attic as isolated from the house as possible. Many builders have not yet grasped why this is so important, as in spite of technological advances, we keep building houses very similar to how they were made fifty years ago. Only styling and size has changed, with perhaps modest technical gains and technique changes in construction, such as better windows, composite materials, etc.

[allergyman]

Ducts can "look" sealed, but until you test them for leakage, there is not a consistent way to verify how tight they are via eyeballing.

90° elbows, such as shown in your photo of the return with the filter removed, are notorious for leaking around all of those "ribs" you see on that elbow. Seldom are they sealed during installation; if any sealing on ductwork is done at all it is typically where the flex connects to collars, elbows, plenums, etc. Which is good when they do that, of course. But if the elbow joints (ribs) are not also sealed, you can well be pulling attic air into the return ducting and distributing same, unfiltered, through the entire house.

Two questions about your house, if I may:

• Are there pull-down stairs to the attic inside the house? If so, is there any weatherstripping where the hatch meets the ceiling?
• Do you have any recessed light fixtures in the ceiling that penetrate into the attic? When you are in the attic, can you see light (given the fixture is not illuminated and any attic light is also off) entering the attic from the house below through the fixtures (provided they are not buried in insulation)?

I mention these two items (which are only two among several related matters) that could be contributing to your health problems. The overall idea is to get an attic as isolated from the house as possible. Many builders have not yet grasped why this is so important, as in spite of technological advances, we keep building houses very similar to how they were made fifty years ago. Only styling and size has changed, with perhaps modest technical gains and technique changes in construction, such as better windows, composite materials, etc.

The stairs into the attic are actually on the ceiling of the garage, which is a good thing because the hinge is ever so slightly crooked that the "door" doesn't close flush with the frame.

There are quite a few recessed lights in the home. At least 5 in the main living area/kitchen, and then another 3 in the master bathroom. I have not checked if these are sealed well because there is quite a bit of insulation in the attic covering up the recessed cans. I'm honestly not even sure if the lights are the style that can be buried in insulation, and it's something I need to check out some day to know they're not a fire hazard.

[Shophound]

Yes, that's a good thing to check..."can" lights that are compatible with insulation surrounding them should be labled "IC", which means "insulation contact". If it says "ICAT", that's really good, in that it means "insulation contact air tight". Which is what you really want up there.

[54regcab]

OG&E will do an energy Audit for $50 which includes a HVAC system checkup.
If you are concerned about utility bills look into Smarthours.

[allergyman]

OG&E will do an energy Audit for $50 which includes a HVAC system checkup.
If you are concerned about utility bills look into Smarthours.

Funny you mentioned this. I actually work for OG&E so I hear about this stuff quite often.

The only thing is I don't have OG&E as my utility provider (I'm down south where we have OK COOP), so I need to check if I still qualify.

[54regcab]

Funny you mentioned this. I actually work for OG&E so I hear about this stuff quite often.

The only thing is I don't have OG&E as my utility provider (I'm down south where we have OK COOP), so I need to check if I still qualify.

I doubt it, but you work there so you can find out for sure

[allergyman]

One last question for anyone still reading this. I really do appreciate all the responses so far.

Comparing my current home to the last one, I am noticing that I am able to set the thermostat in this house much higher and remain just as comfortable.

What was 77*F AC in the last home is probably equivalent to 80*F in this house. I have 2 independent thermometers I'm using to gauge the accuracy of the wall mounted Carrier-branded thermostat and the temperature is true.

Would this simply be a matter of humidity? The last house had an AirCycler hooked up to the AHU and the fan would circulate on its own clock...maybe every 15 minutes regardless of the system being on or not. I think this was part of the design of the home, which was built by a company here called Ideal Homes that is big on energy efficiency so they also use those louvered openings above the room doors to try and stabilize temperatures.

The current home doesn't have this so the fan only kicks on when the AC needs to run. My hygrometer is currently reading 52% humidity at 77*F and this feels actually almost chilly. Unfortunately I don't have a humidity % comparison for the old house.

In a way, I'm split. As a lifelong allergy sufferer I prefer it a bit more humid since it keeps my sinuses less congested, but at the same time it is nice that I can save on my electric bill a little by not having the thermostat set cooler.

[Sleuth]

.
There are many upgrades to the thermostat available that will give you more control over the
humidity in your home.

My house was built in 1939, I have the VP IAQ and is very comfortable at 78 - 80* (cooling).
Honeywell VP 8321 or IAQ will have the control feature as will some others. Over heating
with gas furnace will tend to dry out the air in heating season.

Check out Bear's rule and keep your humidity below 55%.
..